The Kynix Blog

CatalogⅠ What Is a Potentiometer?Ⅱ How Does a Potentiometer Work?Ⅲ Types of Potentiometers3.1 Manually adjustable potentiometers3.2 Digital potentiometersⅣ Basic Electrical Characteristics of PotentiometersⅤ Advantages and Disadvantages of Potentiometer5.1 Advantages of Digital Potentiometers5.2 Disadvantages of Digital PotentiometersⅥ Applications of Potentiometer6.1 Audio control6.2 Television6.3 Motion control6.4 Transducers6.5 Computation Ⅶ How to Wire a Potentiometer?7.1 Part 1: Selecting and Preparing a Pot7.2 Part 2: Soldering the Terminals7.3 Part 3: Using Your PotentiometerⅧ Rheostat VS PotentiometerⅨ ConclusionⅩ Frequently Asked Questions about PotentiometerⅠ What Is a Potentiometer?A potentiometer is a three-terminal resistor with a sliding or revolving contact that serves as a voltage divider that may be adjusted. When only one terminal, one end, and the wiper, are employed, it operates as a variable resistor or rheostat. The term "potentiometer" is derived from the phrases Potential Difference and Metering and dates back to the early days of electrical research. It was considered at the time that altering huge wire-wound resistive coils metered or measured a specific amount of potential difference, so making it a type of voltage-metering device. Basic Information of Potentiometer A potentiometer is also known as a pot or potentiometer. The single-turn rotary potentiometer is the most common type of potentiometer. This sort of pot is commonly employed in audio volume control (logarithmic taper) and a variety of other applications. Potentiometers are made from a variety of materials, including carbon composition, cermet, wire-wound, conductive plastic, and metal film. Potentiometers are often used to control electrical devices such as audio volume controls. Potentiometers with a machine can be used as position transducers, such as in a joystick. Potentiometers are rarely used to regulate considerable power (greater than a watt) directly since the power dissipated in the potentiometer is comparable to the power in the controlled load. Ⅱ How Does a Potentiometer Work?How Potentiometer Works A potentiometer is a type of electronic component that is not active. Potentiometers function by changing the location of a sliding contact across a uniform resistance. The full input voltage is applied over the entire length of the resistor in a potentiometer, and the output voltage is the voltage drop between the fixed and sliding contacts, as shown below.  The two terminals of the input source are fixed to the end of the resistor in a potentiometer. To change the output voltage, move the sliding contact along with the resistor on the output side.This differs from a rheostat in that one end is fixed and the sliding terminal is linked to the circuit, as illustrated below.  This is a simple device for comparing the emf of two cells as well as calibrating ammeters, voltmeters, and wattmeters. A potentiometer's basic operation is straightforward. Assume we have two batteries connected in parallel via a galvanometer. As indicated in the picture below, the negative battery terminals are connected together, and the positive battery terminals are likewise connected together via a galvanometer. If the electric potential of both battery cells is the same, there is no circulating current in the circuit, and the galvanometer shows no deflection. The operation of a potentiometer is dependent on this phenomenon. Consider another circuit in which a battery is linked across a resistor using a switch and a rheostat, as shown in the diagram below. Throughout its length, the resistor has the same electrical resistance per unit length. As a result, the voltage drop per unit length of the resistor is constant along its length. Assume that by adjusting the rheostat, we get a volt voltage drop per unit length of the resistor. Now, connect the positive terminal of a standard cell to point A on the resistor, and the negative terminal to a galvanometer. As indicated in the image above, the other end of the galvanometer is in touch with the resistor through a sliding contact. By adjusting this sliding end, a point like B is discovered where there is no current flowing through the galvanometer and thus no deflection in the galvanometer. That is, the voltage appearing in the resistor across points A and B just balances the emf of the standard cell. If the distance between locations A and B is L, then the emf of a standard cell E = Lv volt can be written. This is how a potentiometer monitors the voltage between two locations (in this case, A and B) without introducing any current into the circuit. A potentiometer's specialty is that it can measure voltage with extreme precision. Ⅲ Types of Potentiometers3.1 Manually adjustable potentiometersPotentiometers come in a wide range of shapes and sizes. Manually adjusted potentiometers are classified as having either rotary or linear movement. The available types and their applications are listed in the tables below. In addition to manually adjustable pots, electronically controlled potentiometers, sometimes known as digital potentiometers, are available. Rotary potentiometersThe most common type of potentiometer, with the wiper moving in a circular motion. TypeDescriptionApplicationsSingle-turn potA single rotation of approximately 270 degrees or 3/4 of a full turn.The most common pot is used in applications where a single turn provides enough control resolution.Multi-turn potMultiple rotations (mostly 5, 10, or 20), for increased precision. They are constructed either with a wiper that follows a spiral or helix form or by using a worm gear.Used where high precision and resolution are required. The worm-gear multi-turn pots are often used as trim pots on PCB.Dual-gang potTwo potentiometers combined on the same shaft, enabling the parallel setting of two channels. Most common are single-turn potentiometers with equal resistance and taper. More than two gangs are possible but not very common.Used in for example stereo audio volume control or other applications where 2 channels have to be adjusted in parallel.Concentric potDual potmeter, where the two potentiometers are individually adjusted by means of concentric shafts. Enables the use of two controls on one unit.Often encountered in (older) car radios, where the volume and tone controls are combined.Servo potA motorized potmeter can also be automatically adjusted by a servo motor.Used where manual and automatic adjustment is required. Often seen in audio equipment, where the remote control can turn the volume control knob. Linear potentiometersPotentiometers that allow the wiper to move in a straight line. Also referred to as a slider, slide pot, or fader. TypeDescriptionApplicationsSlide potSingle linear slider potentiometer, for audio applications also known as a fader. High-quality faders are often constructed from conductive plastic.For single-channel control or measurement of distance.Dual-slide potDual slide potentiometer, single slider controlling two potentiometers in parallel.Often used for stereo control in professional audio or other applications where dual parallel channels are controlled.Multi-turn slideConstructed from a spindle that actuates a linear potentiometer wiper. Multiple rotations (mostly 5, 10, or 20), for increased precision.Used where high precision and resolution are required. The multi-turn linear pots are used as trim pots on PCB but are not as common as the worm-gear trimmer potentiometer.Motorized faderFader which can be automatically adjusted by a servo motor.Used where manual and automatic adjustment is required. Common in-studio audio mixers, where the servo faders can be automatically moved to a saved configuration.3.2 Digital potentiometersPotentiometers that be operated electronically are known as digital potentiometers. In most situations, they consist of a sequence of small resistive components. Every resistive element has a switch that can be used as the tap-off point or virtual wiper position. Digital potentiometers can be controlled by up/down signals or protocols such as I2C and SPI. Ⅳ Basic Electrical Characteristics of PotentiometersNominal Total Resistance (Total Resistance)The nominal total resistance is the resistance value that represents the standard value for a potentiometer.Total resistance is defined as the resistance between terminals 1 and 3. Residual ResistanceResidual resistance is the resistance between terminals 1 and 2 when the wiper is positioned at the terminal 1 end or the resistance between terminals 3 and 2 when the wiper is positioned at the terminal 3 ends. The minimum resistance value while the wiper is at its minimum or maximum range of movement is referred to as residual resistance.Residual Resistance Maximum AttenuationWhen the output is at its lowest, the output voltage ratio (in decibels) is the highest. It denotes the extent to which audio equipment's volume can be reduced. Maximum attenuation and insertion loss (see below) are employed instead of residual resistance in the context of potentiometers for volume control. Maximum Attenuation Insertion LossWhen the output is at its maximum, the output voltage ratio (in decibels) is the highest. It denotes the extent to which audio equipment's volume may reach full strength. In the context of volume control potentiometers, insertion loss and maximum attenuation (see below) are employed in place of residual resistance.Insertion Loss Resistance TaperThe proportion of the output voltage between terminals 1 and 2 (or terminals 2 and 3) with respect to the input voltage between terminals 1 and 3. It varies with wiper location, as illustrated by the resistance taper curves on the right. A choice can be made, for example, between the B curve, which is suitable for level adjustment, and the A curve, which produces a more natural sound to the human ear.Resistance Taper Sliding NoiseThis is the minor electrical noise produced when the wiper passes over the resistive element.The more noise there is, the easier it is for audio equipment volume control to produce an unpleasant crackling sound. Sliding Noise Ⅴ Advantages and Disadvantages of Potentiometer5.1 Advantages of Digital PotentiometersDigital potentiometers provide the following advantages: 1)Higher dependability 2)Increased accuracy 3)Small size, several potentiometers can be packed on a single chip4)Minimal resistance drift5)Impervious to environmental conditions such as vibrations, dampness, shocks, and wiper pollution.6)There is no moving part7)Tolerance of up to 1%8)Very low power dissipation, tens of milliwatts or less 5.2 Disadvantages of Digital Potentiometers1)Digital potentiometers have the following drawbacks: they are not ideal for high-temperature environments or high power applications.2)In digital potentiometers, there is a bandwidth consideration due to the parasitic capacitance of the electronic switches. It is the highest frequency at which a signal can traverse the resistance terminals with less than 3 dB attenuation in the wiper. The transfer equation is analogous to that of a low pass filter.3)The wiper resistance's nonlinearity introduces harmonic distortion onto the output signal. The total harmonic distortion, or THD, measures how much the signal degrades after passing through the resistance. Ⅵ Applications of PotentiometerPotentiometers are rarely used to control considerable quantities of power directly (more than a watt or so). They are instead used to change the level of analog signals (for example, volume controls for audio equipment) and as control inputs for electronic circuits. A light dimmer, for example, employs a potentiometer to regulate the switching of a TRIAC, and so indirectly controls the brightness of lamps. Preset potentiometers are commonly used in electronics to make modifications during manufacture or repair. Potentiometers that are operated by the user are commonly employed as user controls and may control a wide range of equipment functions. Potentiometers were widely used in consumer electronics until the 1990s, when rotary incremental encoders, up/down pushbuttons, and other digital controllers took their place. However, they continue to be used in a variety of applications, including volume controls and position sensors. 6.1 Audio controlLow-power potentiometers, both slide, and rotary are used to control audio equipment by adjusting loudness, frequency attenuation, and other audio signal parameters. The 'log pot,' that is, a potentiometer with a resistance, taper, or "curve" (or law) of a logarithmic (log) form, is employed as the volume control in audio power amplifiers, where it is also known as an "audio taper pot," because the amplitude response of the human ear is roughly logarithmic. It guarantees that, for example, on a volume control marked 0 to 10, a setting of 5 sounds half as loud as a setting of 10. An anti-log pot, also known as a reverse audio taper, is simply the inverse of a logarithmic potentiometer. It is nearly always ganged with a logarithmic potentiometer, for example, in audio balance control. Potentiometers work as tone controllers or equalizers when used with filter networks. Because of the straight-line character of the physical sliding action, the term linear is occasionally used incorrectly in audio systems to describe slide potentiometers. When applied to a potentiometer, whether sliding or rotary, the term linear refers to a linear relationship between the pot's position and the measured value of the pot's tap (wiper or electrical output) pin. 6.2 TelevisionPreviously, potentiometers were employed to regulate picture brightness, contrast, and color response. A potentiometer was frequently used to modify "vertical hold," which affected synchronization between the receiver's internal sweep circuit (sometimes a multivibrator) and the received picture signal, as well as audio-video carrier offset, tuning frequency (for push-button sets), and so on. It also aids in wave frequency modulation. 6.3 Motion controlPotentiometers can be employed as position feedback devices in closed-loop control systems, such as servomechanisms. This motion control method is the most basic means of monitoring angle or displacement. 6.4 TransducersPotentiometers are also extensively utilized as a component of displacement transducers due to their ease of manufacturing and ability to produce a large output signal. 6.5 ComputationHigh precision potentiometers are used in analog computers to scale intermediate results by specified constant factors or to create initial conditions for a calculation. A motor-driven potentiometer can be used as a function generator, with a non-linear resistance card providing trigonometric function approximations. For example, the shaft rotation may indicate an angle, and the voltage division ratio could be proportional to the angle's cosine. Ⅶ How to Wire a Potentiometer?Potentiometers, often known as pots, are a type of resistor that is used to control the output signal of an electronic device such as a guitar, amplifier, or speaker. They have a little shaft on top that acts like a knob; when the user twists the shaft, the resistance on the signal increases or decreases. This change in resistance is then utilized to modulate the loudness, gain, or strength of the electrical signal. To install and wire a pot, ground the first terminal, connect the input signal to the third terminal, and then connect the output signal to the terminal in the middle. To accomplish this, solder each wire to the corresponding terminal. Learn How to Wire a Potentiometer 7.1 Part 1: Selecting and Preparing a PotPlace the pot on a flat surface Step 1: Determine the three major terminals that protrude from the pot's center. Place the pot on a flat surface, three prongs facing you. These are your entry points. The first terminal, or terminal 1, is where you'll find your ground. The pot's input signal is sent to the middle terminal, or terminal 2. The output signal is routed to the third terminal, sometimes known as terminal 3. A tiny ring linked to the second terminal is controlled by the top shaft. You may control how low or high the input is by twisting it. If it helps, think of a potentiometer as a dimmer switch. Terminal 1 serves as the ground, terminal 2 serves as the switch, and terminal 3 serves as the switch turned on. In most cases, a potentiometer is used to throttle an input signal so that it can be changed. At times, a pot can be used to overclock a device with a stronger signal. Look at the resistance numbers Step 2: Examine your pot's resistance numbers to see what range you can reach. Pots are rarely used to control signals higher than a few volts, although the resistance they give is substantial. The wider the range, the more control you have over your gadget. The number on the front of the pot represents the highest amount of resistance of the pot. As a result, a 200K pot can give up to 200,000 ohms of resistance. The 100K potentiometer is the most prevalent variety on the market due to its wide range of audio equipment. These numbers are always printed immediately on a pot. They are often located on the other side of the terminals, immediately next to the shaft. Tip: It is critical to understand how much resistance a pot gives in order to assess whether it is suitable for the task at hand. A 2,000-ohm pot will not provide enough range for a sound system, but it will do for a dimmer switch. Three terminals Step 3: Set your pot on a flat surface with the three terminals facing you. Place your pot on a flat area next to your electronic device. Begin with the placement of the pot if you know where you're going to put it. Turn the three terminals so that they are facing you. Remove any panels on your electrical equipment to expose any backside input or output ports. Place the pot on the uppermost set of rows on a breadboard, terminals facing you. Unplug your electronic gadget before opening any panels or soldering any connections. You don't want to be electrocuted or damage your device forever. Cut 0.5–1 in (1.3–2.5 cm) Step 4: Measure and strip any wires you wish to utilize. You can connect the terminals to the device with any type of soldering wire as long as it is not acid-core. If you have an installation location lined up, measure each length of wire from the termination to the device. Using a cutter, cut any wires to expose the copper. Using the notches on the cutter's blades, cut and remove 0.5–1 in (1.3–2.5 cm) of plastic off the tip of each wire. To get a clean strip, set your wire stripper to match the gauge of the wire. Prepare your work surface with a soldering iron and flux, since you will need to solder your wires. Plumbing makes use of acid-core soldering wire. It is incompatible with your electronics. If the soldering wires do not function, they can be used to wire a certain sort of electronic gadget that requires specialist wiring. 7.2 Part 2: Soldering the TerminalsStep 5: Connect a ground wire from terminal 1 on the left to the chassis. Tap a tiny length of wire with your soldering iron and apply flux to the exposed section. Lower the wire and attach it to the exposed metal section on terminal 1 after it has absorbed some flux. Press your soldering tip against the connector to connect the wire to the terminal. Solder the other end of the cable to your electrical device's exposed, unpainted metal surface. You can utilize terminal 3 on the right if you like, but you must turn the knob clockwise to lessen the signal. Connect your device's output circuit to the middle terminal Step 6: Connect your device's output circuit to the middle terminal.Tin another length of wire in the same way and attach it to the center terminal of the pot. Because this is the point at which the signal enters the pot, it must be linked to the device's output. Solder the wire to the metal connection on the rear of your electronic device's output connection. The input of the potentiometer is linked to the center terminal. That is, the signal leaves the electronic, enters terminal 2, and then leaves terminal 3. As a result, terminal 2 must be linked to the port that outputs the original signal from the device. This would require wiring terminal 2 to a guitar's output jack. This would imply connecting terminal 2 to the integrated audio amplifier's speaker output terminal. Terminal 3 Step 7: Connect terminal 3 to the device's input.Terminal 3 is the potentiometer's output. This is where the pot sends data back to the device. Place a length of exposed soldering wire directly on the terminal. After heating the wire with your soldering pen, connect it to the input port of your electronic device. Look for the exposed metal aperture on the back of the knob or the cable connector at the port's back. Solder the wire straight to the pot to connect it. The signal from your pot exits through Terminal 3, thus it must be wired to the spot where you want to deliver the signal. This would imply connecting terminal 3 to the guitar's input jack. The input channels would be linked to Terminal 3 of an audio amplifier. 7.3 Part 3: Using Your PotentiometerMeasure Potentiometer Step 8: Using a voltmeter, check that your pot is operational.Connect the voltmeter terminals to the input and output terminals of the pot. Turn on the voltmeter and turn the dial to feed a signal. Turn the knob on top of your pot to adjust the signal. If the signal reading on the voltmeter changes as you turn the knob, your potentiometer is working. If the voltmeter registers a signal from your pot yet the gadget does not operate when you turn on your electronics, the soldered connections are faulty. Signal From the Pot Step 9: Turn the shaft to adjust the signal on your device.Turn on your gadget and send a signal to the pot by playing music, striking a guitar note, or turning on a light. Twist the shaft to the left to lessen the volume or brightness. Twist the shaft to the right to enhance the volume or brightness of the light. Switch the shaft to the left to turn off the output. Using your pot, you may now control the amount of resistance that your signal receives. Adjust the Amount of Resistance You can add a knob by sliding it over the potentiometer if you like. You can install a potentiometer with the shaft naked and exposed if you wish. If you want to improve the look of your potentiometer, you may always buy a knob. There are several knobs available on the market that are meant to slide over the shaft of a pot and enhance its appearance. That concludes the steps for wiring a potentiometer. Online electronic stores can tell you what possibilities are available for your specific make and model. Ⅷ Rheostat VS PotentiometerDifferences Between Potentiometers and Rheostats A potentiometer controls the voltage. Variable resistance is provided by a rheostat. A potentiometer has three terminals, whereas a rheostat has two terminals. Both gadgets appear to be similar in construction, yet their operating principles are completely different. Two end terminals of the uniform resistance are linked to the source circuit of the potentiometer. Only one terminal of the uniform resistance is connected to the circuit in a rheostat, leaving the other end of the resistance open. A sliding contact on the resistance is included in both potentiometers and rheostats.rheostat The output voltage of a potentiometer is measured between fixed and sliding contacts. Variable resistance is produced in rheostats by alternating between fixed and sliding terminals. The potentiometer's resistance is connected across the circuit. The rheostat's resistance is linked in series with the circuit. The rheostat is commonly used to manage current by altering resistance via a sliding contact. The voltage of a potentiometer is regulated by moving the sliding contact on the resistance. potentiometer To obtain variable resistance, fixed and sliding terminals are employed. The resistance of the potentiometer is connected across the circuit. The resistance of the rheostat is linked in series to the circuit. A rheostat is a device that controls current by adjusting resistance via a sliding contact. A potentiometer's voltage is controlled by changing the sliding contact on the resistance. Ⅸ ConclusionA potentiometer, also known as a variable resistor, is made up of a resistive track with connections at both ends and a third terminal called the wiper, the position of which divides the resistive track. The wiper's position on the track is mechanically modified by spinning a shaft or using a screwdriver. Variable resistors are classified into two operational modes: variable voltage dividers and variable current rheostats. The potentiometer is a three-terminal device that controls the voltage, whereas the rheostat is a two-terminal device that controls current. This is summarized in the table below: TypePotentiometerRheostatNumber of ConnectionsThree TerminalsTwo TerminalsNumber of TurnsSingle and Multi-turnSingle-turn OnlyConnection TypeConnected Parallel with a Voltage SourceConnected in Series with the LoadQuantity ControlledControls VoltageControls CurrentType of Taper LawLinear and LogarithmicLinear Only The potentiometer, trimmer, and rheostat are electromechanical devices with easily adjustable resistance values. They can be single-turn pots, presets, slider pots, or multi-turn trimmers. Wirewound rheostats are primarily used to regulate electrical current. Potentiometers and rheostats are also available in multi-gang configurations and have either a linear or a logarithmic taper. Potentiometers, on the other hand, may provide highly precise sensing and measurement for linear or rotary movement because their output voltage is proportional to the position of the wipers. Potentiometers have many advantages, including inexpensive cost, simple operation, a wide variety of shapes, sizes, and designs, and the ability to be employed in a wide variety of applications. However, as mechanical devices, they have drawbacks such as eventual wear-out of the sliding contact wiper and/or track, limited current handling capabilities (unlike Rheostats), electrical power constraints, and rotational angles limited to fewer than 270 degrees for single turn pots. Ⅹ Frequently Asked Questions about Potentiometer1. What is a potentiometer used for?A position sensor is a potentiometer. They can measure displacement in any direction. Linear potentiometers measure movement linearly, whereas rotary potentiometers measure rotational displacement. 2. What are the 3 terminals on a potentiometer?There are three pins on a potentiometer. Two terminals (blue and green) are linked to a resistive element, and the third (black) is linked to an adjustable wiper. The potentiometer can function as both a rheostat (variable resistor) and a voltage divider. 3. What is a potentiometer also known as?A potentiometer is a three-terminal variable resistor that may be adjusted manually. A potentiometer is often referred to as a potmeter or pot. The single turn rotary potmeter is the most popular type of potmeter. 4. What is the potentiometer principle?The potential lowered across a segment of a wire of uniform cross-section carrying a constant current is precisely proportional to its length, according to the principle of a potentiometer. A potentiometer is a basic device for measuring electrical potentials (or comparing the e.m.f of a cell). 5. Which wire is used in the potentiometer?Potentiometer wire is typically made of alloys such as constantan or manganin. The temperature coefficient of Constantan or Manganin wire is low. 6. Can I use a potentiometer to control AC motor speed?It is unlikely that you will be able to control the speed of an AC fan with a potentiometer. The technology employed determines whether an AC "mains" fan can be speed adjusted with a pot. Typically, a single-phase induction motor with a capacitor start. 7. What is the null point in a potentiometer?The potentiometer's balancing point, also known as the null point, is the point on the sliding wire where the galvanometer indicates zero deflection. The balance point is discovered in order to ascertain the unknown voltage of the cell connected to the cell. 8. What is the sensitivity of the potentiometer?Potentiometer sensitivity is defined as the smallest potential difference detected with a potentiometer. Potentiometer sensitivity can be enhanced by increasing the length of the potentiometer wire. Using a rheostat to reduce the current in the circuit. 9. What is a potentiometer wire?Potentiometer: A potentiometer is a three-terminal resistor with a sliding or revolving contact that forms an adjustable voltage divider. If only one terminal, one end, and the wiper, are employed, it operates as a variable resistor or rheostat. 10. Why copper wire is not suitable for a potentiometer?Copper wire is not suitable for potentiometers due to its high-temperature coefficient of resistance and low resistivity. As a result, even a small change in temperature might cause a significant change in resistance, changing the experimental conditions. 

"What Are the Core Architectural Differences Between HBM3e and HBM4?", "Performance Benchmarks (Speed & Capacity)" -> "How Do HBM3e and HBM4 Compare in Speed and Capacity?"- Missing or improvable schema types detected: Article, FAQPage (JSON-LD missing).- Sections with vague/unsupported claims: "astronomical cost", "improving yield rates" (updated with specific 2026 sold-out supply data and market caps).- Estimated content freshness score: 5/10 (updated to 10/10 for March 2026).-->Executive Summary: The transition from HBM3e to HBM4 in 2026 represents a fundamental architectural shift, doubling the memory interface to 2048-bit and integrating a logic base die to achieve up to 3.3 TB/s bandwidth per stack. While mass production commenced in early 2026, the entire year's supply is already sold out to major hyperscalers, forcing hardware architects to navigate severe allocation constraints and complete interposer redesigns for their next-generation AI accelerators.There is nothing more frustrating for a hardware architect than watching a next-gen GPU idle simply because the memory pipeline can’t keep up. The "Memory Wall" is no longer a theoretical problem; for engineers training trillion-parameter models, it is the daily bottleneck.While HBM3e successfully powered the initial wave of Generative AI, the sheer density requirements of current 2026-era LLMs are hitting the physical limits of 1024-bit interfaces. Enter HBM4—not just a faster iteration, but a fundamental architectural overhaul featuring a massive 2048-bit interface and customizable logic dies.In this guide, we’ll strip away the marketing hype to compare HBM3e vs HBM4 on a silicon level. We will analyze the thermal challenges of 16-hi stacks, the engineering cost of redesigning your interposer, and the practical reality of sourcing these components in a supply chain that is already completely sold out by the giants.What Are the Core Architectural Differences Between HBM3e and HBM4?The core architectural differences between HBM3e and HBM4 center on a doubled 2048-bit interface, the transition of the base die to a 12nm or 5nm logic process, and standardized 16-Hi stack heights. For years, the HBM evolution was linear: slightly faster clocks, slightly taller stacks, but the same fundamental footprint. HBM4 breaks this pattern. It represents a structural fork in the road that forces hardware architects to rethink their silicon interposer designs from the ground up.If you are planning your late-2026 or 2027 tape-out, you need to account for three massive shifts in the spec.1. The Interface Explosion: 1024-bit vs. 2048-bitThe most immediate shock is the bus width: HBM3e operates on a 1024-bit interface per stack, whereas HBM4 doubles this to a 2048-bit interface, as standardized by JEDEC's JESD270-4 specification. Why this matters? It allows HBM4 to achieve higher bandwidth (delivering 2 TB/s to 3.3 TB/s) without aggressively cranking up the voltage, which helps manage power efficiency. However, this creates a routing nightmare for PCB and interposer designers.The Challenge: You cannot simply drop an HBM4 module into an HBM3e slot. The physical pin density requires a much finer pitch on the Silicon Interposer.Actionable Advice: Ensure your packaging partners (like TSMC with CoWoS-L) are validated for the finer bump pitch required by the 2048-bit wide I/O.2. The Base Die: Moving to Logic ProcessesThis is arguably the most exciting feature for AI performance. In HBM3e, the base die (the bottom layer controlling the stack) was built on a legacy memory process. In HBM4, the base die moves to a logic process (typically 12nm or 5nm).This shift transforms the memory stack from a passive data warehouse into an active participant in computation. By integrating logic gates directly into the base die, you can offload specific tasks directly to the memory unit, such as:Error correction and signal conditioning.Specific floating-point operations.Power management behaviors tailored to the host GPU.Internal Linking Context:This is a major departure from standard DRAM Modules, which focus purely on storage density and rely entirely on the CPU/GPU for processing commands. With HBM4, the memory begins to "think."3. Stacking Heights: 12-Hi vs. 16-HiWhile HBM3e pushed the envelope with 12-Hi stacks (12 layers of DRAM), HBM4 normalizes the 16-Hi Stack height. To achieve this without increasing the overall package height (z-height), manufacturers are utilizing Hybrid Bonding technology, which eliminates the solder bumps between layers to reduce thermal resistance and vertical gaps.Fig 1. Cross-section comparison of HBM3e micro-bumps vs. HBM4 hybrid bonding.According to the official specifications released by JEDEC, this vertical scaling allows for capacities up to 64GB per stack, enabling a single GPU to address nearly 400GB of memory—critical for training the trillion-parameter models dominating 2026.How Do HBM3e and HBM4 Compare in Speed and Capacity?HBM4 significantly outperforms HBM3e by offering up to 3.3 TB/s peak bandwidth per stack and up to 64GB capacity, compared to HBM3e's 1.2 TB/s and 36GB limits. When modeling hardware for Next-Gen AI, raw numbers define the feasibility of the architecture. The leap from HBM3e to HBM4 isn't just about faster transfer rates; it’s about breaking the "Bandwidth-per-Watt" barrier that limits current data center efficiency.Below is the comparative breakdown of the specifications defining the 2026 memory landscape:FeatureHBM3e (Current Standard)HBM4 (Next-Gen)Bus Width (Interface)1024-bit2048-bitPin SpeedUp to 9.6 Gbps11.7 Gbps to 13 Gbps Peak Bandwidth per Stack1.2 TB/s2 TB/s to 3.3 TB/s Stack Height8-Hi / 12-Hi12-Hi / 16-HiMax Capacity per Stack24GB / 36GB48GB / 64GB1. Bandwidth: The Impact of the 2048-bit InterfaceWhile HBM3e relies on pushing clock speeds to achieve 1.2 TB/s, HBM4 utilizes its wider 2048-bit memory interface combined with pin speeds up to 13 Gbps to achieve massive throughput (up to 3.3 TB/s). For system architects, this translates to better IOPS per Watt. By running a wider bus, HBM4 reduces the energy cost per bit transferred, addressing the power scaling issues currently plaguing gigawatt-scale data centers.Actionable Advice: When simulating performance for 2026 workloads, adjust your memory bandwidth utilization models. HBM4 allows for greater deterministic latency, meaning you can push utilization closer to the theoretical peak without the jitter often seen in overclocked HBM3e configurations.2. Capacity: Solving the "Parameter Problem"The move to 16-Hi Stacks fundamentally changes the size of the model you can load into VRAM. With HBM4 offering up to 64GB per stack, a standard 8-stack GPU configuration could theoretically hold 512GB of memory.Fig 2. Projected capacity scaling for 8-stack GPU configurations.This allows for training significantly larger parameters without partitioning the model across multiple GPUs, reducing the "communication overhead" that slows down training clusters. As noted in 2026 reports by TrendForce and industry analysts, the demand for HBM4 capacity is driving a massive increase in bit demand, with the global HBM market projected to reach $58 billion this year. Finding the Right Spec for Prototype BuildsWhile HBM4 offers superior specs, availability is the immediate challenge. Many engineers are forced to prototype on high-binned HBM3e while waiting for unallocated HBM4 samples.This is where Kynix’s Electronic Components Sourcing provides a tactical advantage. By utilizing big data to track inventory across over 100 manufacturers, Kynix helps R&D teams identify specific batches of HBM3e that meet the highest performance tolerances (fastest binning), bridging the gap until HBM4 supply stabilizes.How Does HBM4 Handle Thermal Management and Power Efficiency?HBM4 manages thermal output by utilizing Hybrid Bonding to eliminate solder bumps, reducing thermal resistance, and leveraging its wider bus to improve IOPS per Watt despite higher overall stack power. The transition to HBM4 brings an inescapable physics problem: The Thermal Wall. When you increase the stack height from 12 layers (12-Hi) to 16 layers (16-Hi), you are essentially adding four more layers of insulation on top of the logic die, trapping heat in the center of the stack.For hardware engineers, the primary anxiety isn't just peak temperature; it's the thermal variance between the bottom logic die and the top DRAM die. If this delta becomes too high, timing margins degrade, leading to throttling or data corruption.1. Overcoming the Stack Height with Hybrid BondingTo mitigate the heat generated by the denser 16-Hi Stack height, HBM4 largely abandons standard micro-bumps in favor of Hybrid Bonding (Copper-to-Copper bonding).The Old Way (Micro-bumps): In HBM3e, solder bumps connect layers. These bumps create a physical gap (stand-off height) that fills with underfill material, which acts as a thermal insulator.The HBM4 Way (Hybrid Bonding): This technique eliminates the solder bumps, connecting copper directly to copper. This results in zero gap between layers, significantly lowering Thermal resistance and creating a more efficient vertical path for heat to escape to the heat spreader.According to analysis by Semiconductor Engineering, hybrid bonding can improve thermal performance by upwards of 20% compared to traditional micro-bump architectures, a critical margin for maintaining clock speeds under heavy AI training loads.Fig 3. Thermal dissipation efficiency: Standard Bumps vs. Hybrid Bonding.2. Power Efficiency: IOPS per WattWhile the absolute power consumption of an HBM4 module is higher due to its size, its efficiency is superior. The 2048-bit memory interface allows the memory to run at a lower frequency relative to its massive bandwidth output. Lower frequency means lower voltage requirements for the physical layer (PHY), improving the overall IOPS per Watt metric by up to 40% compared to HBM3e. PRO TIP: Managing CoWoS Thermal DesignWhen designing your Silicon Interposer or utilizing CoWoS (Chip-on-Wafer-on-Substrate) packaging for HBM4, do not rely on HBM3e thermal models. The heat flux density of the HBM4 logic die is significantly higher. You must simulate the interaction between the GPU/ASIC hotspot and the HBM4 logic die. Consider using High-K thermal interface materials (TIMs) specifically validated for bumpless stacking to ensure the heat spreader doesn't become the bottleneck.What Are the Integration Challenges and Backward Compatibility of HBM4?HBM4 is not backward compatible with HBM3e; its 2048-bit interface requires a complete redesign of the silicon interposer and host memory controller to handle the increased routing density. If you are hoping for a drop-in replacement where you can simply desolder HBM3e and swap in HBM4, stop now. The transition to HBM4 represents a "hard break" in compatibility.For system architects, this lack of backward compatibility dictates a complete redesign. Here is what you need to prepare for during the migration.1. The Interposer Routing NightmareHBM3e utilizes a 1024-bit interface with specific bump pitches. HBM4 doubles the I/O width. This means the number of traces required on the interposer increases dramatically, requiring finer line/space rules (L/S).The Physical Constraint: Current interposers designed for HBM3e cannot physically route the signal density required by HBM4 without significant crosstalk interference.Actionable Advice: You must engage with your packaging vendor (e.g., TSMC for CoWoS or Intel for EMIB) at the start of the design cycle. You will likely need to move to next-generation interposer technologies that support sub-micron routing features.Fig 4. The density mismatch: Why HBM4 requires a new interposer design.2. Memory Controller & Logic Die SynergyBecause the HBM4 base die is now built on a logic process (12nm/5nm), the host controller on your GPU or ASIC must be updated to take advantage of this. The host needs to be "aware" of the logic die's capabilities to offload specific commands effectively.3. Balancing the BOM: Bleeding Edge vs. Legacy StabilityWhile your core AI accelerator demands the bleeding edge of HBM4, the surrounding subsystems often do not. The cost of redesigning for HBM4 is substantial, so smart engineering involves keeping peripheral systems on mature, cost-effective standards.For auxiliary board functions, control planes, and non-AI processing units, you don't need HBM. In fact, reliable legacy memory like DDR3 memory technology remains a stable, cost-effective choice compared to the volatility of HBM supply. Using these readily available components for "housekeeping" tasks allows you to allocate your high-performance budget where it matters most—the AI interconnect.As noted by market analysts at Yole Group, advanced packaging costs (like those required for HBM4) are projected to account for nearly 40% of the total server bill of materials by 2027, making cost-optimization on non-critical components essential.What Is the Market Availability and Sourcing Strategy for HBM4 in 2026?As of early 2026, HBM4 has entered mass production, but top suppliers have completely sold out their 2026 capacity to major hyperscalers, making strategic sourcing essential. The technical specs of HBM4 are impressive, but they are irrelevant if you cannot buy the chips. As we navigate 2026, the reality of the memory market is defined by one word: Allocation.Major hyperscalers and GPU giants have effectively sold out 100% of the 2026 HBM4 production capacity from SK Hynix, Samsung, and Micron through long-term contracts. For small-to-mid-sized hardware firms, this creates a "supply desert" where obtaining samples for prototyping becomes the biggest risk to your product roadmap.The Reality of HBM4 Mass ProductionWhile JEDEC finalized the JESD270-4 specs in 2025, actual unallocated volume availability lags behind. Although mass production commenced in Q1 2026—with Samsung shipping commercial units in February—widespread availability for new contracts is delayed until 2027. Until then, the market will remain tight, with "spot market" prices likely commanding a premium of 30-50% over contract pricing.According to recent supply chain reports from Reuters, the yield rates for advanced packaging techniques like CoWoS are improving, but capacity remains the primary bottleneck for HBM delivery.Strategies to Survive the ShortageIf you are a procurement manager or lead engineer, you cannot rely on standard distribution channels alone. You need a multi-tiered sourcing strategy:Extend Forecasting Windows: Move from a 12-week forecast to a 52-week rolling forecast. Manufacturers are currently prioritizing clients who provide long-term visibility.Qualify Alternative Bins: Don't lock your design into a single "Golden Sample" speed bin. Validate slightly slower HBM3e bins or alternative density configurations to give your procurement team flexibility when the top-tier stock is unavailable.Leverage the Open Market (Safely): When franchised distributors report "50-week lead times," you must look to independent distributors who hold allocated stock.Fig 5. The anticipated supply gap for Next-Gen Memory.Bridging the Gap with Strategic SourcingThis is where Kynix’s Electronic Components Sourcing becomes a strategic asset. In a market where stock is hidden or fragmented, Kynix leverages big data to monitor global inventory across over 100 manufacturers.Instead of calling vendors one by one, Kynix acts as a force multiplier, helping engineers secure "allocated" HBM3e stock for immediate builds while setting up reliable supply pipelines for HBM4 components as they trickle into the broader market. This data-driven approach minimizes the risk of line-down situations and ensures you aren't left waiting while the giants consume the supply.Making the Right Choice for Your 2026 RoadmapThe leap from HBM3e to HBM4 is one of the most significant architectural shifts in memory history. It is not merely an upgrade; it is a fork in the road. For flagship AI trainers targeting late 2026 and 2027, the 2048-bit interface of HBM4 offers the bandwidth and thermal efficiency required to break the current "Memory Wall." However, this comes at the cost of a complete interposer redesign and the risk of navigating a highly allocated supply chain.For projects requiring immediate time-to-market or cost-efficiency in inference workloads, HBM3e remains the pragmatic, high-performance champion. The "best" memory is ultimately the one you can actually secure for your production line.Don't let supply chain volatility dictate your engineering milestones. Whether you need to secure allocated HBM3e stock for immediate prototyping or plan a resilient procurement strategy for next-gen HBM4 components, verify your supply options with Kynix's Global Sourcing Services today to ensure your hardware is built on time and within budget.Frequently Asked QuestionsIs HBM4 backward compatible with HBM3e?No, HBM4 is not backward compatible with HBM3e. The transition to a 2048-bit interface requires a completely new silicon interposer design and updated memory controllers. Because the physical pin density and routing requirements are vastly different, a direct drop-in replacement is impossible for hardware architects.When will HBM4 be available for mass production?HBM4 entered mass production in early 2026, with Samsung shipping its first commercial units in February. However, because major hyperscalers have completely sold out the 2026 supply through long-term contracts, widespread unallocated market availability for smaller firms is delayed until capacity expansions in 2027.What is the maximum bandwidth of HBM4?HBM4 delivers a massive leap in performance, achieving up to 3.3 terabytes per second (TB/s) of peak bandwidth per stack. By utilizing a wider 2048-bit interface and pin speeds reaching 11.7 to 13 Gbps, it effectively doubles the data throughput compared to previous HBM3e modules.Why does HBM4 use a logic base die?HBM4 shifts the base die to a 12nm or 5nm logic process to transform the memory stack into an active co-processor. 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Introduction A resistor is a passive two-terminal electrical component. After it is connected to the circuit, the resistance is fixed, which can limit the current through the branch connected to it. On one hand, the resistance that cannot be changed is called a fixed resistor, on the other hand, the resistances of potentiometers or variable resistors are changeable. The main physical characteristic of a resistor is to transform electrical energy into thermal energy. It can also be said that it is an energy-consuming element, because internal energy is generated when current passes through it. Figure 1. Use Resistor in Circuit Catalog Introduction Ⅰ Functions of Resistor Ⅱ Three Basic Principles for Resistor Selection Ⅲ The Role of Resistors in Transistor Circuits 3.1 Why Should a Resistor Be Added to the Base of the Transistor? 3.2 Pull-down Resistor in Transistor Circuits Ⅳ FAQ Ⅰ Functions of Resistor In short, the function of resistance is to limit current, divide current, divide voltage, and convert electric energy into internal energy (heating) in the circuit. According to Ohm's law, through calculations, resistors in parallel and series connections can be used to achieve the desired current and voltage. Also there are different resistors and switches combined to produce voice-activated switches, photosensitive switches, infrared switches and so on. How to Use Resistors in circuits? 1) Limit CurrentIn order to prevent the components connected in series from being burnt out by the excessive current and to ensure the normal operation of the electrical appliances, a variable resistor can usually be connected in series in the circuit.2) Current DiversionThe resistor is connected in parallel to the component or circuit that needs to be shunted, and the voltage does not change. The function of this resistor is to divide current.3) Voltage DiversionGenerally, electrical appliances are marked with a rated voltage value. If the power supply is higher than it, the electrical appliance cannot be directly connected to the power supply for a normal operation. In this case, a resistor with suitable resistance can be connected in series in the circuit to share a part of the voltage, therefore the electrical appliance can work at the rated voltage. At this time, the role of the resistor is to divide the voltage.4) Provide Bias VoltageIn the transistor circuit, the resistor is connected between the base of it and the working voltage. At this time, the power supply provides a bias voltage to the base through the resistor, and the resistance can determine the bias voltage. The role of the resistor in the circuit at this time is to provide a bias voltage.5) Negative FeedbackUsed in the resistance between the base and collector of the transistor, then the feedback branch of the negative feedback circuit is formed in the circuit. At this time, the resistor plays a negative feedback role in the circuit.6) OscillationResistor and capacitor form an RC circuit, which can be combined in parallel and in series.7) Damping EffectConnecting a resistor in parallel in the LC resonant circuit can reduce the Q value, at this time, resistor plays a damping effect.8) DecouplingThe use of resistors in multi-stage amplifier circuits can prevent harmful low-frequency interference, which play a decoupling effect.9) Convert Electrical Energy into Internal Energy (Heating)When the current passes through the resistor, it will convert all (or part) of the electrical energy into internal energy, which will generate heat. This principle is often used in electric stoves and heaters in our lives.10) Convert Current into VoltageWhen current flows through the resistor, a voltage will be generated across the resistor. As shown in the figure below, the collector load resistor R2 plays this role, converting the current flowing through the resistor R2 into a voltage and outputting it from U0. Figure 2. Resistor Circuit   Ⅱ Three Basic Principles for Resistor Selection 1) Choose resistors that are manufactured by a certification body that implement high-level standards.2) Choose resistors produced by manufacturers with functional advantages, quality advantages, efficiency advantages, price advantages, and service advantages.3) Choose a manufacturer that can meet the above-mentioned requirements in the model catalog.   Ⅲ The Role of Resistors in Transistor Circuits 3.1 Why Should a Resistor Be Added to the Base of the Transistor? First of all, we must understand the basic principle of the transistor. It is a current-controlled element, which is different from the MOFET, a voltage-controlled element. The transistor has three working areas: cut-off area, amplification area and saturation area. Take NPN transistor as an example, the voltage difference（UBE）of BE is about 0.6V (the actual size depends on the model of the component). When UBE＜0.6V , the transistor is off; when UBE=0.6V, the transistor is in the amplification or saturation region. Figure 3. Schematic Diagram of the NPN Transistor Current When the transistor is in the amplification area, the added resistance between the base and VCC is a bias resistance. The following explains why the base should be added when the transistor is used as a switch. What is the difference between transistor and MOSFET circuits when adding a resistor.The following figure is the most commonly used circuit diagram of NPN transistors. The common input terminal is the I/O port of the microprocessor (microcontroller, DSP, ARM, etc.). Figure 4.  NPN Transistor Take the microcontroller I/O port with 0/5V input as an example. Why must a resistor be connected in series with the base? Can it work without a resistor? Here the resistor is a current control element. When the transistor is in an amplified or saturated state, the voltage of the UBE is 0.6V, and the base current can be calculated according to the input voltage U. The calculation formula is Ib=(U-0.6 )/R1. It can also be seen from the formula that if the current limiting resistor R1 is not connected, when the input voltage is greater than 0.6V, the base current will be very large to burn the tube.Moreover, the resistor cannot be used casually. It needs to be calculated according to the input voltage and the characteristics of the tube. For example, the amplification factor β of the transistor is 50, the maximum current of the collector is 500mA, and the input voltage is 5V. If the design requires the transistor to be in a saturated state, then Ic=500mA, Ib=Ic/β=10M=mA, where the current-limiting resistance R1=(5V-0.6V)/Ib=430Ω. If it is required to input 5V, the collector current is about 200mA, then Ib=Ic/β=200mA/50=4mA can be calculated, finally the current-limiting resistance R1=(5V-0.6V)/Ib=1075Ω (1K can be selected Standard resistance). Note: The above figure is used to explain the example, but it is not very reliable. A more reliable connection method should be to connect a large resistor (such as 10K, or 20K) between the base and the ground. When there is no input, pull the base down quickly to ensure that the tube is in a stable cut-off state.If the NPN transistor in the figure above is replaced with an N-channel MOS tube, the principle is the same. When a high level is input, the tube is turned on, and when a low level is input, the tube is turned off. Figure 5. MOSFET Circuit Since the MOSFET is a voltage-controlled device, the current of the gate (G) is very small and can be ignored, so it can work normally without connecting the resistor R1.The figure after remove the resistor is shown in the below: Figure 6. MOSFET Circuit without Resistor Note: In actual applications, a resistor is generally connected in series to improve reliability. The product reliability is very important. Without current-limiting resistor, when the MOS is   damaged by voltage breakdown, the components on the control terminal will be affected easily, especially the processor, is easily damaged by high current. 3.2 Pull-down Resistor in Transistor Circuits 🔺For TransistorsThe transistor is a current-type driving component, so a current-limiting resistor is connected to the base, generally less than 10K, and the typical values are 3.3K, 4.7K, 5.1K, 6.8K, etc. What is the function of this pull-down resistor?The following figure shows the transistor 8050 switching circuit. The transistor will be turned on when the I/O port outputs a high level, and the transistor will not be turned on. If the I/O port does not output a high level, the base will always be pulled low without a 68K pull-down resistor, that is to say it is in the cut-off state. The circuit may be in an unstable state, especially when it is initialized at the moment of power-on. It is easy to generate noise and easily cause the transistor to malfunction, especially for some general input/output ports. Therefore, this resistor is actually a bias resistor, which makes the base to be pulled down when there is no driving signal, making the circuit more reliable. Figure 7.  Pull-down Resistor in Transistor Circuit Although the pull-down resistor can make the circuit more reliable, tit cannot be too large or too small. If the resistance too large, the base current will not be enough to drive the transistor. On the contrary, if it is too small, the bias voltage will be less than the transistor conduction voltage. In general, this resistance is not more than 100K.Sometimes we see that a capacitor is connected in parallel with this resistor. In fact, this is generally designed in high-speed signal switching circuits. Adding a capacitor can improve performance, as shown below: Figure 8.  RC Circuit 🔺For MOSFETUnlike transistors, MOS transistors are voltage-controlled components, which are driven by voltage. We all know that there is parasitic capacitance between the two pins of MOS transistors. In fact, the key of MOS transistors’ conduction is the charging and discharging of capacitors. Therefore, for the N-type MOS, it will be turned on when Vgs is greater than a certain value, but for the P-type MOS, it will be turned on when the value of Vgs is less than a certain value.Therefore, due to the capacitive effect between the three pins, when the MOS is constantly turned off, the parasitic capacitance voltage can be properly discharged, which is similar to the role of a bleeder resistor and is a kind of protection for the MOS. Figure 9.  MOSFET Circuit Ⅳ FAQ 1. What is the function of the resistor?A resistor has the ability to reduce voltage and current when used in a circuit. The main function of a resistor is to limit current flow. Ohm's law tells us that an increase in a resistors value will see a decrease in current.   2. How do resistors work?A conductor has low resistance, while an insulator has much higher resistance. Devices called resistors let us introduce precisely controlled amounts of resistance into electrical circuits. ... A resistor works by converting electrical energy into heat, which is dissipated into the air.   3. Why do you need resistors?A resistor controls the flow of the electrical current within a circuit. ... Resistors are essential to many electoral circuits, and they can be applied to a myriad of different applications. Protect against voltage spikes. Resistors also protect components against voltage spikes.   4. What role do resistors play in electronic devices?A resistor is a passive two-terminal electrical device that resists the flow of current. It is probably the simplest element in an electronic circuit. It is also one of the most common components as resistance is an inherent element of nearly all electronic circuits. They are usually color-coded.   5. What is a good example of a resistor?A few examples include limiting electric current, voltage division, heat generation, matching and loading circuits, gain control, and setting time constants. They are commercially available with resistance values over a range of more than nine orders of magnitude.   6. What happens if I use a higher ohm resistor?The cases where using a higher value resistor will damage a circuit exist, but are a bit less usual than the cases where it may simply produce a weaker result than desired, or a different frequency response than desired.   7. What is a resistor simple explanation?A resistor is an electrical component that limits or regulates the flow of electrical current in an electronic circuit. Resistors can also be used to provide a specific voltage for an active device such as a transistor. ... The most common type in electronic devices and systems is the carbon-composition resistor.   8. What happens when a resistor blows?Blowing Up a Resistor. By applying too high a voltage to a resistor, the resistor will draw too much current. This causes excessive power to be dissipated in the resistor which makes it go up in flames and a cloud of smoke as this video shows.   9. How is a resistor connected in a circuit?Resistors are said to be connected in “Series”, when they are daisy chained together in a single line. Since all the current flowing through the first resistor has no other way to go it must also pass through the second resistor and the third and so on.   10. Do resistors change voltage?The larger the resistor, the more energy used by that resistor, and the bigger the voltage drop across that resistor. Ohm's Law can be used to verify voltage drop. In a DC circuit, voltage equals current multiplied by resistance. V = I R.

CatalogⅠ IntroductionⅡ DC Power Supply2.1 What is a DC Power Supply?2.2 Types of DC Power Supply2.3 Composition and Operation2.4 Specifications 2.5 Features2.6 Frequently Asked Questions About DC Power SupplyⅢ 5V DC Power Supply3.1 What is the 5V DC Power Supply?3.2 Typical Applications for 5V DC Power Supplies 3.3 Frequently Asked Questions About 5V DC Power SupplyⅣ 12V DC Power Supply4.1 What is the 12V DC power supply?4.2 Typical applications for 12V DC power supplies4.3 Frequently Asked Questions About 12V DC Power SupplyⅤ 24V DC Power Supply5.1 What is the 24V Power Supply? 5.2 What is a 24V Power Supply Used for?5.3 24V Power Supply Requirements & Considerations5.4 What are the Features of a 24V Power Supply?5.5 24V Power Supply Vs. 36V Power Supply5.6 24V Power Supply Problems & Resources5.7 Frequently Asked Questions About 24V DC Power SupplyⅥ Differences Between DC and AC Power Supplies6.1 Characteristics of DC Power Supply6.2 Characteristics of AC power supply6.3 AC Power Supply Vs. DC Power SupplyⅦ How to Choose the Best DC Power SupplyⅠ IntroductionAny electronic system relies on power, and the power supply is what keeps it running. Choosing the correct source can be the difference between a gadget that performs at its best and one that produces inconsistent results. DC to DC converters are available in addition to alternating current (AC) to direct current (DC) power sources. If your system already has DC, a DC to DC converter may be a better design option than the AC mentioned below. There are two types of direct current power supplies: unregulated and regulated. There are various types of regulated supply, including linear, switching, and battery-based. How to Use a Power supplyⅡ DC Power Supply2.1 What is a DC Power Supply?An AC-to-DC converter takes an AC input voltage and converts it to a DC output voltage. The output voltage may contain substantial or negligible quantities of AC frequency components known as ripple voltage, which are connected to the AC input voltage frequency and the power supply's performance, depending on the application requirements. A DC-to-DC converter is a DC power supply that operates on DC input voltage. How to Use a DC Power Supply 2.2 Types of DC Power SupplyThere are mainly four types of DC power supplies: Linear power supply, Switched-mode power supply, Capacitive (transformerless) power supply, Linear regulator. Linear power supplyThe AC input voltage in a linear power supply flows via a power transformer before being rectified and filtered to produce a DC value. Filtering, which can be as simple as a single capacitor or as sophisticated as a pi filter, reduces the amplitude of AC mains frequency present in the rectifier output. The quantity of filtering required by the power supply is determined by the electric load's tolerance for ripple. In other cases, ripple can be completely ignored. In some battery charging applications, for example, the power supply is comprised of a transformer and a diode, with a simple resistor placed at the power supply output to limit the charging current. Figure 1: Simplified block diagram of a programmable linear power supply Switched-mode power supplyThe AC mains input is directly rectified and then filtered to obtain a DC voltage in a switched-mode power supply (SMPS). Electronic switching circuitry switches the resulting DC voltage on and off at a high frequency, producing an AC that passes via a high-frequency transformer or inductor. Switching occurs at a very high frequency (usually 10 kHz — 1 MHz), allowing smaller, lighter, and less expensive transformers and filter capacitors to be used than in linear power supply running at mains frequency. The high-frequency AC is rectified and filtered after the inductor or transformer secondary to create the DC output voltage. The output will be electrically isolated from the mains if the SMPS uses a properly insulated high-frequency transformer; this feature is typically required for safety. Switched-mode power supplies are typically regulated, and a feedback controller monitors the current drawn by the load to keep the output voltage constant. As the power output requirements increase, the switching duty cycle increases. To assist safeguard the device and the user from injury, SMPSs often include safety measures like a current limitation or a crowbar circuit. When a switched-mode supply detects an abnormally high-current power draw, it can presume it's a direct short and shut down before any damage is done. When anomalous supply voltages are present, PC power supplies frequently transmit a power good signal to the motherboard; the absence of this signal prohibits operation. The minimum current output of some SMPSs is set to an absolute maximum. They can only produce electricity above a certain threshold and are unable to function below that threshold. The frequency of the power slicing circuit climbs to a high rate in a no-load condition, leading the isolated transformer to operate as a Tesla coil, causing damage due to the very high voltage power spikes that result. When no load is detected, switched-mode supply with protection circuits may momentarily turn on before shutting off. To allow the supply to run without a primary load, a very modest low-power dummy load, such as a ceramic power resistor or a 10-watt light bulb, can be connected to it. Computer switch-mode power supplies have traditionally had low power factors and have been substantial sources of line interference (due to induced power line harmonics and transients). The input stage of a simple switch-mode power supply can distort the line voltage waveform, causing problems for other loads (and poor power quality for other utility customers), as well as excessive heating in wires and distribution equipment. Customers also pay more for electricity when they use lower power factor loads. Some computer switch-mode power supply conducts power factor adjustment and may use input filters or additional switching stages to prevent line interference to avoid these issues.  Linear DC Power SupplySwitching DC Power SupplySize and WeightLarge transformers are required, which add significant size and weight.If necessary, higher frequencies allow for considerably smaller transformers.EfficiencyTransformer losses are the only important causes of efficiency loss if the system is not regulated. High-power uses, if regulated, will have a significant impact on efficiency.Because they behave like minuscule resistances, transistors have low switching losses. This makes it possible to run high-power applications efficiently.NoiseVoltage ripple can create significant noise in unregulated power supplies, while regulated linear AC DC power systems can have very low noise. They're useful in medical sensing applications because of this.Transistors that switch very quickly produce noise in the circuit. For audio applications, this can be filtered away or the switching frequency can be made exceedingly high, above the limit of human hearing.ComplexityIn comparison to switching DC power supplies, linear DC power supplies feature fewer components and simpler circuits.Because of the additional noise generated by the transformers, massive, complex filters, as well as control and regulation circuitry for the converters, are required. Capacitive (transformerless) power supplyA capacitive power supply (transformerless power supply) reduces the mains voltage to a lower AC voltage by using the reactance of a capacitor. The lowered AC voltage is then typically rectified, filtered, and controlled to produce a steady DC output voltage. The mains voltage is not isolated from the output voltage. As a result, anything connected to the power source must be properly insulated to avoid exposing people and equipment to dangerous high voltage. The voltage reduction capacitor must be able to resist full mains voltage and have sufficient capacitance to handle maximum load current at the rated output voltage. These limits, taken together, limit the practical applicability of this sort of supply to low-power applications. Linear regulatorA linear voltage regulator's job is to convert a fluctuating DC voltage into a fixed, frequently precise, lower DC voltage. They also frequently have a current limiter to safeguard the power source and load from overcurrent (excessive, potentially destructive current). Many power supply applications require a constant output voltage, however the voltage produced by many energy sources varies with changes in load impedance. Furthermore, if the energy source is an unregulated DC power supply, the output voltage will fluctuate with the input voltage. To avoid this, some power supplies use a linear voltage regulator to keep the output voltage constant, regardless of input voltage or load impedance variations. Linear regulators can also lower the magnitude of output voltage ripple and noise. 2.3 Composition and OperationA common DC power supply will be used to demonstrate the general construction of a power supply. As illustrated in the diagram, a basic DC power supply can be constructed using four circuits (or sections), with each block representing a single circuit that performs a certain function. Figure 2: Electrician Training - Integrated Publishing Transformer - The transformer's input is often an AC signal created by a line voltage, such as power from an electric outlet. The primary function of the transformer is to step down (lower the amplitude) or step up (raise the amplitude) the signal to create the necessary DC level at the power supply's output. The transformer can also be used as an isolator. In many applications, it's critical to separate the input AC signal from the device's internal signals. Rectifier - The rectifier receives the signal from the transformer's output. A rectified pulsing DC signal is provided by this device. A half-wave rectifier or a full-wave rectifier can be used. A pulsing DC signal is a voltage or current signal that does not change polarity but has a time-dependent magnitude. Diodes and resistors are commonly used in rectifiers. Filter - A filter is required to transform a pulsing DC signal into a non-pulsating DC signal. In most cases, a simple capacitor filter is sufficient. The filter's output is DC voltage, which typically contains some ripple and slight AC changes. Regulator - The regulator serves two purposes:(1) to smooth the signal from the filter, resulting in a DC signal with no ripples;(2) to maintain a constant voltage at the output.Regardless of changes in the input voltage or the load, the voltage at the regulator's output remains constant (not shown in the diagram). The conversion of a 115 V(RMS) signal to a constant 110 V(DC) voltage is shown in the accompanying image to demonstrate the four steps or blocks required to create a DC voltage from a line voltage. Figure 3: Electrician Training - Integrated Publishing 2.4 SpecificationsMany parameters are required to completely characterize a power supply; nevertheless, there are a set of parameters that are common to most power supply types. Input and output voltages (in volts [V]), output current (in amps [A]), rated output power (in watts [W]), input signal frequency (in Hertz [Hz], kilohertz [kHz], or megahertz [MHz]), and regulation are all examples. Input voltageis the magnitude and type of the voltage applied to the power supply.Input frequencyis the frequency of the input signal.Output voltageis the magnitude of the DC voltage at the output of the device.Output currentis the current associated with the output voltage.Output poweris the power (in watts) delivered to the load.Regulationindicates the stability of the output voltage.Line regulationis the maximum steady-state amount that the output voltage changes as a result of a specified change in input line voltage.Load regulation is the maximum steady-state amount that the output voltage changes as a result of a specified change in load. Mounting requirements are less important, but they should be considered if the power supply is to be appropriately fitted to the application or system. There are several mounting solutions available, including: Board mountCircuit mountWall mountDIN rail mountRack mountDesktop 2.5 FeaturesDC power supplies have extra features like circuit protection and cooling, which might be useful in certain situations. DC power supply' performance and/or physical integrity can be influenced by several factors. Normally, circuits that protect the power supplies are built into the device's design and construction. Here are a few examples: Short circuit protectionOverload protectionOver current protectionOver voltage protectionUnder voltage protectionOver temperature protection Several cooling methods are used to protect DC power supplies: Fan coolingHeat sink coolingWater cooling DC power supplies can also incorporate a number of other features: Battery backupHot swappablePower factor correctionTemperature compensationWeatherproof 2.6 Frequently Asked Questions About DC Power Supply1.What are DC power supplies used for?The main job of an AC/DC power supply is to transform the alternating current (AC) into a stable direct current (DC) voltage, which can then be used to power different electrical devices. Alternating current is used to transport electric power all across the electric grid, from generators to end users. 2.Why is a DC power supply needed?A DC power supply is used by engineers to test a component, circuit or electronic device, such as IoT devices, medical products, mobile phones, and remote industrial sensors. The DC power supply allows engineers to set and supply specific voltages to power the device to confirm it’s working as intended. 3.What is the difference between AC and DC power supply?In direct current (DC), the electric charge (current) only flows in one direction. Electric charge in alternating current (AC), on the other hand, changes direction periodically. 4.How do you use a DC power supply?A DC power supply is easy to use. These instruments connect to a device that’s being tested via leads that are inserted into the DC power supply panel. Using the front panel display, engineers can set voltages or current levels to power the device for testing. 5.How does a DC power supply work?A DC power supply works by providing a regulated direct current to power a component, module, or device. Most DC power supplies have two modes of operation. In Constant Voltage (CV) mode, the power supply controls the output voltage based on the user settings. In Constant Current (CC) mode, the power supply regulates the current. 6.What type of power supply reduces the mains voltage to a lower AC voltage?linear voltage regulator 7.What do linear voltage regulators often have to protect the power source and load from overcurrent?current limiter 8.What do many power supply applications require?constant output voltage 9.What happens when the output voltage fluctuates with the input voltage?if the energy source is an unregulated DC power supply 10.What do some power supplies use to keep the output voltage constant?a linear voltage regulator 11.What can lower the magnitude of output voltage ripple and noise?Linear regulators 12.How can a basic DC power supply be constructed?four circuits (or sections) Ⅲ 5V DC Power Supply3.1 What is the 5V DC Power Supply?One of the most prevalent power sources in use today is the 5V power supply (sometimes known as a 5V DC power supply). Using a mixture of transformers, diodes, and transistors, a 5V DC output can be generated from a 50V AC or 240V AC input. There are two types of 5V power supplies: regulated 5V power supplies and unregulated 5V power supplies. Switching regulated AC to DC, Linear regulated AC to DC, and Switching regulated DC to DC are the three types of 5V regulated power supply. 5V DC power supply Switching regulated 5V DC power supplies, also known as SMPS power supplies, switchers, or switched-mode power supplies, use a complicated high-frequency switching technology that includes pulse width modulation and feedback to regulate the 5V DC output voltage. To reduce common and differential mode noise conveyed to the line and load, switching regulated power supply uses significant EMI filtering and shielding. Our 5V DC switchers come with galvanic isolation as standard, giving our customers input to output and output to ground isolation for optimum versatility. Switching regulated power supplies are very efficient, tiny, and light, and come in AC-DC single and wide-adjust output, as well as DC-DC, variants. Our Low Profile broad adjust output switchers are externally programmed and can be voltage or current regulated. A dissipative regulating circuit regulates the output of linear regulated 5V DC power sources. They are exceedingly stable, have very minimal ripple, and do not create EMI due to switching frequencies. Our 5V DC linears come with galvanic isolation as standard, giving our customers input to output and output to ground isolation for optimum flexibility. AC to DC single and broad adjust output linear regulated power supplies are provided. Basic power sources with an AC input and an unregulated 5V DC output are known as unregulated 5V DC power supplies. The output voltage is affected by the input voltage as well as the load. These power supplies are both affordable and dependable. 3.2 Typical Applications for 5V DC Power Supplies Industrial automationTTL circuit powerPrecision control circuitsResearch projects 3.3 Frequently Asked Questions About 5V DC Power Supply1.What does 5V DC mean?DC 5V/2A, means that the input voltage, to recharge the battery is 5 volts of direct current. It has two outputs, one 2.1A USB (for tablets and Raspberry Pi and high-current devices, the other 1A USB for phones and smaller devices. 2.Can I use a 12V power supply on a 5V device?The device will very likely burn out. In addition, depending on what the device is and the capacity of the 12V supply, connecting a 12V supply to a device rated 5V max could lead to a hazard - fire, explosion, etc. Mostly it will get damaged. 3.What is the difference between 5V and 12V?The main disadvantage of the 5V system is that voltage drop is a more significant limiting factor. However 5V systems are much more power efficient than 12V systems; a 5V linear system will always be 2.4 times more efficient than it's equivalent 12V system. Ⅳ 12V DC Power Supply4.1 What is the 12V DC power supply?One of the most prevalent power sources in use today is 12V power supplies (or 12V DC power supplies). A combination of transformers, diodes, and transistors is used to generate a 12V DC output from a 120V AC or 240V AC input. There are two types of 12V power supplies: 12V regulated power supplies and 12V unregulated power supplies. Switching regulated AC to DC. Linear regulated AC to DC, and Switching regulated DC to DC are the three types of 12V regulated power supply. How does a modern Power Supply work? Switching regulated 12V DC power supplies, also known as SMPS power supplies, switchers, or switched-mode power supplies, use a complicated high-frequency switching technology that includes pulse width modulation and feedback to regulate the 12V DC output voltage. To reduce common and differential mode noise conveyed to the line and load, switching regulated power supply uses significant EMI filtering and shielding. Our 12V DC switchers come with galvanic isolation as standard, giving our customers  input to output and output to ground isolation for optimum versatility. Switching regulated power supplies are very efficient, tiny, and light, and come in  AC-DC single and wide-adjust output, as well as DC-DC variants. Our Low Profile broad adjust output switchers are externally programmed and can be voltage or current-regulated. A dissipative regulating circuit regulates the output of linear regulated 12V DC power sources. They are exceedingly stable, have very minimal ripple, and do not create EMI due to switching frequencies. Our 12V DC linears come with galvanic isolation as standard, giving our customers input to output and output to ground isolation for optimum flexibility. AC to DC single and broad adjust output linear regulated power supplies are provided. Basic power sources with an AC input and an unregulated 12V DC output are known as uncontrolled 12V DC power supplies. The output voltage is affected by the input voltage as well as the load. These power supplies are both affordable and dependable. 4.2 Typical applications for 12V DC power suppliesComputer Peripherals and Networking ApplicationsTelecommunications and Fiber optic NetworkVoice, Data and Analog CommunicationsUniversities and Educational FacilitiesInstrumentation and ElectronicsUtility and Power IndustriesData AcquisitionMedicalMilitaryMotor control 4.3 Frequently Asked Questions About 12V DC Power Supply1.How do you make a 12V DC power supply?Things that you will need to make this power supply is:Piece of veroboardFour 1N4001 diodesLM7812 regulatorTransformer that has an output of 14v - 35v AC with an output current between 100mA to 1A, depending how much power you will need. (I found a 16v 200mA transformer in a broken alarm clock.)1000uF - 4700uF capacitor1uF capacitorTwo 100nF capacitorsJumper wires (I used some plain wire as jumper wires)Heatsink (optional) 2.Is 12V AC the same as 12V DC?12V DC is safer than 12V AC. Body resistance decreased when the 12V AC still may cause the dead, 12V DC will not be in 100%. However, the hazard degree of electric shock to the human body mainly depends on the size of the current passing through the human body and the length of the energization time. 3.What is DC 12V input?12V power supply is one of the most common power supplies in use at present. In general, a 12V DC output is obtained from a 100VAC-277VAC input using a combination of transformers,12V power supplies can be of two types: 12V constant power supplies, and 12V unconstant power supplies. 4.Can I use a 9V power supply on a 12V?It depends on whether your power supply is regulated. If you need regulated (stable) 12V, and the 9V supply is unregulated, it could give you up to 14V or slightly higher when not loaded. 5.Can I use a 12V power supply on a 15V?Assuming the polarity is correct, plugging in a 12V input to a device requiring 15V won't do any damage, however if you undervolt an amplifier, you may get clipping or other distortion. 6.How do you convert 12V DC to 6V DC?It's possible to step 12 volts down to 6 volts by incorporating a pair of 10,000-ohm resistors into the circuit. Cut two lengths of wire, and strip each wire of 1/2 inch of insulation at each end. Attach one end of the first wire to the positive terminal on the power supply. 7.Can I use a 19V power supply on a 12V?Any device that was designed to run at 12V is likely to be fried by 19V. It might catch fire, even though it's not very likely. You must have an equal or higher current rating in order to use an AC adapter. Ⅴ 24V DC Power Supply5.1 What is the 24V Power Supply?A power supply with a voltage of 24 volts can convert AC to DC. The voltage level can be modified at the same time as the AC power is converted to DC power. Some gadgets require DC, although they only have access to AC from the wall. This adjustment is simple to do using the 24V power supply. A DC power supply is an economical and effective alternative in locations where AC power is not available. How to Make 24 Volt Power Supply 5.2 What is a 24V Power Supply Used for?A power supply with a voltage of 24 volts can be utilized in a variety of applications. The 24V supply could be a useful solution whenever an object requires power. Although we usually think of a 24V Power Supply as being utilized on a building site or in the workplace, it has a variety of additional uses. A 24V power source is required in many audio and lighting scenarios. In addition, medical and communication difficulties may necessitate the usage of a 24V power supply. Power supplies are usually compact and can be a relatively portable solution to a problem. The 24V power supply has a wide range of applications. 5.3 24V Power Supply Requirements & ConsiderationsThere are various factors to consider while selecting a 24V Power Supply. Check to see if the device you need to power is compatible with the power supply you buy. Input Voltage & Output VoltageThe output range of a power supply will vary substantially depending on the input voltage. You'll need to make sure you get a 24V power supply with the right voltage range. The longer the range, the more expensive the device will be in general. Power RatingWatts will be used to determine the power rating. Some of the smaller units will have an output of around 80 watts, while the larger ones will be closer to 1000 watts. Keep in mind that certain 24V Power Supplies are designed for light-duty industrial use, while others are designed for heavy-duty industrial use. Make sure you get a power source that meets your requirements. 5.4 What are the Features of a 24V Power Supply?To get the most out of your equipment purchase, it's critical to grasp the features of a 24V power supply. The many output ports and the consistent power supply are three things to be aware of. The 24V power supply's combination of qualities is what makes it so beneficial to its users. Multiple Output PortsThe majority of the 24V power supply includes many outputs. In most cases, one output is insufficient to complete the task. Consider setting up audio equipment with the 24V power supply. One output, without a doubt, will not suffice. The majority of 24V power supplies will offer two or three options. When there are many output ports, you should be able to specify voltage restrictions and even timings to help you regulate whatever is attached to the output ports. Overall, if you're going to buy a 24V power supply, you should go for one that has numerous output ports. ProgrammableMany of the 24V power sources on the market today can be programmed. This implies you can use them with a computer system for product setup and testing. This is critical for medical applications as well as light and audio. With higher-end equipment, the programmability of the 24V power supply will become more sophisticated. Some of the basic programmability is simple enough for a layperson to understand. Constant Voltage Power SupplyA 24V power supply can be mounted to provide backup power to a region that isn't getting enough power. On your power supply, you can choose the required voltage and maximum current for the load. The 24V power supply is an excellent choice in circumstances where steady power is required. Many users consider these to be extremely valuable and dependable pieces of gear. 5.5 24V Power Supply Vs. 36V Power SupplyWhen picking a power source for your project, a higher voltage is usually the better option. The higher voltage can do more and create better outcomes, but your system must be able to manage the additional voltage. When electricity is not restricted, the difference in these additional 12 volts of power might cause damage. Before determining that more is better, make sure that everything will function together well. 5.6 24V Power Supply Problems & ResourcesDamage occurs, but it is frequently repairable. People's largest problem with power supplies is that they aren't installed and put together correctly. You must comprehend what the 24V power source, ground, output, and other components entail. Make sure the process is set up appropriately, and you should have fewer issues with this resource in the long run. If you're having trouble with a 24V power supply, electricians and programmers are usually well-versed on how to get the most out of one. 5.7 Frequently Asked Questions About 24V DC Power Supply1.Can I use a 12V power supply on a 24V?Going the other way - 24V LED strips on a 12V power supplyIf you're trying to go the other way and connect a 12V power supply to operate 24V LED strips, unfortunately, you are out of luck. You'll need to purchase a transformer or voltage booster, or, more straightforwardly, a 24V power supply. 2.Can I use 24V AC for 24V DC?24 volt AC/DC converters with 19 to 28V AC input. These are also known as 24 volt rectifiers, and voltage regulators. They can be used whenever 24V AC power is available and 24V DC power is needed, up to 60 watts. 3.Can I use a 19V power supply on a 24V?As long as the adapter can supply as much or more than the device needs, you're good. Attaching an adapter to a device that needs more current than it can supply will likely damage the adapter. Ⅵ Differences Between DC and AC Power Supplies6.1 Characteristics of DC Power SupplyThe advantages and disadvantages of direct current, in which electricity always flows in the same direction, are as follows. The direction of the current in alternating current is constantly changing. As a result, when a capacitor or inductor is used in the circuit, the current flowing to the load is delayed or advanced in proportion to the voltage behavior. The voltage and direction of the current are always constant with direct current, therefore the behavior of the capacitors and coils is also consistent. As a result, there is no advance or delay in the circuit in DC. Because the direction of the current is shifted in alternating current (AC), not all of the electricity travels through the load, and some power is generated simply passing back and forth between the load and the power source. This is referred to as reactive power. Because the current runs in a consistent direction, all electricity goes through the load in direct current. A scallop is being pushed out in this photograph. As a result, no reactive power is generated, allowing power to be used more efficiently. Another benefit of direct current is that it may be stored in batteries, capacitors, and other devices. Direct current, on the other hand, has several drawbacks. One of them is that interrupting the current is difficult. Because the direct current is always subjected to a constant voltage, particularly when the voltage is high, problems such as arcs (sparks) may arise at the point of interruption, or there may be a risk of electric shock in the immediate vicinity. When the voltage changes from positive to negative or negative to positive in alternating current, the voltage drops to zero for a brief duration. You can interrupt the current more safely than with a direct current if you aim for a time when the voltage is low. In addition, while converting DC voltage, it must first be converted to AC and then back to DC. As a result, DC voltage conversion equipment is larger and more expensive than AC voltage conversion equipment. The severe corrosion of subterranean pipes and insulators necessary for electricity transmission is another downside of direct current. Because DC continually flows in the same direction, electrostatic induction and electrical corrosion cause power transmission equipment to corrode. Direct current is what comes out of batteries, capacitors, and other stored objects. As a result, battery-powered products are compatible with direct current. The power supply in an average home, on the other hand, is AC, while DC is used in electronic equipment like computers and home appliances like televisions. The AC from the outlet is converted to DC using capacitors and other devices to power such devices. However, in data centers where DC is primarily used, the installation of a DC power supply is encouraged to minimize the loss caused by the conversion of AC to DC. 6.2 Characteristics of AC power supplyDirect current is what comes out of batteries, capacitors, and other stored objects. As a result, battery-powered products are compatible with direct current. The power supply in an average home, on the other hand, is AC, while DC is used in electronic equipment like computers and home appliances like televisions. The AC from the outlet is converted to DC using capacitors and other devices to power such devices. However, in data centers where DC is primarily used, the installation of a DC power supply is encouraged to minimize the loss caused by the conversion of AC to DC. For example, if you need 3000W (watts) of power, you'll need 30A (amperes) of current if the voltage is 100V, but only 3A if the voltage is 1000V. In other words, if the voltage is increased by a factor of 10, the current is lowered to 1/10, and the power loss is reduced to 1/100, or the square of 1/10. As a result, for long-distance transmission, extremely high voltages are utilized. Of course, the current-voltage is unsuitable for usage in houses and workplaces. For major factories, the voltage is 100,000 volts, for buildings, it is 6600 volts, and for houses and offices, it is 200 volts or 100 volts. As a result, the voltage of electricity transmitted from a power plant must be reduced to suit the region or location. In comparison to direct current, alternating current can be easily changed by transformers, making it more appropriate for power distribution as infrastructure. Another benefit of AC is that it is simple to shut off while electricity is being delivered, as the voltage lowers to zero at regular intervals. It can also be used like a domestic power supply (outlet) without discriminating between positive and negative, making device connection and operation easier. Because the voltage value is constantly changing and there are periods when the voltage dips to zero, AC requires a higher voltage than the target voltage for the required amount of heat. AC voltage has a sinusoidal waveform with a maximum voltage of 2 times the running value. The effective value must be exceeded by the insulation performance and equipment standards. Another feature of AC is that coils and capacitors have a significant impact on it. Coils and capacitors provide voltages that induce current to flow in the opposite direction of the current flow, causing the current to advance or lag in the circuit. Alternating current electricity is created and sent to a power plant. Three AC waves are sent out at the same time at a power plant, with the waveform of the AC altered by 120 degrees. A three-phase alternating current is a name for this sort of power. There are two types of air conditioners: single-phase and three-phase. A three-phase AC is utilized for high-voltage power transmission in particular. It is converted to one phase, along with the voltage conversion, when it is supplied to a residential outlet. AC is used in standard power outlets and for motors that do not require precise control, such as vacuum cleaners and ventilation fans. Motors for air conditioners, washing machines, refrigerators, and other appliances, on the other hand, do not use AC power as is, but instead need inverters for fine control. 6.3 AC Power Supply Vs. DC Power Supply Alternating Current Direct CurrentAmount of energy that can be carriedIt's safe to transport over greater distances in the city and can deliver more power.DC voltage can only travel so far before it starts to lose energy.Cause of the direction of flow of electronsRotating magnet along the wire.Steady magnetism along the wire.FrequencyDepending on the country, the frequency of alternating current is 50Hz or 60Hz.The frequency of direct current is zero.DirectionWhile passing through a circuit, it reverses its direction.It flows in one direction in the circuit.CurrentIt is the current of magnitude varying with timeIt is the current of constant magnitude.Flow of ElectronsElectrons alternate between forward and backward motion.Electrons move steadily in one direction or 'forward'.Obtained fromA.C Generator and mains.Cell or Battery.Passive ParametersImpedance.Resistance onlyPower FactorLies between 0 & 1.it is always 1.TypesSinusoidal, Trapezoidal, Triangular, Square.Pure and pulsating. Ⅶ How to Choose the Best DC Power SupplyThe most common selection criteria are:Number of output channels (single or multi output)Output voltage, current, and powerSetting resolution and accuracyRipple and noiseFeatures and programmabilityAdvanced features like current measurement with nanoamp resolution, sequencing, analog inputs, digital I/O, and  programming features 

  A printed circuit board, also known as PCB, is the electrical connection provider of electronic components. It has been developed for more than 100 years; its key point is about layout design. The main advantage of using circuit board is to greatly reduce wiring and assembly errors, improve the level of automation and productivity.   In today's blog, we are going to introduce PCB systematically to show you what is PCB, what's its features, and its manufacturing method and wiring technique and so many more.     Catalog   PCB Introduction PCB Form PCB Features PCB Advantages PCB Basic Manufacturing How to Designing Your Own PCBs PCB Function Testing PCB Design PCB Wiring How Does PCB Works PCB Recycle FAQ PCB Introduction   A printed circuit board, also known as PCB, is the electrical connection provider of electronic components. It has been developed for more than 100 years; its key point is about layout design. The main advantage of using circuit board is to greatly reduce wiring and assembly errors, improve the level of automation and productivity.   Since printed circuit boards are not general end products, there is a slight confusion in the definition of it. For example, the motherboard for personal computers is called the motherboard and cannot be called the circuit board directly, although there is a circuit board in the motherboard. They are not the same, so the relationship between the two cannot be said to be the same when evaluating the industry.   Another example: because integrated circuit parts are mounted on a circuit board, the news media call it IC board, but in essence, it is not equal to a printed circuit board. We commonly refer to PCB as a bare board which components are not on it.   The number of PCB layers can be divided into a single panel, double panel, four-layer board, six-layer board and multilayer board.   PCB Material Common materials of PCB boards are electric boards, glass fiberboards, and various types of plastic boards. PCB manufacturers generally use an insulating portion consists of glass fibre, non-fabric, and resin, then pressed with epoxy resin and copper foil to form a prepreg.   PCB Metallic Coating The metal coating is where the substrate line meets the electronic component. Furthermore, metal solderability, contact, resistance, and so on will have a direct impact on the component's effectiveness. And different metals have a direct impact on production costs.   Copper, tin (the thickness is usually 5 to 15 m), lead-tin alloy (or tin-copper alloy, that is solder, the thickness is 5 to 25 m, about 63 percent is tin), gold (usually plated on the interface), and silver are the most commonly used metallic coatings (usually plated on the interface, or as a whole is silver alloy).   PCB Line Design Software Simple layout design can be completed by hand, but complex circuit design is usually realized through computer-aided design (CAD), and well-known design software includes CAD, Pads (that is PowerPCB), Altium designer (that is Protel), FreePCB, CAM350, and others.   PCB Form   The current circuit boards are primarily made up of the following components:   The Line and Pattern: A line is a tool used to connect the original parts. The large copper surface will be designed as the grounding and power supply layer in the design. The wiring route is created concurrently with the pattern.   Dielectric is used to keep lines and layers insulated.   Through-hole / via: it can switch the lines above the two layers on and off, larger ones are used to set components, and non-through holes (nPTH) are typically used as surface mounting positioning and fixing screws for assembly.   Solder resistant / Solder Mask: not all copper surfaces needed solder parts with sin, so the non-tin soldering area will print something to separate tin (usually epoxy resin), to avoid a short circuit. According to different processes, this can be divided into green oil, red oil and blue oil to distinguish different functional areas.   Legend / Marking/ Silk screen: it is not necessary. Its main function is to mark the name and position of each part on the circuit board for easy maintenance and identification after assembly.   Surface Finish: because the copper surface is easy to oxidize in the general environment, leading to failure to solder tin ( or solder poor), therefore, it will make the copper surface protection which needing to solder sin. The methods of protection include HASL, ENIG, Immersion Silver, tin, Immersion Tin, and OSP, which are generally called surface treatment, having their own advantages and disadvantages.   PCB Features   Bare panels (no parts on them) are also known as "Printed Wiring Board (PWB)". The board itself is made of insulating, non-bending material. The thin wire material that can be seen on the surface is copper foil, which is originally covered on the whole board but is etched away in the manufacturing process, and the remaining part becomes a small net line. These lines are called conductor pattern or wiring and are used to provide electrical connections to parts on the PCB.   The colour of PCB is usually green or brown, which is the colour of the solder mask. It is an insulating protective layer that protects copper wire, prevents short circuit caused by wave welding, and saves solder consumption. Also, a silkscreen will be printed on the solder mask layer. Text and symbols (most are white) are usually printed on them to indicate the location of each part on the board. Silkscreen is also called a legend.   Integrated circuits, transistors, diodes, passive components (such as resistors, capacitors, connectors, etc.) and a variety of other electronic components are installed when the final product made. By connecting wires, electronic signals can be connected and their functions can be work.   PCB Advantages   (1) Because of the reproducibility and consistency of the graphics, the errors in wiring and assembly are reduced, and the maintenance, debugging and checking the time of the equipment are saved;   (2) The design can be standardized and interchangeable;   (3) High density of wiring, small size, lightweight, which is beneficial to the miniaturization of electronic equipment;   (4) It is beneficial to mechanization and automatic production, increasing labour productivity and reducing the cost of electronic equipment     PCB Basic Manufacturing   PCB manufacturing methods are classified into two types: subtractive and additive. At the moment, the subtractive etching copper foil method is primarily used in mass industrial production.   Basic Manufacturing Procedure: First, we’ll need a blank circuit board (a circuit board with complete metal foil), and the rest are required circuit boards.   Screen printing: a screen mask is made from a pre-designed circuit diagram. The screen's unnecessary circuit is covered with wax or waterproof material. Following that, the screen mask is placed on a blank circuit board, with a protective agent applied to the screen to prevent corrosion. Finally, immerse the circuit board in the corrosion solution; the part not covered by the protective agent will be corroded away, leaving only the rest to be cleaned away.   Photosensitive board: a pre-designed circuit diagram is printed on a transparent film mask (the simplest method is to print the film with a printer), and the required part is printed in an opaque color in the same way. Then, apply photosensitive pigment to the blank circuit board, place the prepared film mask on the board while it is blazing for a few minutes, remove the mask, and use a developer to display the pattern on the board.   Engraving: use a milling machine or laser engraving machine to remove unnecessary parts of a blank line directly.   Other Manufacture Procedure:   （1）Additive The additive, is a pre-coated copper substrate coated with a photoresistor (D/F), exposed to ultraviolet light and exposed where it is needed. Then using electroplating to thicken the copper of the formal circuit line to the required specification, and plating a layer of anti-corrosion thin tin, and finally remove the photoresist (this process is called film removal), and then etch the copper foil layer under the photoresist.   （2）Layer Method The lamination method is one of the methods of making multilayer printed circuit board. The outer layer is made after the inner layer is wrapped, and the outer layer is treated by the subtractive or additive method. The sequential layer method can be used to get the multi-layer printed circuit board with multiple layers by repeating the action of the stacking method. 1. Making inner layer 2. Laminated formation( bonding different layers) 3. Layer completion ( Outer metal-containing foil film by subtractive method, mixing with the additive method) 4. Drilling   （3）Panel Method 1. Whole PCB electroplating 2. Add a barrier layer where the surface is to be retained 3. Etching4. Removal of barrier layer   （4）Pattern Method 1. Add a barrier layer to the area where the surface is not required 2. Electroplating requires with thickness 3. Removal of barrier layer4. Etching into unnecessary foil film to disappear   （5）Complete Addition Method 1. Add a barrier layer where there is no conductor 2. Circuit consisting of no electrolytic copper   （6）Partial Addition Method 1. Covered with electrolytic copper PCB 2. Add a barrier layer where there is no conductor 3. Electrolytic copper plating 4. Removal of barrier layer 5. No electrolytic copper disappeared until etched under the original barrier layer.   （7）ALIVH ALIVH (Any Layer Interstitial Via Hole，Any Layer IVA), this is using aramid fiber fabric as the substrate. 1. Prepreg: dip the fabric in an epoxy resin to form a “Adhesive sheet”. 2. Laser drilling. 3. Filling the hole with conductive paste. 4. Attaching copper foil to the outer layer. 5. Making Circuit pattern by etching on copper foi. 6. Gluing the copper foil on the semi-finished product after the second step. 7. Laminated formation 8. Repeating steps 5 to 7 until completed.   （8）B2it (Buried Bump Interconnection Technology) 1. First make a double panel or multilayer board. 2. Printing silver paste as cone on copper foil. 3. To place the adhesive on a silver paste, making silver cone to penetrate the adhesive. 4. Attaching the previous adhesive to the board of the first step. 5. Etching the copper foil of the adhesive into a circuit pattern. 6. Repeat the second to fourth steps until it completed.   How to Designing Your Own PCBs   How do you go about designing your own PCB? The ins and outs of PCB design are way too in-depth to get into here, but if you really want to get started, here are some pointers:   1. Find a CAD package: there are a lot of low-cost or free options out there on the market for PCB design. Things to consider when choosing a package:   Community support: are there a lot of people using the package? The more people using it, the more likely you are to find ready-made libraries with the parts you need.   Ease-of-use: if it's painful to use it, you won't.   Capability: some programs place limitations on your design- number of layers, number of components, size of the board, etc. Most of them allow you to pay for a license to upgrade their capability.   Portability: some free programs do not allow you to export or convert your designs, locking you into one supplier only. Maybe that’s a fair price to pay for convenience and price, maybe not.   2. Look at other people’s layouts to see what they have done. Open Source Hardware makes this easier than ever.   3. More practice.   4. Maintain low expectations. Your first board design will have lots of problems. Your 20th board design will have fewer, but will still have some. You’ll never get rid of them all.   5. Schematics are important. Trying to design a board without a good schematic in place first is an exercise in futility.   Finally, a few words on the utility of designing your own circuit boards. If you plan on making more than one or two of a given project, the payback on designing a board is pretty good- point-to-point wiring circuits on a protoboard is a hassle, and they tend to be less robust than purpose-designed boards.   PCB Function Testing   More intensive PCB, with the higher bus speed and analog RF circuits, pose unprecedented challenges to the testing, where efficient testing requires careful design, thoughtful testing methods and appropriate tools which can provide credible test results.   In high-density UUT, if calibration or diagnosis is required, manual work is likely to be required. This is because the machine is limited and the test requires faster (the UUT can collect data quickly with a probe instead of feedback the information to the edge connector), in this case, that the operator is required to probe the test points on the UUT to make sure the test points are clearly marked.   Testing Issues include: （1） Is the probe bigger than the test point? （2）Is the probe in danger of shorting several test points and damaging UUT? （3） Is there a shock hazard to the operator? （4）Can each operator find out the test point quickly and check it out? （5）Are test points large and easy to identify? （6）How long does it take the operator to press the probe on the test point to get an accurate reading? （7）If the time is too long, there will be some trouble in the small test area, for example, the operator's hand will slide, so it is recommended to expand the test area to avoid this problem.   After considering the above problems, the test engineer should re-evaluate the type of the test probe, modify the test file to better identify the location of the test point or even change the requirements for the operator.   PCB Automatic Exploration In some cases, the use of automated probes may be required, such as when PCB is difficult to detect manually, or when the test speed is significantly reduced due to the technical limitations of the operator, under this case which an automated approach should be considered.   The automatic probe can eliminate human error, reduce the possibility of short circuit at several test points, and speed up test operation. However, it should be noted that there may be some limitations to automated probes, depending on the vendor's design, including:   （1）A size of UUT （2）Number of synchronous probes （3）How close are the two test points? （4）Positioning accuracy of the testing probe （5）Can the system detect UUT on both sides? （6）How fast does the probe move to the next test point? （7）What is the actual interval required for the probe system? (it is generally larger than an offline functional test system.)   Automatic detection usually does not touch test points with probe and is generally slower than the production line, so two steps may be required: if the detector is used only for diagnosis, the traditional function test system can be used in the production line, and the detector should be put on the side of the production line as the diagnostic system. If the purpose of the detector is using the UUT to calibrate, it is necessary to use multiple systems, which is still much faster than manual operation.   Another key issue is how to integrate the test system into the production line. Is there still room on the production line? Can the system be connected to the conveyor belt? Fortunately, many new detection systems are compatible with the SMEMA standard, so they work in an online environment.   PCB Boundary Scan Because it requires specialized components to perform the task, this technology should have been discussed prior to the product design phase. Devices with IEEE1194 (boundary-scan) support can be purchased in UUT with a digital circuit, allowing most diagnostic problems to be solved with little or no detection. However, because it expands the area of each compatible device, boundary scanning reduces the overall functionality of the UUT (4 to 5 pins per chip and some wires).   When selecting this technology, the goal is to improve diagnosis. Furthermore, it is emphasized that boundary scans can be used to program Flash memory and PLD devices on UUT, which strengthens the case for selecting the test method.     PCB Design In the design of a printed circuit board, the layout of components and wiring of circuit connection are two key aspects.   PCB Layout The layout is to put the circuit device in the printed circuit board wiring area.   The layout not only affects the wiring work behind it, but it also has a significant impact on the overall performance of the circuit board. To meet the requirements of process, detection, and maintenance, the components should be uniform, neat, and compactly placed on the PCB to minimize the lead and connection between the components, resulting in uniform assembly density.   PCB Functional Differentiation Components should be arranged in groups based on their power-supply voltage, digital and analog circuits, speed, current, and so on, to avoid interference with one another.   When installing the digital circuit and analog circuit on the circuit board, the ground wire and power supply system of the two circuits should be completely separated, and the digital circuit and analog circuit should be arranged in different layers if the conditions allow. When arranging the fast, medium, and low-speed logic circuits on the circuit board, they should be close to the connector, while the memory should be far away from the connector.   This reduces common impedance coupling, radiation, and crosstalk. The clock and high-frequency circuits, which are the primary sources of disturbance emitter, must be arranged separately and away from the sensitive circuit.   PCB Thermal Magnetic Balance The heating parts and the heat-sensitive parts are as far away as possible, the influence of electromagnetic compatibility should be considered.   Manufacturability: (1) Surface The mounting parts are installed on one side as far as possible and simplify the assembly process.   (2) Spacing The minimum distance between components is determined according to the shape of components and other related properties. At present, the distance between components is generally not less than 0.2mm~0.3mm, the distance between components and PCB edge should be more than 2mm.   (3) Direction The direction and density of the elements should be favourable to the convection of the air. Considering the assembly process, the component direction is as consistent as possible.   PCB Wiring   1. Wires (1) Width The minimum width of the printed wire is determined by the adhesive strength between the conductor and the insulating substrate and the current value flowing through them. Printed wire can be as wide as possible, especially power lines and ground wires, as wide as possible under the condition of the plate surface, even if the area is tight, generally not less than 1mm.   In particular, ground wires, even if they are not allowed to be widened locally, it is necessary to widen somewhere permitted to reduce the resistance of the whole ground wire system. For example, the conductors longer than 80mm, even if the current is small, should be widened to reduce the influence of conductor voltage drop on the circuit.   (2) Length To minimize the length of the wiring, the shorter the wiring, the less interference and crosstalk, and the lower the parasitic reactance and the less radiation. Especially the FET gate, transistor base and high-frequency circuit should pay more attention to short wiring.   (3) Gap The distance between adjacent conductors should meet electrical safety standards. The main electrical issues affecting wiring spacing are crosstalk and voltage breakdown. The spacing should be as wide as possible for ease of operation and production, and the minimum spacing should be appropriate to the applied voltage. This voltage includes the operating voltage, the additional fluctuation voltage, the overvoltage, and the peak voltage for other reasons. For safety reasons, the spacing should be wider when there is a current-voltage in the circuit.   (4) Path The signal path from driver to load should be constant in width. The path impedance (resistance, inductance, and capacitance) changes as the path width changes, resulting in reflection and line impedance imbalance. As a result, it is best to keep the path width constant.   Furthermore, it is best to avoid right and sharp angles for the wiring corner, which should generally be greater than 90 °. The inner edge of the right path can generate a concentrated electric field, which produces noise coupled to the adjacent path, and the 45 °path outperforms the right angle and acute angle paths. When two conductors come together at an acute angle, the acute angle should be turned into a circle.   2. Aperture and Pad  The aperture of components should be better matched with the diameter of the lead; in other words, the diameter of the installation hole should be slightly larger 0.150.3mm than the component's lead diameter. DIL packaging pins and most small components have an aperture of 0.8mm and a pad diameter of about 2mm.   For large pad aperture, in order to get better adhesion ability, the ratio of the aperture and the diameter of the pad is about 2 for epoxy glass plate and 2.5~3 for phenol cardboard.   Perforation, which is commonly used in multilayer PCBs, has a minimum available diameter that is related to plate thickness, and the plate thickness to aperture ratio is usually 6:1. A high-speed signal generates 14nH inductance and 0.38pF capacitance when perforated. As a result, when laying high-speed signal channels, the number of holes should be kept to a bare minimum.   If layer changes are unavoidable for high-speed parallel lines (such as address and data lines), it is necessary to ensure that the number of holes in each signal line is the same, and that the number of holes is minimized. When necessary, a printed conductor protection ring or protective line should be installed to prevent oscillations and improve circuit performance.   3. Grounding Design Unreasonable grounding design will affect the printed circuit board, fail to reach the design target, and even can not work. The ground wire is the reference of the potential in the circuit and the common current channel. The ground potential value is zero theoretically, but in fact, because of the existence of conductor impedance, the potential everywhere of the ground wire is not all zero. As long as the ground wire has a certain length, it's potential may not in zero everywhere. The ground wire is not only a necessary common circuit channel, it also a channel for interference.   One point grounding is the basic principle of eliminating grounding interference. The ground wire of all circuits and devices must be connected to a unified grounding point, which is used as the circuit and the zero potential reference point of the equipment. One point grounding is divided into common ground wire series grounding and independent wires parallel grounding.   The common ground-wire series grounding is simple. The grounding lead of each circuit is relatively short, and its resistance is relatively small. This kind of grounding method is often used in the earthing of the equipment cabinet. The independent wires parallel grounding has one ground point which is defined as the ground reference point. The other points that need to be grounded are directly connected to this point, and the earth potential of each circuit is related only to the ground current base impedance of the circuit, which will not be affected by other circuits.   The Following Points Should Be Noted in Specific Wiring: （1）The line length is as short as possible in order to minimize the lead inductance. In low-frequency circuits, multipoint grounding is avoided because the ground current of all circuits flows through a common grounding impedance or grounding plane.   （2）Common ground wires should be arranged as far as possible on the edge of the printed circuit board. As much copper foil as possible should be retained on the circuit board as the ground wire, which can enhance shielding ability.   （3）The double-layer plate can use the ground surface, the purpose of which is to provide a low-impedance ground wire.   （4）In a multi-layer printed circuit board, a grounding layer can be set, and it is designed as a mesh. The spacing of the earth grid can not be too large because one of the main functions of the earth wire is to provide the signal return path. If the spacing of the grid is large signal-loop area will be formed, which will cause radiation and sensitivity problems. In addition, if the signal reflux path is a small loop area, other ground lines will not take into effect.   （5）The earth surface can minimize the radiation loop.   How Does PCB Works PCB Recycle   PCB manufacturing technology is a very complex, comprehensive processing technology. Especially in the process of wet processing, a large amount of water is needed, so there are many kinds of heavy metal wastewater and organic wastewater discharged.    The composition is complex, and the treatment is difficult. If the copper foil utilization ratio of the printed circuit board is 30% and 40%, most of the copper content is in wastewater. If the thickness of each copper foil is 35 microns based on 10, 000 square meters of double panels, the wastewater contains about 4500 kilograms of copper, and there are many other heavy metals and precious metals. These are found in waste liquid and wastewater, if the metal is discharged without treatment, it is not only a big waste but also pollutes the environment.    Therefore, the treatment of wastewater and the recycling of copper and other metals in the process of PCB production are of great significance and are indispensable parts in PCB production.   It is well known that the wastewater in the production of the printed circuit board is a large amount of copper, and a very small amount of lead, tin, gold, silver, fluorine, ammonia, organic compounds and organic complexes, etc.   As for the production of copper wastewater, the main processes are: copper sink, copper plating, copper electroplating, etching and various PCB pretreatment processes (chemical pretreatment, brush plate pretreatment, pozzolanic ash grinding plate pretreatment, etc.).   The copper-containing wastewater produced by the above processes can be divided into complex wastewater and non-complex wastewater according to its composition. In order to make the wastewater treatment meet the environment-protection standard, and the maximum allowable compound concentration of copper is 1mg/l (according to copper), but different wastewater treatment methods must be adopted for different copper-containing wastewater. FAQ   1. What is PCB? A printed circuit board, or PCB, is used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate.   2. What is PCB and types of PCB? A printed circuit board (PCB) is a thin board made from fiberglass, composite epoxy, or other laminate materials. PCBs are found in various electrical and electronic components such as beepers, radios, radars, computer systems, etc. Different types of PCBs are used based on the applications.   3. What can a PCB be used for? Printed circuit boards (PCBs) are used to mechanically support and electrically connect electronic components using conductive pathways, tracks or signal traces etched from copper sheets laminated onto a non-conductive substrate, employed in the manufacturing of business machines and computers, as well as communication ...   4. Why are PCB green? It is due to the solder mask, which protects the copper circuits printed on the fibre glass core to prevent short circuits, soldering errors, etc. ... The colour of the solder mask gives the board its appearance.   5. What is PCB and its advantages? Compact Size and Saving of Wire. A characteristic PCB includes a large number of electronic components. On a Printed circuit board, the interconnection between the components is made through copper tracks instead of using a number of current carrying wires. It makes the interconnections less bulky.   6. How long does it take for PCBs to break down? 3.5 to 83 days. The time it takes for half of the amount of PCBs (initially) present to be broken down ranges from 3.5 to 83 days for molecules with 1 to 5 chlorine atoms. In water, PCBs are essentially broken down by the effect of sunlight (photolysis).   7. What is the disadvantage of PCB? Disadvantages: Easy to Cause Handling Damage. Process Uses a Carcinogen (Thiourea) Exposed Tin on Final Assembly can Corrode.   8. Which PCB design software is the best for beginners? Top Best PCB Design Software of 2021 a. PROTEL (Altium Designer)  b.PADS (PowerPCB)  c. ORCAD.  d. Allegro.  e. Eagle（Easily Applicable Graphical Layout Editor） f. Kicad. g. EasyEda. h. Fritzing.   9. What are the advantage of flexible PCB? The flexible circuit board are designed for saving room and improving the flexibility to meet a smaller and higher density mounting design, it also helps to reduce the assembly process and enhance reliability.   10. Why do we use PCB instead of breadboard circuit? The advantages of a printed circuit board: the board is permanent to have an electronic device worked. PCB has a better current carrying capacity comparing to a breadboard, you can make your traces wider to take more current so that work well. ... You can mount heat-sinks to the board so that have them rigid.

Executive Summary: Transistors in 2026The semiconductor transistor remains the fundamental building block of modern electronics. As of January 2026, the industry has shifted toward Gate-All-Around (GAAFET) architectures at the 2nm process node, enabling AI chips like NVIDIA's Blackwell B200 to pack over 208 billion transistors. This guide updates legacy concepts with 2026 standards, covering operation modes, NPN/PNP switching circuits, and the latest market statistics approaching a $1 Trillion valuation.What is a Semiconductor Transistor in 2026?A semiconductor transistor is an active semiconductor device used to amplify, control, and generate electrical signals and power. It functions as a variable current switch capable of controlling output current based on input voltage. Unlike ordinary mechanical switches (such as relays), transistors use electrical signals to control their own opening and closing, allowing for switching speeds in the gigahertz (GHz) range—critical for modern 5G and AI applications.Key 2026 Insight: While traditional Bipolar Junction Transistors (BJTs) are still used in analog circuits, modern high-speed computing relies on GAAFET (Gate-All-Around Field Effect Transistor) technology, which has replaced FinFET at the 3nm and 2nm nodes to minimize power leakage.Video: Transistors Basics Explained Ⅰ How do Electrons and Holes Function in a Transistor?The transistor is a current-controlled device (BJT) or voltage-controlled device (FET) that facilitates signal amplification, oscillation, and modulation. Its operation relies on the movement of charge carriers: electrons (negative charge) and holes (positive charge carriers).A standard BJT has three terminals (Emitter, Base, Collector), three regions, and two PN junctions. Understanding the internal structure is key to grasping how 2026 hardware manages billions of switching operations per second.Figure 1. Transistor Structure (NPN Configuration)Movement of Charge Carriers:Figure 2. Movement of Charge CarriersHoles vs. Electrons: The hollow circles in Figure 2 represent positively charged holes, while solid dots are negatively charged electrons. "Hole movement" is effectively the macroscopic result of electrons filling vacancies.Emitter (E): Heavily doped to emit a large number of electrons. When forward-biased, it injects carriers into the base.Base (B): Very thin and lightly doped. In an NPN transistor, the P-type base allows most electrons from the emitter to diffuse directly to the collector, with very few recombining with holes (creating the small base current, IB).Collector (C): Large surface area designed to collect electrons drifting through the base. It dissipates the most heat, especially in power transistors used in 2026 EV inverters.Current Equation: IE (Emitter Current) = IC (Collector Current) + IB (Base Current).Ⅱ What are the Key Characteristics of Transistors?Transistors define the logic of all digital circuits. Their behavior is governed by the following core principles:1) Current Control (BJT): The small base current (IB) controls the large collector current (IC).NPN Current Direction: Base → Emitter.PNP Current Direction: Emitter → Base.2) Amplification Factor (β): Transistors amplify signals by a factor of β (Beta). If IB = 1mA and β = 100, then IC = 100mA. This principle amplifies weak sensor signals in IoT devices.3) Saturation (Switch ON): When IB is sufficient (e.g., ≥1mA for small signal transistors), the voltage drop Vce ≈ 0.3V. The transistor acts as a closed switch.4) Cutoff (Switch OFF): When Vbe < 0.7V (for Silicon), the transistor is fully off. Vce is high (equal to supply voltage), acting as an open switch.Design Tip for 2026: For NPN switching circuits, connect the load to the Collector and the Emitter to Ground (GND). For PNP, connect the Emitter to Power (VCC) and the load to the Collector. NPN is generally preferred in modern logic due to higher electron mobility compared to hole mobility. Ⅲ What are the Three Operational Regions of a Transistor?To effectively use a transistor in AI hardware or power regulators, one must understand its three operational states: Cut-off, Active, and Saturation.Figure 3. Transistor Circuit And Operational Regions(1) Cut-off Region (Digital "0"): The transistor is OFF. Ube < Threshold (0.7V). IB = 0, IC ≈ 0. The switch is open.(2) Active Region (Amplification): Used for analog signal processing (audio, radio). The Emitter junction is forward-biased, and the Collector junction is reverse-biased. IC = β * IB.(3) Saturation Region (Digital "1"): The transistor is fully ON. Both junctions are forward-biased. IC cannot increase further even if IB increases. Uce is minimal (~0.2V).In embedded systems and logic gates (like those in the newest 2nm chips), transistors toggle rapidly between Cut-off and Saturation, avoiding the Active region to minimize power loss.Figure 4. Voltage CharacteristicⅣ How to Analyze Input and Output Characteristics?4.1 Input CharacteristicsThe input characteristic curve relates the base current (IB) to the base-emitter voltage (VBE). It resembles the curve of a standard diode.Figure 5. Input CharacteristicWhen VCE increases, the collector's ability to "sweep" electrons improves, slightly reducing the recombination in the base. This shifts the curve to the right, meaning less IB flows for the same VBE.4.2 Output CharacteristicsThe output characteristic relates the collector current (IC) to the collector-emitter voltage (VCE) for various fixed values of IB.Figure 6. Output CharacteristicUnderstanding the Graph: The horizontal axis is VCE. The initial steep rise is the Saturation Region (switch closed). The flat horizontal lines represent the Active/Amplification Region, where IC is constant regardless of VCE (acting as a constant current source controlled by IB). Ⅴ What Causes Saturation and Cutoff Distortion?Signal distortion occurs when a transistor amplifier is improperly biased, causing the output waveform to be "clipped" at the top or bottom.5.1 Waveform Analysis of Basic Common Emitter Amplifier CircuitFigure 7. Waveform Analysis of Common-emitter Amplifier CircuitSaturation Distortion (Bottom Clipping): Occurs when the static operating point (Q-point) is too high. IB is too large, causing UCE to drop near 0V during the positive half-cycle of the input.Cutoff Distortion (Top Clipping): Occurs when the Q-point is too low. IB is too small, causing the transistor to turn OFF during the negative half-cycle of the input.5.2 Why use Transistors as Switches?Feasibility: The distinct "ON" (Saturation) and "OFF" (Cutoff) states allow transistors to replace mechanical switches. Modern SiC (Silicon Carbide) transistors can switch high voltages in EVs with minimal efficiency loss.Necessity: Microcontrollers (CPUs/MCUs) operate at low voltages (3.3V or 5V) and cannot directly drive high-power loads like motors or LED arrays. A transistor acts as the bridge, allowing a weak software signal to control massive power. Ⅵ How to Design Transistor Switching Circuits?6.1 Basic Switching Circuit of NPN TransistorsFigure 8. NPN Transistor Switch CircuitLow-Side Switching: In an NPN circuit, the Load (R1) is connected between VCC and the Collector. The Emitter connects to Ground. When the Base receives a High signal (e.g., 3.3V from a GPIO pin), current flows from C to E, turning the load ON.6.2 Basic Switching Circuit of PNP TransistorsFigure 9. Basic Switching Circuit of PNP TransistorHigh-Side Switching: Common PNP models like the 8550 are used here. The Emitter connects to VCC. The Load connects between the Collector and Ground. Logic: A LOW signal (0V) at the Base turns the PNP transistor ON. A HIGH signal turns it OFF. This is often used for driving buzzers or indicators where the ground path must remain common. Ⅶ Frequently Asked Questions About Transistors (2026 Update)1. How does a semiconductor transistor work?A transistor works by using a small control current at the Base (or voltage at the Gate) to regulate a much larger current flowing between the Collector and Emitter (or Source and Drain). This allows it to act as an amplifier or a high-speed electronic switch.2. How is a transistor used as a switch?The transistor operates as a solid-state switch by toggling between the Cutoff region (Open circuit, OFF) and the Saturation region (Short circuit, ON). It eliminates moving parts, allowing for billions of operations per second in modern CPUs.3. What is the PN junction of a transistor?A BJT contains two PN junctions. The Emitter-Base junction is forward-biased to inject carriers, while the Collector-Base junction is typically reverse-biased to collect them. These junctions form the potential barriers that control current flow.4. How many PN junctions are there in a transistor?2 PN JunctionsA Bipolar Junction Transistor (BJT) has two PN junctions (Base-Emitter and Base-Collector). Field Effect Transistors (FETs) rely on channel conductivity rather than junction injection.5. What are the two basic types of transistors?The two primary categories are Bipolar Junction Transistors (BJT) (current-controlled) and Field Effect Transistors (FET) (voltage-controlled). As of 2026, FETs (specifically MOSFETs and GAAFETs) dominate digital electronics.6. What are the terminals of a transistor called?For BJTs: Emitter, Base, and Collector. For FETs/MOSFETs: Source, Gate, and Drain.7. What is the difference between NPN and PNP?An NPN transistor turns ON with a positive current to the Base (High-Side control usually requires voltage > Emitter). A PNP transistor turns ON when the Base is pulled Low (voltage < Emitter). NPN is more common in switching applications due to better electron mobility.8. What is the most popular transistor in 2026?The MOSFET remains the most widely used transistor globally, accounting for 99.9% of all transistors. However, for cutting-edge AI chips (like NVIDIA Blackwell), GAAFET (Gate-All-Around) is the new standard, while SiC and GaN dominate power electronics in electric vehicles.{ "@context": "https://schema.org", "@type": "Article", "headline": "What is a Semiconductor Transistor? 2026 Comprehensive Guide", "datePublished": "2019-01-01", "dateModified": "2026-01-05", "description": "A deep dive into semiconductor transistors, covering electrons/holes, NPN/PNP characteristics, and 2026 industry standards like GAAFET and AI chip architectures.", "author": { "@type": "Organization", "name": "Kynix Semiconductor" }, "mainEntity": { "@type": "FAQPage", "mainEntity": [ { "@type": "Question", "name": "How does a semiconductor transistor work?", "acceptedAnswer": { "@type": "Answer", "text": "A transistor works by using a small control current at the Base (or voltage at the Gate) to regulate a much larger current flowing between the Collector and Emitter, effectively acting as an amplifier or switch." } }, { "@type": "Question", "name": "What are the two basic types of transistors?", "acceptedAnswer": { "@type": "Answer", "text": "The two main types are Bipolar Junction Transistors (BJT) and Field Effect Transistors (FET). 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