ti Related Articles

Ⅰ IntroductionThe potentiometer is a fundamental component that remains essential in 2025's electronics landscape.Widely used in circuits to control volume in audio equipment, adjust lighting brightness (dimmers), and calibrate sensors in IoT devices, potentiometers bridge the gap between user input and digital or analog response.While the working principle might seem complex at first, understanding the internal construction simplifies the concept. Whether you are working with classic analog circuits or interfacing with modern microcontrollers like Arduino or ESP32, mastering the potentiometer is a key skill. Figure 1: Standard Rotary PotentiometerⅡ Potentiometer Related Video Introduction Video: How A Potentiometer Works & Options for Wiring Potentiometer Video Description: This video explains the internal mechanics of a potentiometer and demonstrates common wiring configurations, including volume control (voltage divider), variable resistor, and signal blender setups. Ⅲ Potentiometer Basics3.1 Potentiometer SymbolTwo primary symbols represent potentiometers. The American standard (ANSI) depicts a zigzag line with three terminals, while the international standard (IEC) uses a rectangular box with three terminals. Both symbols indicate a fixed resistive track with a third terminal (the wiper) connecting to the center.  Figure 2: ANSI vs. IEC Potentiometer Symbols 3.2 Potentiometer Pin ConfigurationPin No.Pin NameDescription1Fixed EndConnected to one end of the resistive track (often Ground in volume circuits).2Variable End (Wiper)The wiper terminal that moves along the track to provide variable voltage or resistance.3Fixed EndConnected to the other end of the resistive track (often Input or VCC). 3.3 FeaturesTechnical specifications vary by model, but standard rotary potentiometers generally feature:Type: Rotary (Panel Mount or PCB Mount)Standard Resistance Values: 1K, 5K, 10K, 50K, 100K, 500K, 1M Ohm.Power Rating: Typically 0.25W to 0.5W for carbon film; higher for wirewound.Maximum Input Voltage: Often rated up to 200V DC (check datasheet).Rotational Life: Standard carbon pots offer ~10,000 to 15,000 cycles. High-end conductive plastic models can exceed 1-2 million cycles. 3.4 Selecting a PotentiometerPotentiometers (POTs) are essentially variable resistors. They adjust voltage or signal levels via a mechanical knob. Selection depends on two main criteria: Resistance (R-ohms) and Power (P-Watts).The resistance value determines the load placed on the source circuit. Common values include 10K and 100K for audio and signal processing. High-impedance circuits often require 500K or 1M pots.The power rating indicates how much heat the component can dissipate. Standard potentiometers are rated around 0.3W to 0.5W, making them suitable for low-current control signals, but not for directly driving high-power motors or heavy loads. 3.5 How to Use a Potentiometer?While standard resistors have two terminals, a potentiometer has three. The diagram below illustrates the internal function. Figure 3: Internal Structure of a Potentiometer The resistive track between terminals 1 and 3 provides a constant resistance (e.g., 10kΩ). The wiper (terminal 2) moves along this track, tapping into the voltage at a specific point.For example, with a 10k linear potentiometer:Resistance between Pin 1 and Pin 3 is always 10kΩ.If the wiper is set to the exact center (50%), the resistance between Pin 1 and Pin 2 is 5kΩ, and Pin 2 to Pin 3 is also 5kΩ.This "Voltage Divider" principle is what makes potentiometers effective for reading analog signals into microcontrollers like an Arduino. 3.6 ApplicationsAudio Control: Volume and tone knobs in guitars and amplifiers.Position Sensing: Joysticks in gaming controllers and servo motors in robotics.User Interface: Control dials for dimmers, fan speeds, and temperature settings.Calibration: Trimmer potentiometers (trimpots) are used on PCBs to fine-tune circuit performance. 3.7 2D Diagram (Model P232)Figure 4: Mechanical Dimensions (Model P232)  Ⅳ How to Wire a Potentiometer?Wiring a potentiometer is straightforward, but correctness depends on the application (Volume vs. Variable Resistor). The most common configuration is the Voltage Divider (Volume Control), where you ground the first terminal, input signal to the third, and take the output from the middle wiper. 4.1 Part 1: Selecting and Preparing a Pot Step 1: Identify Terminals. Place the pot on a flat surface with the shaft pointing up and terminals facing you. Terminal 1 (Left): Typically Ground. Terminal 2 (Middle): Output (Wiper). Terminal 3 (Right): Input (VCC/Signal). Step 2: Check Specifications. Locate the markings on the case. "100K" indicates a maximum resistance of 100,000 ohms. Verify the taper code (e.g., 'B' often usually Linear, 'A' usually Audio/Logarithmic in modern Asian/American components).Tip: Choose resistance based on your circuit. A 10K pot is standard for microcontroller inputs (5V logic), while audio circuits often use 100K or 250K/500K for guitars. Step 3: Preparation. Ensure your electronic device is unplugged to prevent short circuits. If prototyping, insert the pot into a breadboard. If soldering to a panel, ensure the surface is clean.Step 4: Wire Prep. Measure and cut your wires. Strip approximately 0.5 inches (1.3 cm) of insulation from the ends. Use standard rosin-core solder for electronics; avoid acid-core solder (used for plumbing) as it damages circuit boards. 4.2 Part 2: Soldering Your TerminalsStep 5: Ground Connection. Solder a wire from Terminal 1 (Left) to the Ground (GND) point on your device or chassis. This sets the "zero" point for the volume/voltage. Step 6: Signal Output (Wiper). Connect a wire to Terminal 2 (Middle). This is your modified signal. If connecting to a microcontroller (like Arduino), this wire goes to an Analog Input (e.g., A0). If using it for audio, this goes to the amplifier input. Step 7: Signal Input. Connect Terminal 3 (Right) to your signal source or voltage supply (e.g., 5V or Audio Source). This allows the current to flow across the resistive track to the ground. 4.3 Part 3: Using Your PotentiometerStep 8: Testing. Before powering up, you can use a multimeter set to Resistance (Ohms). Measure across Pins 1 and 2. Turning the knob should smoothly change the resistance value. Step 9: Operation. Power on your device. Turning the knob clockwise should increase the signal (volume/voltage), and counter-clockwise should decrease it.Finishing Touches: You can add a knob cap for better ergonomics and aesthetics. Ensure the pot is securely mounted to prevent the wires from twisting during operation. Ⅴ FAQ1. What are the main types of potentiometers?Potentiometers are classified by their construction and movement:Rotary Potentiometers: The most common type, controlled by turning a knob.Linear (Slide) Potentiometers: Controlled by sliding a fader, common in audio mixers.Digital Potentiometers (DigiPots): Controlled electronically via protocols like I2C or SPI, used in modern digital circuits.Membrane Potentiometers: Flat, flexible sensors used in touch interfaces. 2. How do you read potentiometer taper markings (A vs. B)?The "Taper" indicates how resistance changes as you turn the knob. Modern Standard (Asia/USA/IEC): A = Audio (Logarithmic) Taper: Resistance changes slowly at first, then quickly. Best for volume controls because human hearing is logarithmic. B = Linear Taper: Resistance changes evenly. Best for adjusting brightness, fan speed, or sensor calibration.Note: Vintage European devices sometimes used the reverse (A=Linear, B=Log), but modern components almost universally follow A=Log, B=Linear. 3. What does "10k potentiometer" mean?This designation refers to the total resistance of the component. If you measure the resistance between the two outer terminals (Pin 1 and Pin 3), it will always read 10kΩ (10,000 ohms), regardless of the knob's position. The wiper allows you to select a value between 0Ω and 10kΩ. 4. When should I use a low vs. high resistance potentiometer?Low Resistance (e.g., 1k - 10k): Best for signals driving standard inputs (like Arduino pins) or to minimize noise interference. High Resistance (e.g., 250k - 1M): Best for high-impedance sources, such as electric guitar pickups, to prevent signal loss (loading) which preserves treble frequencies. 

Introduction In general, the radio is constructed by mechanical devices, electronic devices, magnets, etc. It receives the audio signals emitted by broadcasting stations through converting electric wave signals. After the invention of the vacuum tube, the circuit and receiving performance of the radio had undergone revolutionary progress and improvement, that is valve radio. Later, with the development of technology, radios with transistors as the core gradually became popular. It's what we know as a transistor radio. Radios are still widely used for many functions. Here two main radios will be described in detail below. Catalog Introduction Ⅰ Valve Tube Radio 1.1 Vacuum Tube Radio Classifications 1.2 Advantages and Disadvantages of Valve Radio 1.3 German Vintage Valve Radio Models for Sale Ⅱ Transistor Radio 2.1 Transistor Radio Overview 2.2 Transistor Radio Selection Matters 2.3 Transistor Radio Brands for Sale Ⅲ Radio Further Development Ⅳ FAQ Ⅰ Valve Tube Radio The valve radio, also known as the vacuum tube radio, was a product of the early 20th century, and immediately became the new favorite of that era with the launch of the broadcasting station. By the late 1920s, vacuum tube radio equipment replaced the primitive spark-gap systems on most merchant ships. This new equipment could send and receive signals virtually worldwide, by using high frequency or "short-wave" bands. Tube technology allowed radio signals to be tuned with much greater precision than spark-gap. The basic design for tube radio was perfected by the 1930s and continued in use on merchant vessels into the 1980s. 1.1 Vacuum Tube Radio Classifications 🔺AM (Amplitude Modulation) RadioIn the era when tube radios were popular, AM radios were the mainstream products. Amplitude modulation wave modulates the high-frequency carrier with audio signal. Its waveform is symmetrical, the amplitude is the same as that of the modulated signal, and then obtain the audio signal after high-frequency component is filtered out. In addition, the frequency of the carrier signal (the frequency of the broadcasting station) is the carrier frequency.AM radios can receive medium-wave and short-wave broadcasts, and some can receive long-wave broadcasts. Since the mid-band frequency interval has been unified to 9KHz, its highest audio frequency is only 4KHz. So the sound quality is affected because of large electromagnetic interference.There are two main types of AM radios: direct-amplifier type and external (self) differential type1) Direct-amp radio, also called high-amp radio, its typical circuit structure is as follows:High Amplifier—Detection—Low Amplifier—Power AmplifierA circuit that uses a grid detector circuit and high-frequency positive feedback is called a regenerative radio, which can obtain higher sensitivity and amplitude selectivity. A regenerative radio with high amplifier and short wave can receive AM telegraph signals. Most of the old Japanese-made radios have such circuits. Direct-amp radios are prone to self-excitation of high-frequency signals, high-end and low-end gains are uneven, and regenerative radios without high-amplification have poor selectivity. In addition, the reed speakers with poor sound quality are generally used, so they are gradually replaced by superheterodyne radios.Simple regenerative radios mostly use reed speakers, which have high impedance (about 10K) and high sensitivity. It can be directly used as the load of the power amplifier tube, but the frequency range is only 350~3000Hz, so the sound quality is poor. Later regenerative radios applied moving coil speakers, and the sound quality was better. However, because of low impedance, an output transformer is required, and its primary impedance must match the load impedance of the power amplifier tube. Moving coil speakers are divided into permanent magnets, constant magnets and excitation. Among them, excitation horns are used in AC electronic tube radios, and their excitation coils can also be used as filter chokes. 2) Heterodyne RadioThe heterodyne radio adopts a frequency conversion circuit. The signal generated by its high-frequency oscillation circuit and the input signal have a certain frequency difference. After the two are mixed, a fixed intermediate frequency signal (455~465KHz) is generated. Some people call the oscillation frequency higher than the signal frequency a heterodyne type, and vice versa.Heterodyne plus intermediate frequency amplifier circuit is called superheterodyne. This type of circuit requires a single electron tube to oscillate, and later a multi-pole or composite tube dedicated to frequency conversion appears. The superheterodyne type is the most common circuit of commercial radios. It has an automatic volume control circuit and can add tuning instructions. The circuit principle will be described in detail later. The superheterodyne radio can obtain more stable and higher gain due to amplifying the fixed frequency. The disadvantage is that there is image frequency interference.The circuit structure of a typical superheterodyne radio is as follows:Frequency Conversion—Middle Amplification—Detection—Low Amplification—Power Amplification 3) Autodyne Frequency Conversion RadioUsing ordinary pentodes for frequency conversion is only suitable for the mid-band, and the middle frequency is 175KHz. Due to the popularization of special frequency conversion tubes, it is rarely used now. Figure 1. Vintage AM Radio 🔺FM (Frequency Modulation) RadioFM radio is a radio that transmits radio signals through the use of FM frequency modulation carrier. Due to the shorter wavelength, the signal transmitted is much better than that of the radio that uses the AM wavelength. However, due to the short wave, the transmission distance is relatively short.FM wave is to use audio signal to modulate the frequency of high frequency carrier. Its advantages include strong anti-interference ability, high signal-to-noise ratio, good frequency bandwidth and sound quality, in addition, the audio frequency can reach 20Hz~15000Hz. Because the FM wave works in the ultra-high frequency band, it can accommodate many radio stations. With its linear propagation characteristics, the same frequency can be reused at a distance of hundreds of kilometers, which can effectively solve the problem of congestion of medium and short wave radio stations.Modern FM broadcasting is compatible with stereo and mono channels(in the early days of stereo broadcasting, two frequencies were used and two radios for reception). Some hobbyists are likely to use a simple super-regenerative circuit to receive FM broadcasts. Because it works in a self-oscillation state, the work is unstable and has strong super-noise. 1.2 Advantages and Disadvantages of Valve Radio Advantages of Valve Radio 1) The valve tube circuit has a simple structure and good anti-overload performance.2) The characteristics of the power amplifier circuit of the tube radio are better than those of the transistor or integrated circuit power amplifier. The screen current of the Class A power amplifier circuit with an output transformer for output impedance matching has little change at zero signal and full signal. So the performance is stable, the distortion of the line work area is very small, and the harmonic content is very rich .3) The speakers used in valve radios are generally larger in diameter than those of transistor or integrated circuit radios.4) The IF circuit characteristics of tube radios are better than those of transistor or integrated circuit radios.5) Have collection value. Disadvantages of Valve Radio As for the shortcomings, valve tubes that are large in size and used as basic components, built-in accessories are also bulky, power consumption has also increased, the overall quality has become poor, inconvenient to carry, and poor seismic performance. In addition, it is very difficult to make FM stereo radio devices, because early tube radios can only receive shortwave and medium waves. These shortcomings eventually led to the replacement of tube radios by transistor radios. Vintage Valve Radios - Will they work? 1.3 German Vintage Valve Radio Models for Sale AEG RadioBlaupunktGerman EMUDGraetz Vintage RadioGrundig Vintage RadioHornyphon Vintage RadioVintage Koerting RadioGerman Metz Vintage RadioVintage Nordmende RadioPhilips Vintage RadioVintage Saba RadioVintage Siemens RadioTelefunken Radio Figure 2. Vintage Valve Radio Ⅱ Transistor Radio 2.1 Transistor Radio Overview The transistor radio is the second generation radio after the valve radio. Compared with vacuum tubes, transistors are small in size, light in weight, resistant to vibration, long in life, and low in power consumption. This kind of radios can be made compact and have relatively stable performance. Therefore, after the advent of transistor radios, a large number of portable radios and pocket radios have emerged. They are very convenient for daily use. The Regency TR-1 was the first commercially manufactured transistor radio by developed by Texas Instruments and IDEA Inc., introduced in 1954.Transistor radios use transistors to process and amplify signals. Simple to use, it is a small transistor-based radio receiver. 2.2 Transistor Radio Selection Matters To choose a good transistor radio, you must first understand four basic relationships:1) The larger the chassis volume, the better the sound quality.2) The larger the horn diameter, the better the sound quality.3) The larger the battery volume, the longer the relative service life of the battery.4) The longer the magnetic bar, the higher the sensitivity.Secondly, we should also pay attention to five points when selecting:1) The change after the power supply voltage is reduced should be small. When selecting, you can have listening trial, because the impact on a high-quality radio should not be significant.2) The distortion of the offset radio should be small. After finding a radio station, having the left and right adjustments, the distortion should be small. In addition, there should be no whistling sound, otherwise, the frequency characteristics of the intermediate frequency part are poor.3) The volume change should be small when turning the button.4) Human body induction has little influence. When a person's body is close to the radio, it will have a certain impact on the work of the radio. This situation is particularly obvious for shortwave.5) The noise should be small. Noise generally includes electrical noise and mechanical noise. Turn the radio to a place where there is no station, and turn on the volume to the maximum. At this time, the minimum sound is better. Listen to a program to check whether there are noises caused by resonance of certain components when the volume is loud. Finally, you should also pay attention to whether the tuning knobs and buttons are coordinated and effective, and whether the shell of the radio is damaged or not. Vintage Transistor Radios Show And Tell 2.3 Transistor Radio Brands for Sale EdifierGAORUI HOME TEXTILESONYRoltonHALFSUNPandaSoaiyNintaus Figure 3. Regency tr-1 Transistor Radio Ⅲ Radio Further Development With the advent and development of integrated circuits, transistors have been replaced by integrated circuits, that is the third-generation radios invention, sometimes also known as semiconductor radios.After the radio uses integrated circuits, not only the size can be made smaller, but also the reliability is high. As the number of integrated circuit components is getting larger and larger, radios made with it have better performance and more functions. The integration of radios has become an inevitable trend.   Ⅳ FAQ 1. What is a vacuum tube radio?A vacuum tube, also called a valve in British English, is an electronic device used in many older model radios, television sets, and amplifiers to control electric current flow. The cathode is heated, as in a light bulb, so it will emit electrons. ... The anode is the part that accepts the emitted electrons. 2. Do valve radios still work?A valve radio will never be as reliable as a transistor set, and short of ripping out the chassis and replacing it with a transistor circuit, we aren't going to make it that reliable. However, some designs of valve set are more unreliable than others, and the main factor seems to be heat. 3. What did valves do in radios?The valve was useful as an electronic switch and its first use was in radio circuits detecting signals. The valve has two elements - a wire and a metal plate surrounded by a vacuum. The electricity flows between them. 4. How does a tube radio work?The basic working principle of a vacuum tube is a phenomenon called thermionic emission. It works like this: you heat up a metal, and the thermal energy knocks some electrons loose. 5. When did radios stop using vacuum tubes?1950s-60s - Most vacuum tubes were replaced by transistors in the west. 1970s-80s Tubes are still used in many specialized applications like broadcast television and radio. 6. Why did we stop using vacuum tubes?Vacuum tubes suffered a slow death during the 1950s and '60s thanks to the invention of the transistor—specifically, the ability to mass-produce transistors by chemically engraving, or etching, pieces of silicon. Transistors were smaller, cheaper, and longer lasting.A transistor is a semiconductor device used in electronic circuits as to function as "on" and "off" switching and amplifying device in the electronic circuits. ... Radio is a device which transmit and amplifies signals. The modern radio uses transistor since it is smaller in size. 7. Are transistor radios still being made?Transistor radio is an obsolete term now, carried over from when having transistors rather than tubes made small radios possible. It has come to be analogous to a portable, battery-powered radio, so while I will be making some recommendations, they likely will have integrated circuits, rather than transistors.It is a radio receiver which uses transistors to amplify the sound. Transistor radios can be cheap and small and some use very little electric power. Some can amplify the weak radio waves that are usually not picked up by weaker vacuum tube radios. 8. What does a transistor radio do?The function of transistors in radios is straightforward. Sounds are recorded through a microphone and turned into electrical signals. Those signals travel through a circuit, and the transistor amplifies the signal, which is subsequently much louder when it reaches a speaker. 9. Why was the transistor radio invented?One goal was to find a replacement for fragile and energy-wasting vacuum tubes. Building on war-time research, John Bardeen and Walter Brattain, working with group leader William Shockley, developed a device they called a transistor. 10. Where was the transistor radio invented?There was a tremendous push during the war to reduce the size and power consumption of vacuum tubes, particularly because the receivers used in radio-controlled bombs depended on vacuum tube technology. “Not long after the war ended, the transistor was developed at Bell Labs, in 1947. 11. What is the name of first transistor radio?Regency TR-1In July 1954 the Texas Instruments and Industrial Development Engineering Associates (I.D.E.A.) companies embarked on a six month project to produce a pocket-sized radio for the Christmas market. The result was the Regency TR-1, the world's first pocket transistor radio.

Ⅰ Introduction   A capacitor is an electrical device that stores energy as an electric field. It consists of two metal plates separated by a dielectric or non-conducting material. Fixed capacitance and variable capacitance are the two broad categories of capacitors. The most common are fixed capacitance capacitors, but variable capacitance capacitors are also available. Rotary or trimmer capacitors are examples of these. Fixed capacitance capacitors are classified as film capacitors, ceramic capacitors, electrolytic capacitors, and superconductor capacitors. Follow the link to learn more about the various types of capacitors. This article goes into greater detail about the ceramic capacitor.     Images of  Capacitors     Catalog Ⅰ Introduction Ⅱ Ceramic Capacitor Basics 2.1 What is a Ceramic Capacitor? 2.2 Ceramic Capacitor Polarity and Symbol 2.3 Types and Properties of Ceramic Capacitors 2.4 Ceramic Capacitor  Classes Ⅲ Why Ceramic Capacitors Mostly Used in Electronic Circuit than Others? 3.1 Applications and Uses of Ceramic Capacitor 3.2  Properties or Advantages of Ceramic Capacitors Ⅳ How to Read Ceramic Capacitor? 4.1 Where to Use a Ceramic Capacitor? 4.2 How We Read Ceramic Capacitor Value？ 4.3 Calculate Ceramic Capacitor Value 4.4 Some Examples Ⅴ FAQ     Ⅱ Ceramic Capacitor Basics   2.1 What is a Ceramic Capacitor?   The capacitor value is unchangeable.  The working ceramic material acts as the dielectric, and it is a ceramic capacitor constructed of two or more alternating layers of ceramic and it has a metal layer acting as the electrodes, and the composition of the ceramic material defines the electrical behavior and thus applications.   As per below video of ceramic capacitors:     What is CERAMIC Capacitor _ Uses _ complete information in English     2.2 Ceramic Capacitor Polarity and Symbol   Ceramic capacitors are the most common type of capacitor found in all electrical devices, and they use a ceramic material as the dielectric. Ceramic capacitors are non-polarity devices, which means they have no polarities. As a result, we can connect it to a circuit board in any direction.   As a result, they are far safer than electrolytic capacitors. The symbol for a non-polarised capacitor is shown below. Many capacitors, such as tantalum beads, do not have polarity.     Ceramic Capacitor Polarity and Symbol       2.3 Types and Properties of Ceramic Capacitors   Ceramic capacitors come in three varieties, though other styles are available:   Resin-coated leaded disc ceramic capacitors for through-hole mounting.Multi-Layer Ceramic Capacitors with Surface Mount (MLCC).Microwave bare lead-free disc ceramic capacitors that are designed to fit into a PCB slot.   different types of ceramic capacitors     Ceramic disc capacitors   Ceramic disc capacitors are made by coating a ceramic disc on both sides with silver contacts. These devices can be made from multiple layers to achieve higher capacitances. Ceramic disc capacitors are typically through-hole components that are dwindling in popularity due to their size. If capacitance values allow, MLCCs are used instead. Ceramic disc capacitors have capacitance values ranging from 10pF to 100F and voltage ratings ranging from 16 volts to 15 kV and higher.   Multi-layer ceramic capacitor (MLCC)   MLCCs are fabricated by precisely combining finely ground granules of paraelectric and ferroelectric materials and then layering the mixture with metal contacts. Following the completion of the layering, the device is heated to a high temperature and the mixture is sintered, resulting in a ceramic material with the desired properties. The resulting capacitor is essentially made up of many smaller capacitors connected in parallel to increase the capacitance. MLCCs have 500 layers or more, with a minimum layer thickness of about 0.5 microns. As technology advances, layer thickness decreases, and higher capacitances for the same volume are achieved.     2.4 Ceramic Capacitor  Classes   Different ceramic capacitor classes are defined based on the working temperature range, temperature drift, and tolerance:   Class 1 Ceramic Capacitors   These are the most temperature-stable capacitors. They have nearly linear properties.The most commonly used dielectric compounds are.Magnesium Titanate is used to achieve a positive temperature coefficient.Calcium Titanate is used in capacitors that have a negative temperature coefficient.   Class 2 Ceramic Capacitors   Class 2 capacitors perform better at the price of volumetric efficiency, but at the expense of lower accuracy and stability. As a result, they are typically used for decoupling, coupling, and bypass applications where precision is not critical.Temperature range: -50 to +85 degrees CelsiusThe dissipation factor is 2.5 percent.Accuracy ranges from average to poor.   Class 3 Ceramic Capacitors   Class 3 ceramic capacitors have a high volumetric efficiency but a low dissipation factor. It is unable to withstand high voltages. Barium Titanate is a common dielectric.Temperature range of +10C to +55C will cause a -22% to +50% change in capacitance for a Class 3 capacitor.Dissipation factor: 3 to 5%.It will have a low level of accuracy (typically 20% or -20/+80%).   Class 3 is typically used for decoupling or in other power supply applications where accuracy is not critical.     Ⅲ Why Ceramic Capacitors Mostly Used in Electronic Circuit than Others?   Many circuits, particularly electronic circuits, use ceramic capacitors, as you may have noticed. Ceramic capacitors are largely used over electrolytic or other capacitors.   Ceramic capacitors     3.1 Applications and Uses of Ceramic Capacitor   In electronic sensor circuits, ceramic capacitors are used.Ceramic capacitors are used in the transmission and reception of electronic signals.Ceramic capacitors are applied in circuits such as audio mixers, controllers, and equalizers.Ceramic capacitors are suitable for frequency-dependent circuits, such as electronic filter circuits, audio circuits, radio signal transmitters, and receiver circuits. Resonant circuits, like radio frequency communication system, needs ceramic capacitors, too.Ceramic capacitors are used in alternating current circuits for no polarity such as high voltage protection circuits, power circuit breakers, and so on.Ceramic capacitors are used in direct current motors to reduce radio frequency noise.Ceramic capacitors can also be used as Bypass Capacitors.Why Ceramic Capacitors mostly used in Electronic Circuit?     3.2  Properties or Advantages of Ceramic Capacitors   Ceramic capacitors are available in extremely small sizes, which is a significant benefit. Because of the numerous electronic circuits, in fact, most modern electronic circuits necessitate the use of small size capacitors.   Many critical electronic circuits necessitate the use of very small capacitors. Ceramic capacitors are available in a wide range of sizes.   Ceramic capacitors can provide very high stability; in fact, they offer a wide range of stability.   Ceramic capacitors have a low temperature coefficient and a higher voltage breakdown characteristic.        5. Ceramic capacitors are the best choice for high-frequency applications.     Ⅳ How to Read Ceramic Capacitor?   Two reference tables   MarkingCapacitance (pF)Capacitance (ìF)101100 pF0.0001 ìF221220 pF0.00022 ìF471470 pF0.00047 ìF1021,000 pF0.001 ìF2222,200 pF0.0022 ìF4724,700 pF0.0047 ìF10310,000 pF0.01 ìF22322,000 pF0.022 ìF47347,000 pF0.047 ìF104100,000 pF0.1 ìF224220,000 pF0.22 ìF474470,000 pF0.47 ìF1051,000,000 pF1 ìF2252,200,000 pF2.2 ìF4754,700,000 pF4.7 ìF     Letter printed capacitor indicate tolerance LetterToleranceA±0.05 pFB±0.1 pFC±0.25 pFD±0.5 pFE±0.5%F±1%G±2%H±3%J±5 %K±10%L±15%M±20%N±30%P–0%, + 100%S–20%, + 50%W–0%, + 200%X–20%, + 40%Z–20%, + 80%     4.1 Where to Use a Ceramic Capacitor?   Ceramic capacitors are applied in a variety of applications. It is primarily used for filtration. It is used in a signal or frequency circuit to filter and purify the signal. It can convert a direct current to a direct current. The ceramic capacitor is a genre of energy storage device. It stores the DC while passing the AC. This is what the ceramic capacitor looks like.     4.2 How We Read Ceramic Capacitor Value？     alphabetic code     The first is an alphabetic code that indicates the component's tolerance. The second is a numeric code that tells us the actual capacitance of the capacitor.   So let's take a look at our example right now. In our example, the value is 102 k. The first significant digit in the code is one, and the second significant digit is zero. As a result, these are the numbers in front of our multiplier.         How to read the values of Ceramic Capacitors?   4.3 Calculate Ceramic Capacitor Value   So, if we take your multiplier, which is two, and looks at the chart, that equals two zeros. As a result, we append two zeros to the end of the number. So, picofarad, it's 1000. Now, K represents our component tolerance, which in this case is plus or minus 10%. So that's how we figure out the capacitor's size and rating.   Now I'm going to show you how to use a multimeter to measure the capacitance of a capacitor. In this example, I'm using a capacitor with the numerical value 103 written on it, which equals 10-nanofarads.       nine ferrites   When you look at the display of what is rated, you'll notice that its practical rating is it works, and it has nine ferrites. So tolerances are around 10%. When you connect it to your actual multimeter, In this one, make sure you have an appropriate terminal. As you can see, I have the capacitance symbol in the bottom right-hand corner. Then, make sure your multimeter is set to the appropriate range. Then double-check that you've selected the correct option.   Ceramic disk capacitor codes table   Picofarad pFNanofarad nFMicrofarad FCode100.010.00001100150.0150.000015150220.0220.000022220330.0330.000033330470.0470.0000474701000.10.00011011200.120.000121211300.130.000131311500.150.000151511800.180.000181812200.220.000222213300.330.000333314700.470.000474715600.560.000565616800.680.000686817500.750.000757518200.820.00082821100010.00110215001.50.0015152200020.00220222002.20.002222233003.30.003333247004.70.0047472500050.00550256005.60.005656210000100.110215000150.01515222000220.02222333000330.03333347000470.04747368000680.0686831000001000.11041500001500.151542000002000.22542200002200.222243300003300.333344700004700.474746800006800.68684100000010001105150000015001.5154200000020002205220000022002.2225330000033003.3335470000047004.7475   The final number written on a ceramic capacitor is the power of ten multiplied by the first two numbers. If a ceramic capacitor has the code 682, First, look at the last number. So, as we can see, the final number is 2. The multiplier is now 102.   4.4 Some Examples   204 = 20×104 = 200000 PF 472 = 47×102 = 4700 PF 502 = 50×102 = 5000 PF 330 = 33×100 = 33 PF   [100 = 1] UNITS   1000 nanofarad(nF) = 1 microfarad(µF) 1 picofarad = 10-12farads. Nano= 10-9 Micro= 10-6 1 Nano Farad= 10-9 Farad 1 Microfarad (µF)= 10-6 Farad 1 nF = 1000 pF 1 pF = 0.001 nF   Example:   convert 15 nF to pF: 15 nF = 15 × 1000 pF = 15000 pF   Capacitor voltage code   0G4VDC0L5.5VDC0J6.3VDC1A10VDC1C16VDC1E25VDC1H50VDC1J63VDC1K80VDC2A100VDC2Q110VDC2B125VDC2C160VDC2Z180VDC2D200VDC2P220VDC2E250VDC2F315VDC2V350VDC2G400VDC2W450VDC2H500VDC2J630VDC3A1000VDC   Ⅴ FAQ   1. What is ceramic capacitor used for? Ceramic capacitors are used for all types of circuits in a number of applications. There are four main capacitor applications that are described in detail below: coupling, decoupling, smoothing, and filtering.   2. Do ceramic capacitors go bad? Like mica capacitors, ceramic capacitors also very rarely go bad. Do not replace ceramic disc capacitors unless you are sure one has gone bad. ... While replacing the capacitors, check the radio's resistors. Since you will be replacing the capacitors, you should snip one lead of each paper and electrolytic capacitor.   3. Why do ceramic capacitors fail? Ceramic capacitors can fail in a couple of ways. They can be mechanically damaged - too much physical stress (pressure on the part or the board is bent a little too much) can cause a crack. The capacitor will then develop short circuits between layers. It acts more like a resistor in that case.  4. When should you use a capacitor? Capacitors are widely used in electronic circuits for blocking direct current while allowing alternating current to pass. In analog filter networks, they smooth the output of power supplies. 5. What is the practical use of capacitor? The most common use for capacitors is energy storage. Additional uses include power conditioning, signal coupling or decoupling, electronic noise filtering, and remote sensing. Because of its varied applications, capacitors are used in a wide range of industries and have become a vital part of everyday life.  6. Why capacitor is not used as battery? Capacitors don't provide large amount of energy because they have less energy density than batteries. Capacitors are useful to provide short duration power requirements because they can be charged or discharged at a higher rate than the batteries. 

Introduction Linear Displacement Sensor, also called Linear Transducer or Linear Potentiometer Sensor, is a device used to monitor and measure linear position, which convert mechanical physical quantities into electrical signals. Linear potentiometer is a type of variable resistance sensor, designed to measure the displacement of a slider or wiper in a linear direction. Also known as a slider or pot, linear potentiometers produce a changing rate of resistance, dependent on the position of a slider or wiper. LVIT Linear Position Sensor Technology Catalog Introduction Ⅰ Linear Displacement Sensor Working Principle Ⅱ Linear Potentiometer Sensor Design Parameters Ⅲ Linear Transducer Applications Ⅳ Linear Displacement Sensor Types Recommendation Ⅴ Linear Potentiometer Sensor Installation Ⅵ Linear Transducer Operating Requirements Ⅶ Linear Displacement Sensor Use Matters Ⅷ FAQ Ⅰ Linear Displacement Sensor Working Principle The function of the linear displacement sensor is to convert the linear mechanical displacement into an electrical signal. In order to achieve this effect, the sensor slide rail is connected to a steady-state DC voltage, allowing a small current of microamperes to flow, and the voltage between the slide and the starting end is proportional to the length of the slide. Using the sensor as a voltage divider can minimize the requirements for the accuracy of the total resistance of the sliding rail, because the resistance change caused by the temperature change will not affect the measurement result. The linear displacement sensor is actually a sliding rheostat. Using the sensor as a voltage divider can minimize the requirements for the accuracy of the total resistance of the sliding rail, because the resistance change caused by the temperature change will not affect the measurement result. Figure 1. KTC 300mm Linear Displacement Sensor Ⅱ Linear Potentiometer Sensor Design Parameters For the general linear displacement sensor:Wear resistance life: >100X106 timesLinear accuracy error: <0.05%Repeatability error: <0.005mmMaximum moving speed: 10m/sImpact factor: IEC 68-2-29:1968 50gVibration factor: IEC 68-2-6:1982 20gMaximum allowable voltage: DC60V/5KΩ～20KΩ; DC36V/2KΩ～4KΩ; DC24V/1KΩTemperature drift coefficient: <1.5ppm/℃ Figure 2. KTR-75mm Linear Displacement Transducer Ⅲ Linear Transducer Applications 1) KTC, KTM, LS tie rod structure is a general structure, with optional pull ball universal head or universal head, can reduce the adverse effects caused by the installation of non-neutral. They are suitable for injection molding machines, textile machinery, woodworking machinery, etc.2) KPC and KPM fixed belts at both ends are hinged and sporty, suitable for swinging, and in measurement systems where the sensor body cannot be fixed, and the sensor will move with the measurement movement.3) KTF and KFM slider types are suitable for the application of the smallest installation length size. With the extension arm, it can eliminate the adverse effects of installation misalignment.4) KTR type is a miniature self-recovery rod structure, no need to tow and install.5) KPF type can also detect the internal displacement of the cavity. Figure 3. KPM Linear Displacement Sensor Ⅳ Linear Displacement Sensor Types Recommendation 🔺Tie Rod TypeUniversal drawbar conductive plastic film series, effective stroke 75mm ~ 1250mm, 4mm buffer stroke at both ends, precision 0.05%~ 0.04%FS. The surface of the shell is anodized, anti-corrosion.Built-in conductive plastic measuring unit, no temperature drift, long life, and automatic electrical grounding function. The sealing grade is IP67, DIN430650 standard plug and socket, which can be applied to most general occasions.The tie rod ball joint has 0.5mm automatic centering function, and the allowable extreme movement speed is 10m/s.🔺Sliding TypeGeneral-purpose slider conductive plastic film series, effective stroke 75mm～3000mm, 4mm buffer stroke at both ends, precision 0.05%～0.02%FS. The surface of the shell is anodized, anti-corrosion.Built-in conductive plastic measuring unit, no temperature drift, long life, and automatic electrical grounding function. The sealing level is IP54 (IP57 when installed downwards), DIN430650 standard plug and socket, which can be used in most general occasions, especially the length direction is limited, the alignment is difficult.The tie rod with the ball head has 10mm automatic correction function, and the allowable limit motion speed is 10m/s. Figure 4. KPC Linear Displacement Sensor Ⅴ Linear Potentiometer Sensor Installation 1) The installation of the linear displacement sensor should balance two ends. Do not tighten the fixing bracket screws before the limit position is determined. The linear displacement sensor fixing bracket screws can be locked after adjusting the stroke.2) The pull-ball universal head of the tie-rod displacement sensor allows a centering deviation with a radius of 1mm. Of course, the shorter the specification, the smaller the centering deviation is recommended.3) After fixing the linear displacement sensor, when retracting the tie rod, the cylindrical body of the universal ball head should be able to have gaps in the four radial directions. Or adjust the mounting position of the universal head or the mounting bracket position near the extended end.4) If there is a big misalignment when the pull rod is pulled out, adjust the mounting bracket near the end of the plug. This can be used as an auxiliary review method.5) The mounting rod of the pull ball universal head and the pull rod are allowed to tilt at an angle of 12°. However, if the centering deviation and tilt deviation are both large during installation, the stability and service life of the electronic ruler will be affected. So further adjustment is required.6) The slider electronic ruler can reduce the workload of adjusting the neutrality, but the auxiliary extension rod cannot be cancelled. Because the stability and service life due to the poor neutralization will occur, and even damage the sensor.7) After all adjustments are made, tighten the mounting screws to make the grounding resistance less than 1. Measure the resistance between the cover screw of the potentiometer sensor and the mounting bracket with a multimeter in the 200 block.8) When using a four-wire system or wiring with a shielded wire, the grounding end of the linear potentiometer should be connected, and the fourth end or shielding wire should be grounded at the end of the electric control box correctly. Figure 5. KTM Linear Displacement Sensor Ⅵ Linear Transducer Operating Requirements 🔺The supply voltage should be stable.Industrial power supply requires ±0.1% stability. For example, the reference voltage is 10V, and the fluctuation of ±0.01V is allowed under the fluctuating voltage. Otherwise, it will cause the displayed trap to fluctuate. 🔺Prevent electrostatic interference.Electrostatic interference and FM interference can easily make the digital display of the linear displacement sensor jump. Separate the strong current line of the equipment from the signal line of sensor in a wire duct. The potentiometer should use a grounding support, and its shell (the resistance between the end cover screw and the support should be less than 1Ω) must be well grounded. The signal line should be shielded and well grounded where at one end of the electrical box.In the case of electrostatic interference, the voltage measurement of the general multimeter is normal, but it shows the digital beating, even the phenomenon is the same when the high-frequency device is interfered. To verify whether it is electrostatic interference, use a power cord to short-circuit the cover screw of the sensor with a certain point of metal on the machine. However, it is difficult to eliminate high-frequency interference by the above-mentioned methods, which occurs frequently in robots and inverters. Stopping the robot or the inverter power saver can test it. 🔺WiringLines "1" and "3" are power lines, and "2" is the output line. Once the above line is connected wrongly, there will be large linear errors, resulting in poor control accuracy, and display bounce easily. 🔺The power supply capacity should be sufficient.If the power supply capacity is too small, the following situations are likely to occur: the mold clamping movement will cause the display of the glue injection ruler to jump, or the melt movement will cause the display of the mold clamping potentiometer sensor to fluctuate. Especially when the power supply of solenoid valve drive power supply is combined with the sensor, the above-mentioned situation is prone to occur. In severe cases, the voltage fluctuation can be measured with the voltage file of a multimeter. If the problem cannot be solved, even if the electrostatic interference and high-frequency interference are eliminated, the neutrality is also bad. At this time, you can check the power supply efficiency. 🔺Installation angleThe angle tolerance is ±12°, and the parallelism tolerance is ±0.5mm. If both are too large, it will cause the display number to jump. In this case, the angle and parallelism must be adjusted. 🔺Prevent short circuit.During the working process of the displacement sensor, the data is regularly displayed at a certain point or no data. In this case, it is necessary to check whether the connection line insulation is damaged and the ground short circuit caused by regular contact with the machine's metal casing. 🔺Avoid aging.For the linear displacement sensor that has been used for a long time, the seal is aging, there may be a lot of impurities, such as oil and water mixture, which affect the contact resistance of the brush, and cause the display number. It can be considered as the early damage of sensor. Figure 6. KTF Linear Displacement Sensor Ⅶ Linear Displacement Sensor Use Matters 1) If the potentiometer sensor has been used for a long time, and the seal has been aging, there are a lot of impurities mixed in, and the water mixture and oil will seriously affect the contact resistance of the brush, which will cause the displayed number to jump continuously. At this time, it can be said that the electronic ruler of the linear displacement sensor has been damaged and needs to be replaced.2) If the capacity of the power supply is small, there will be many situations. Therefore, the power supply should have sufficient capacity. Because insufficient capacity will cause the following situation: The movement of the melt will change the display of the sensor to cause the fluctuations,  resulting in a large error in the measurement result.If the driving power of the solenoid valve and the power supply of the linear displacement sensor are at the same time, the above situation is more likely to occur. In serious cases, the voltage range of the multimeter can even measure the relevant fluctuations of the voltage. If the situation is not caused by high-frequency interference, electrostatic interference, or insufficient neutrality, then it may be caused by the small power supply.3) FM interference and electrostatic interference may cause the digital scale of the linear displacement sensor to jump. The signal line of the sensor and the strong current line of the equipment should be separated from the wire duct. Use the grounding support to have good contact with the ground. The signal wire needs to use a shielded wire, and a section of the electrical box should be grounded to the shielded wire.If there is high-frequency interference, the voltage measurement with a multimeter will usually display abnormally. When there is electrostatic interference, the situation is the same as that of high-frequency interference. To prove whether it is electrostatic interference, you can use a power cord to short-circuit the cover screw of the sensor with some metal on the machine. As long as it is short-circuited, the e-interference will be eliminated immediately. However, if you want to eliminate high-frequency interference, it is difficult to use the above method. Frequency-conversion power savers and robots often have high-frequency interference, so you can try to stop them to verify the interference.4) The power supply voltage must be stable. The industrial voltage needs to meet the stability of ±0.1%. For example, if the reference voltage is 10V, a fluctuation of ±0.01V can be allowed. If it is not, it will cause a display fluctuation. But if the amplitude of the display fluctuation at this time does not exceed the amplitude of the fluctuation voltage, then the potentiometer sensor is normal.5) As for the linear displacement sensor installation, the parallelism can be allowed to have an error of ±0.5mm, and the angle can be allowed to have an error of ±12°. However, if both are too large, then the display number will be bounced. So the parallelism and angle must be adjusted.6) During the connection process, be sure to pay more attention, the wires of the potentiometer sensor cannot be connected wrongly.   Ⅷ FAQ 1. What is a linear displacement sensor?A linear displacement sensor is a device used to monitor and measure linear position. They can also be called Linear Position Sensors or Linear Transducers. They are available in different sizes to measure different stroke lengths.   2. How does a linear displacement sensor work?Linear displacement transducers are linear sensors that work on the magnetostrictive principle, whereby a torsional strain pulse is induced in a specially designed magnetostrictive waveguide by the momentary interaction of two magnetic fields.   3. What is the linear displacement?Therefore; “Linear Displacement” can be defined as the movement of an object in a linear fashion along a single axis in a straight line, for example; from side to side or up and down. ... Linear Displacement is usually measured in millimetres or inches and has a positive and negative direction.   4. What are linear sensor potentiometers?A linear potentiometer is a type of position sensor. They are used to measure displacement along a single axis, either up and down or left and right. Linear potentiometers are often rod actuated and connected to an internal slider or wiper carrier.   5. What is the difference between linear potentiometer and rotary potentiometer?This potentiometer is similar in function to the rotary potentiometer. The only difference between these two, as the name suggests, is the linear motion of the knob, instead of rotary, for adjusting the resistance.   6. How does a potentiometer sensor work?Potentiometers work by varying the position of a sliding contact across a uniform resistance. ... A potentiometer has the two terminals of the input source fixed to the end of the resistor. To adjust the output voltage the sliding contact gets moved along the resistor on the output side.   7. What does a potentiometer sensor measure?A potentiometer sensor measures the distance or displacement of an object in a linear or rotary motion and converts it into an electrical signal.   8. How does a potentiometer measure displacement?To measure the displacement of the body, this body, which is moving, is connected to the sliding element of the potentiometer. As the body moves, the position of the slider located on the potentiometer also changes so the resistance between the fixed point and the slider changes.

ⅠIntroduction Channel MOSFETs are a type of Metal Oxide Semiconductor Device. It consists of the n-substrate in the center with a high concentration of light doping. This is a list of the three-terminal devices. It has unipolar characteristics because the majority of the charge carriers are essential for its operation. Because of the two p materials used in the circuitry, the majority of the carriers are holes. It is further subdivided based on the presence of channels.   Catalog ⅠIntroduction Ⅱ What is P-Channel  MOSFET? Ⅲ P Channel MOSFET Characteristics Ⅳ How P-Channel MOSFETs Are Constructed Internally? Ⅴ Types of P-Channel MOSFET 5.1 P Channel with Enhancement MOSFET 5.1.1  How a P-Channel Enhancement-type MOSFET Works? 5.1.2 How to Turn on a P-Channel Enhancement Type MOSFET? 5.1.3 How to Turn Off a P-Channel Enhancement Type MOSFET? 5.2 P Channel Depletion MOSFET 5.2.1 How a P-Channel Depletion-type MOSFET Works? 5.2.2 How to Turn on a P-Channel Depletion Type MOSFET? 5.2.3 How to Turn Off a P-Channel Depletion Type MOSFET? Ⅵ How to use only positive voltage in this p-channel MOSFET tutorial? 6.1 VGS Threshold 6.2 P-Channel MOSFET Tutorial and Explanation Ⅶ FAQ     Ⅱ What is P-Channel  MOSFET?   A MOSFET is formed when a lightly doped N-type substrate is connected to two highly doped P-type materials. Doping refers to the concentration of impurities added to the atom. The p-channel formed between the two P-type substrates could be the consequence of induced voltages or it could have existed previously.    MOSFET Symbol    Ⅲ P Channel MOSFET Characteristics   The voltage controlled devices are represented by MOSFETs.These devices have high input impedance values.The conductivity of the channel in a P-channel is caused by the application of negative polarity at the gate terminal.     Ⅳ How P-Channel MOSFETs Are Constructed Internally?    P-Channel MOSFET   A P-Channel MOSFET is consists of a P channel, which is a channel that is mostly made up of hole current carriers. N-type material is used for the gate terminals.  How the transistor operates and whether it turns on or off  is determined by the amount and type of voltage (negative or positive)     P-Channel MOSFET as a Switch. Turn ON a 12V Motor with Arduino. (Step-By-Step Guide)     Ⅴ Types of P-Channel MOSFET   The p-channel MOSFET’s are classified as:   (1)P-channel with the Enhancement MOSFET (2) P-channel with the Depletion MOSFET     5.1 P Channel with Enhancement MOSFET   This MOSFET is constructed with a lightly doped n-substrate. The length separates the two heavily doped p-type materials (L). This L is referred to as the channel length.   Above the substrate, a thin layer of type silicon dioxide is deposited. This layer is commonly referred to as the dielectric layer. The source and drain are formed by the two P types. The gate terminal is formed by the aluminum plating used above the dielectric. The ground is connected to the source and the body of the MOSFET.   The gate terminal has been subjected to a negative voltage. Because of the effect of capacitance, the positive concentration of charges settles below at the dielectric layer. Because of repulsive forces, the electrons present at the n substrate are shifted, and the uncovered value of the positive ions layer can be found there. In an n-type substrate, the holes, which are minority carriers, combine with a few electrons to form a bond.   However, further application of the negative voltage cracks the covalent bonds, thereby breaking the pairs formed between electrons and holes. It results in the formation of holes and an increase in the carrier concentration of holes in the channel. When a negative voltage is applied to the drain terminal, the channel becomes conductive, allowing current to flow through the transistor.     5.1.1  How a P-Channel Enhancement-type MOSFET Works? circuit example     5.1.2 How to Turn on a P-Channel Enhancement Type MOSFET?     To turn on a P-Channel Enhancement-type MOSFET, apply a positive voltage VS to the MOSFET's source and a negative voltage to the MOSFET's gate terminal (the gate must be sufficiently more negative than the threshold voltage across the drain-source region) (VGDS). A current will be allowed to flow through the source-drain channel as a result of this.   With a sufficient positive voltage, VS, applied to the source and load, and a sufficient negative voltage applied to the gate, the P-Channel Enhancement-type MOSFET is fully functional and operating in the active 'ON' mode.     5.1.3 How to Turn Off a P-Channel Enhancement Type MOSFET?   There are two ways to turn off a P-channel enhancement type MOSFET. You can either disconnect the bias positive voltage, VS, which powers the source. Alternatively, you can disable the negative voltage applied to the transistor's gate.     5.2 P Channel Depletion MOSFET When compared to n channel depletion MOSFETs, the formation of p channel depletion is simply in reverse. Because of the presence of p-type impurities in the channel, it is pre-built. When a negative voltage is applied to the terminal gate, the free holes that represent the minority carriers at the n-type are attracted to the channel of the positive type impurity ions. When a drain terminal is reverse biased in this condition, the device begins to conduct, but as the negative voltage in the drain terminal increases, the depletion layer forms.   This region is affected by the concentration of the layer formed by positive ions. The width of the depletion region influences the conductivity of the channel. The current at the terminal is controlled by varying the voltage value of the region. Finally, the gate and drain retain their negative polarity, while the source maintains its zero value.     5.2.1 How a P-Channel Depletion-type MOSFET Works?   circuit  P-Channel Depletion-type MOSFET   5.2.2 How to Turn on a P-Channel Depletion Type MOSFET? The gate voltage feeding the gate terminal should be 0V for maximum operation if you switch on a P-Channel Depletion-Type MOSFET. The drain current is at its maximum when the gate voltage is 0V, and the transistor is in the active 'ON' region of conduction.     5.2.3 How to Turn Off a P-Channel Depletion Type MOSFET?   There are two methods for turning off a P-channel MOSFET. You can either switch off the bias positive voltage, VDD, which powers the drain, or you can turn it back on. Alternatively, you can apply a negative voltage to the gate. The current is cut down when a negative voltage is used to the gate. As the gate voltage, VG, becomes more negative, the current decreases until it reaches cutoff, at which point the MOSFET is in the 'OFF' state. It prevents a great source-drain current from flowing.   MOSFET transistors are applied for switching as well as amplifying. MOSFETs are among the most widely used transistors today. Because of their high input impedance, they draw very little input current, which is simple to manufacture, can be made very small, and consume very little power.       Ⅵ How to use only positive voltage in this p-channel MOSFET tutorial?   6.1 VGS Threshold   VGSth: an abbreviation for Voltage Threshold from Gate to Source is one of their critical properties we need to know about using MOSFETs. The resistance between the DRAIN and SOURCE pins changes as the voltage difference between those two pins changes. This is the threshold at which a MOSFET turns on and off.   The resistance changes depending on whether the MOSFET is N-Channel or P-Channel.     6.2 P-Channel MOSFET Tutorial and Explanation   For a P-Channel MOSFET, look at the VGSth. VGSth is a negative value, as you may have noticed. As an example, consider the datasheet for an IRF5305.     specification   The specification of VGSth is -2.0V to -4.0V. So, how could this MOSFET work with an Arduino, LaunchPad, Raspberry Pi, or any other microcontroller? Is it really necessary to generate negative voltages?     It’s about the difference:   This is where the "negative voltage" myth comes into play: Because the datasheet says negative, you need negative voltage to work. Datasheets, on the other hand, never lie (except when they do...).   Let's take a literal look at what the specification says. "A negative four-volt voltage from gate to source." You could read it as "GATE voltage value minus SOURCE voltage value" in other words.   Consider the following voltages in this "high-side switch" configuration:     negative voltage     The GATE now has a voltage of 5 volts. The SOURCE is 5 volts as well. It means that the Vgs is 5V – 5V = 0V. In this case, the Vgs is 0 volts. This voltage indicates that the MOSFET is off, or that it is open.   This is the same circuit as before, but the GATE is now connected to ground rather than 5 volts.       circuit  example in 5 volts     Let's take another look at the SOURCE and GATE. The SOURCE remains at 5 volts. However, the GATE is now at the ground, indicating that it is 0V. If you subtract the GATE voltage from the SOURCE voltage, you get 0V – 5V = -5V. This will activate the MOSFET.   Have you noticed what just happened? Using only positive voltage supplies, we obtained a "negative" voltage...     Why use N-Channel over P-Channel?   A tutorial on when to use an n-channel and p-channel MOSFET would be required. A great application for P-Channel is in a circuit where the voltage levels of your load and logic are the same. For example, suppose you're attempting to activate a 5-volt relay with an Arduino. The current required by the relay coil is too high for an I/O pin, but the coil requires 5V to function. Use a P-Channel MOSFET to turn on the relay from the Arduino's I/O pin in this case.   If your load voltage is higher, such as 12 or 24V, you should consider using an N-Channel MOSFET in a "low side" configuration.   Ⅶ FAQ   1. How do you test P MOSFET? Hold the MosFet by the case or the tab but don't touch the metal parts of the test probes with any of the other MosFet's terminals until needed. 2) First, touch the meter positive lead onto the MosFet's 'Gate'. 3) Now move the positive probe to the 'Drain'. You should get a 'low' reading.   2. When would you use a MOSFET? Power MOSFETs are commonly used in automotive electronics, particularly as switching devices in electronic control units, and as power converters in modern electric vehicles. The insulated-gate bipolar transistor (IGBT), a hybrid MOS-bipolar transistor, is also used for a wide variety of applications.   3. What is MOSFET? MOSFET stands for metal-oxide-semiconductor field-effect transistor. It is a field-effect transistor with a MOS structure. Typically, the MOSFET is a three-terminal device with gate (G), drain (D) and source (S) terminals.   4. What are the types of MOSFET? Different Types of MOSFET Transistors PMOS Logic. As previously mentioned, the integration of a MOSFET allows for high levels of circuit efficiency when compared with BJTs. ... NMOS Logic. ... CMOS Logic. ... Depletion Mode MOSFET Devices. ... MISFETs. ... Floating-Gate MOSFETs (FGMOS) ... Power MOSFETs. ... DMOS.                  

Introduction The rectifier diode is a semiconductor device that converts AC into DC. Usually it contains a PN junction with two terminals, a positive electrode and a negative electrode. The most important characteristic is unidirectional conductivity. In electronic circuits, its breakdown voltage is high, the reverse leakage current is small, and the high temperature performance is good. Generally, it can be made of materials such as semiconductor germanium or silicon. In addition, high-voltage and high-power rectifier diodes are made of high-purity single crystal silicon (it is easy to reverse breakdown when there is more doping). This kind of device has a large junction area and can pass a large current (up to thousands of amperes), but the operating frequency is not high, generally below tens of KHz. Rectifier diodes are mainly used in various low-frequency half-wave rectifier circuits. If require full-wave rectification, several diodes need to be connected to form a rectifier bridge. What is a Rectifier? (AC to DC) Catalog Introduction Ⅰ Common Parameters Ⅱ Rectifier Diodes Selection Ⅲ Rectifier Common Failures Ⅳ Rectifier Diodes Detection Ⅴ Rectifier Diode Replacement 5.1 Replacing Rules 5.2 Commonly Used Rectifier Models List Ⅵ Rectifier Diode Circuit Types 6.1 Half-Wave Rectifier Circuit 6.2 Full-Wave Rectifier Circuit 6.3 Bridge Rectifier Circuit Ⅶ High-frequency Rectifier Diodes Ⅷ FAQ Ⅰ Common Parameters The rectifier diode uses the unidirectional conductivity of the PN junction to convert alternating current into pulsating direct current. Rectifier diodes have a large leakage current, and most of them are diodes packaged with surface mount materials. The parameters of the rectifier diode include the maximum rectifier current, which refers to the maximum current value allowed by the rectifier diode for long-term operation. It is the main parameter of the rectifier diode and the main basis for the option of the rectifier diode. Except it, other important parameters are introduced here.(1) Maximum average rectified current IF: It refers to the maximum forward average current allowed to pass through the diode during long-term operation. The current is determined by the PN junction area and the heat dissipation conditions. It should be noted that the average current passing through the diode cannot be greater than this value, and has heat dissipation.(2) Maximum reverse working voltage VR: It refers to the maximum reverse voltage allowed to be applied across the diode. If it is greater than this value, the reverse current (IR) will increase sharply, and the unidirectional conductivity of the diode will be destroyed, causing reverse breakdown. Usually take half of the reverse breakdown voltage VB as VR.(3) Maximum reverse current IR: It is the reverse current allowed to flow through the diode under the highest reverse working voltage. This parameter reflects the quality of the unidirectional conductivity of the diode. Therefore, the smaller the current value, the better the diode quality.(4) Breakdown voltage VB: It refers to the voltage value at the sharp bend point of the reverse volt-ampere characteristic curve of the diode. When the reverse is a soft characteristic, it refers to the voltage value under a given reverse leakage current condition.(5) The highest operating frequency fm: It is the highest operating frequency of the diode under normal conditions. It is mainly determined by the junction capacitance and diffusion capacitance of the PN junction. If the operating frequency exceeds fm, the unidirectional conductivity of the diode will not be well reflected.(6) Reverse recovery time trr: It refers to the reverse recovery time under the specified load, forward current and maximum reverse transient voltage.(7) Zero-bias capacitor CO: It refers to the sum of the capacitance of the diffusion capacitance and the junction capacitance when the voltage across the diode is zero. It is worth noting that, due to the limitation of the manufacturing process, even the same type of diode has a large dispersion of its parameters. The parameters given in the manual are often within a range. If the test conditions change, the corresponding parameters will also change. For example, the IR of the 1N5200 series silicon plastic rectifier diode measured at 25°C is less than 10uA, and at 100°C IR becomes less than 500uA.     Ⅱ Rectifier Diodes Selection Rectifier diodes are generally planar silicon diodes, which are used in various power rectifier circuits. When selecting a rectifier diode, the parameters such as its maximum rectifier current, maximum reverse working current, cut-off frequency and reverse recovery time should be mainly considered.The rectifier diode used in the ordinary series stabilized power supply circuit does not require high reverse recovery time of the cut-off frequency. The rectifier diode with the maximum rectified current and maximum reverse working current should meet the requirements of the circuit.The rectifier diode used in the rectifier circuit of the switching regulated power supply and the pulse rectifier circuit should be a rectifier diode with a higher operating frequency and shorter reverse recovery time (such as RU series, EU series, V series, 1SR series, etc.) or select fast recovery diodes, or Schottky rectifier diode.     Ⅲ Rectifier Common Failures (1) Inadequate lightning protection and poor overvoltage protection. The rectifier device is not equipped with lightning protection and overvoltage protection devices. Or insufficient routine maintenance of the equipment.(2) Poor operating conditions. In the indirect drive generator set, because the calculation of the speed ratio is incorrect or the ratio of the diameters of the two belt pulleys does not meet the requirements of the speed ratio, the generator runs at a high speed for a long time, so the rectifier is at a higher voltage for a long time. It accelerates the rectifier aging, and was damaged by premature breakdown.(3) Poor operation management. The load failure or diode breakdown doesn’t fixed in time.(4) Poor equipment installation or manufacturing process. The generator set has been operating under large vibration for a long time, which affects the rectifier tube operation. At the same time, because the generator set speed is unstable, the working voltage of the rectifier tube also fluctuates, which greatly accelerate the aging and damage of the rectifier tube.(5) The specifications and models of the rectifier tube do not match. When replacing a new rectifier tube, wrongly replace the tube whose working parameters do not meet the requirements or the wiring is wrong, causing the rectifier tube to breakdown and damage.(6) The safety margin of the rectifier tube is too small. The overvoltage and overcurrent safety margin of the rectifier tube is too small, so that the rectifier tube cannot withstand the overvoltage or the peak value of the overcurrent transient process that occurs in the generator excitation circuit and is damaged. Figure 1. Diode as Rectifier Symbol     Ⅳ Rectifier Diodes Detection Here is a more general and simple method. Remove all the rectifier diodes in circuit, use the 100×R or 1000×R ohm range of a multimeter to measure the two lead wires of the rectifier diode (adjust and test twice). If the resistance values measured twice are very different, for example, the resistance value is as high as a few hundred kΩ to infinity, or the resistance value is only a few hundred Ω or less, indicating that the diode is good (except under special circumstances). If the resistance value measured twice is almost the same and the resistance value is very small, it means that the diode has been broken down and cannot be used. In addition, if the resistance values measured twice are both infinite, it means that the diode has been internally disconnected and cannot be used.     Ⅴ Rectifier Diode Replacement   5.1 Replacing Rules After the rectifier diode is damaged, you should replace with the same model or another model with the same parameters.Generally, rectifier diodes with high withstand voltage (reverse voltage) can be substituted for rectifier diodes with low withstand voltage, while rectifier diodes with low withstand voltage cannot be replaced with rectifier diodes with high withstand voltage. A diode with a high rectification current value can be substituted for a diode with a low rectification current value, while a diode with a low rectification current value cannot be substituted for a diode with a high rectification current value.   5.2 Commonly Used Rectifier Models List Material Model Reverse Voltage Operation (peak) Average Rectified Current   Silicon Rectifier Diode 1N4001 50V 1A (Ir=5uA,Vf=1V,Ifs=50A) 1N4002 100V 1A 1N4003 200V 1A 1N4004 400V 1A 1N4005 600V 1A 1N4006 800V 1A 1N4007 1000V 1A 1N4148 75V 4PF, Ir=25nA,Vf=1V 1N5391 50V 1.5A (Ir=10uA,Vf=1.4V,Ifs=50A) 1N5392 100V 1.5A 1N5393 200V 1.5A 1N5394 300V 1.5A 1N5395 400V 1.5A 1N5396 500V 1.5A 1N5397 600V 1.5A 1N5398 800V 1.5A 1N5399 1000V 1.5A 1N5400 50V 3A (Ir=5uA,Vf=1V,Ifs=150A) 1N5401 100V 3A 1N5402 200V 3A 1N5403 300V 3A 1N5404 400V 3A 1N5405 500V 3A 1N5406 600V 3A 1N5407 800V 1A (Ir=5uA,Vf=1V,Ifs=50A) 1N5408 1000V 1A   Ⅵ Rectifier Diode Circuit Types The power grid supplies users with alternating current, and various electrical devices require direct current. Rectification is the process of converting AC into DC. Utilizing the device with unidirectional conductivity, the current of alternating direction and magnitude can be converted into direct current. The following introduces three main rectifier circuits composed of crystal diodes.   6.1 Half-Wave Rectifier Circuit Figure 2. Half-Wave Rectifier Circuit The figure shows the simplest rectifier circuit. It is composed of power transformer B, rectifier diode D and load resistor Rfz. The transformer transforms the voltage into the required alternating voltage e2, and then D transforms the AC into pulsating DC.The transformer threshold voltage e2 is a sine wave voltage whose direction and magnitude change with time, and its waveform is shown in Figure (a). In the 0~K time, e2 is a positive half cycle, that is, the upper end of the transformer is positive and the lower end is negative. At this time, the diode is in forward conductive conduction, and e2 is added to the load resistor Rfz through it. Within π~2π, e2 is in negative half cycle, the lower end of the transformer secondary is positive, and the upper end is negative. At this time, D bears the reverse voltage and does not conduct, and there is no voltage on Rfz. In the time of π~2π, the process of 0~π time is repeated, and in the time of 3π~4π, the process of π~2π time... half-cycle through Rfz, a single right direction voltage is obtained on Rfz (up positive and lower negative), as shown in Figure (b), which achieves the purpose of rectification. But the load voltage Usc, and the load current also changes with time, so it is usually called pulsating DC. Figure 3. Half-Wave Rectifier Wave This rectification method of removing the first half week and leaving half a week is called half wave rectification. It is not difficult to note that the half-wave rectification is at the expense of consuming half of the AC in circuit, and the current utilization rate is very low. According to it, half-wave rectifier diode is commonly used in high voltage and small current occasions, and is rarely used in general radio devices.   6.2 Full-Wave Rectifier Circuit Figure 4. Full-Wave Rectifier Circuit If some adjustments are made to the structure of the rectifier circuit, a full-wave rectifier circuit that can be obtained. The figure above is the electrical schematic diagram of the full-wave rectifier circuit.The full-wave rectifier circuit can be regarded as a combination of two half-wave rectifier circuits. A tap needs to be drawn in the middle of the secondary coil of the transformer to divide the secondary coil into two symmetrical windings, so as to get two voltages e2a and e2b of equal size but opposite polarity to form two energized circuits.The working principle of the full-wave rectifier circuit can be illustrated by the waveform diagram. Between 0 and π, e2a is a positive voltage to Dl, D1 is turned on, and a up positive and down negative voltage is obtained on Rfz. e2b is a reverse voltage to D2, and D2 is not conductive (see Figure(b) ). In the time of π-2π, e2b is a positive voltage to D2, D2 is turned on, and the voltage obtained on Rfz is still up positive and down negative voltage, therefore e2a is a reverse voltage to D1, and D1 is not conductive (see figure (c). Figure 5. Full-Wave Rectifier Circuit Wave Repeated this way, because the two rectifier elements D1 and D2 conduct electricity in turn, the result is that the load resistor Rfz has the same direction of current at the positive and negative half cycles, as shown in Figure(b). This is full-wave rectification, which not only uses the positive half-cycle, but also cleverly uses the negative half-cycle. Full-wave rectifier greatly improves the rectification efficiency. Figure 6. Full-Wave Rectifier Circuits This circuit requires the transformer to have a secondary center tap that makes the two ends symmetrical, which brings a lot of trouble to the production. In addition, in this circuit, the maximum reverse voltage that each rectifier diode can withstand is twice the maximum value of the transformer secondary voltage, so diodes should withstand higher voltages.   6.3 Bridge Rectifier Circuit Figure 7. Bridge Rectifier Circuit The bridge rectifier circuit is the most used rectification circuit. It has the advantages of a full-wave rectifier circuit as long as two diode ports are connected to form a bridge structure, so its shortcomings are overcome to a certain extent.The bridge rectifier circuit is as follows: Figure 8. Bridge Rectifier Circuit (a) When e2 is a positive half cycle, D1, D3 and the direction voltage, D1, D3 are turned on; D2, D4 are applied with reverse voltage, they are turned off. E2, Dl, Rfz, and D3 are energized a loop in the circuit. On Rfz, a positive and negative half-wave washing voltage is formed. When e2 is a negative half cycle, a positive voltage is applied to D2 and D4, and they are turned on; Apply reverse voltage to D1 and D3, they are cut off. E2, D2Rfz, and D4 are energized a loop in the circuit, and the other half-wave rectified voltage is also formed on Rfz. Figure 9. Bridge Rectifier Circuit (b) If repeated, a full-wave rectified voltage at Rfz is made. The waveform diagram is the same as the full-wave rectifier. It is not difficult to see from the figure that the reverse voltage of each diode in the bridge circuit is equal to the maximum value of the secondary voltage of the transformer, which is half smaller than the full-wave cleaning circuit.     Ⅶ High-frequency Rectifier Diodes The rectifier diode in the switching power supply must have the characteristics of low forward voltage reduction and fast recovery, and should also have sufficient output power. The following three types of high-frequency diodes can be used: fast recovery rectifier, ultra-fast recovery rectifier, and Schottky diode rectifier.Fast recovery and ultra-fast recovery rectifier diodes have moderate and high forward voltage drop, and the range is from 0.8 to 1.2V. These two types of rectifier diodes also have higher cut-off voltage parameters. Therefore, they are particularly suitable for use in low-power auxiliary power circuits with output voltages around 12V.Compared with general rectifier diodes, the reverse recovery time difference between fast recovery rectifier diodes and ultra-fast recovery rectifier diodes is reduced to the nanosecond level, thus greatly improving the efficiency of the power supply. According to experience, when choosing a fast recovery rectifier diode, its reverse recovery time should be at least 1/3 of the rise time of the switching transistor. These two kinds of rectifier diodes also reduce the switching voltage spike, because it will affect the ripple of the output DC voltage.Whether fast recovery rectifier diodes and ultra-fast recovery rectifier diodes used in switching power supplies need a heat sink, which depends on the maximum power of the circuit. Under normal circumstances, the allowable junction temperature is 175°C during manufacture. The manufacturer has a technical parameters provided for the designer to calculate the maximum output operating current, voltage, and case temperature. Even under the action of a large forward current, the forward voltage drop of Schottky rectifier diodes is very low, only about 0.4V. Moreover, as the junction temperature increases, its forward voltage drop decreases. Therefore, Schottky rectifier diodes are particularly suitable for low-voltage output circuits around 5V. Its reverse recovery time is negligible, because this device is a semiconductor device with majority carrier. During the switching process of the device, there is no need to remove the stored charge of the minority carrier.Schottky rectifier diodes have two major shortcomings: First, the reverse cut-off voltage tolerance is low, about 100V; second, the reverse leakage current is large, making the device more susceptible to have heat breakdown than other types of rectifier devices. Of course, these shortcomings can also be overcome by adding a transient overvoltage protection circuit and appropriately controlling the junction temperature.     Ⅷ FAQ 1. How does a rectifier diode work?A rectifier is a device that converts an Alternating Current (AC) into a Direct Current (DC) by using one or more contact diodes. ... In simple words, a diode allows current in just one direction. This unique property of the diode allows it to act sort of a rectifier by converting an alternating current to a DC source.   2. What is a function of rectifier diode?A rectifier diode is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC).   3. What is the function of diode in rectifier circuit?A characteristic of diodes is that current flows (forward direction) or current does not flow (reverse direction) depending on the direction of applied voltage. This works to convert alternating current (AC) voltage to direct current (DC).   4. Which is used as rectifier?We know that the core use of rectifier is to convert AC current into DC current. The rectifier consists of semiconductor diodes to do this function.   5. What is the limitation of a diode rectifier?Disadvantages of Full Wave Bridge RectifierIt needs four diodes. The circuit is not suitable when a small voltage is required to be rectified. It is because, in this case, the two diodes are connected in series and offer double voltage drop due to their internal resistance.   6. What is the ideal rectifier diode efficiency?It is the ratio of DC output power to the AC input power. The rectifier efficiency of a full-wave rectifier is 81.2%.   7. What is a fast recovery rectifier?Definition: Fast Recovery Diode is a semiconductor device which possesses short reverse recovery time for rectification purpose at high frequency. A quick recovery time is crucial for rectification of high-frequency AC signal. Diodes are mostly used in rectifiers because they possess ultra-high switching speed.   8. Which diode is fast recovery diode?FRD stands for fast recovery diodes. They offer high-speed support and generally have a trr of approximately 50 to 100 ns. With a VF of approximately 1.5V, it is rather large when compared to general rectifying diodes. Another generic term for the FRD type would be a “High-speed Diode.”   9. What is ultra fast recovery diode?A fast diode is a faster-than-standard current rectifier. ... A fast rectifier typically recovers ten times faster than a standard rectifier, and an ultrafast designation is usually applied to rectifiers designed to beat the standard rectifier recovery by being more than fifty times faster.   10. What is the difference between a Schottky diode and a rectifier diode?Schottky diode, also known as barrier diode is mainly used in low voltage circuits because the forward voltage drop of Schottky diode(Vf) is less than a rectifier diode. The forward voltage drop of a Schottky diode is typically in the range of . 25 to 0.5 V whereas the Vf of a rectifier diode is around 0.7 volts.   11. What is Schottky barrier rectifier?The Schottky diode or Schottky Barrier Rectifier is named after the German physicist Walter H. Schottky, is a semiconductor diode designed with a metal by the semiconductor junction. It has a low-forward voltage drop and a very rapid switching act. ... Actually, it is one of the oldest semiconductor devices in reality.