IntroductionA stable power supply is necessary for normal operation of the electrical system. Except for the use of solar cells or chemical batteries in certain special occasions, the direct current of most circuits is converted from the alternating current of the grid. The bridge rectifier is commonly used to convert AC into DC, which is the most commonly used circuit that uses the unidirectional conductivity of diodes for rectification. There are many types of bridge rectifiers: flat, round, square, bench-shaped (plug in and SMD), etc., having GPP and O/J structures. The maximum rectified current ranges from 0.5A to 100A, and the maximum reverse peak voltage ranges from 50V to 1600V.What is Bridge Rectifier?CatalogIntroductionⅠ Bridge Rectifier Diode CircuitⅡ Bridge Rectifier Circuit FeaturesⅢ Single Phase Rectification vs Three Phase Rectification3.1 Single Phase Bridge Rectifier Circuit3.2 Three Phase Bridge Rectifier CircuitⅣ Role of Bridge RectificationⅤ Bridge Rectifier Wiring DiagramⅥ Difference between Bridge Rectifier and Full-wave Rectifier CircuitⅠ Bridge Rectifier Diode CircuitThe bridge rectifier uses four semiconductor diodes to be connected in pairs. When the positive half of the input sine wave is turned on, the two tubes are turned on, and the positive output is obtained; on the contrary, when the negative half of the sine wave is input, the other two tubes are turned on. Since the two tubes are reversely connected, the output is still the positive part of the sine wave. In addition, the utilization efficiency of the input sine wave by the bridge rectifier is twice as high as that of the half-wave rectifier.The rectifier bridge stack is generally used in a full-wave rectifier circuit, and it is divided into a full bridge and a half bridge. The full bridge is composed of 4 rectifier diodes connected in the form of a bridge full-wave rectifier circuit and packaged as a whole. The half bridge is to seal the half of the two diode bridge rectifiers together. Two half bridges can form a bridge rectifier circuit, and a half bridge can also form a full wave rectifier circuit with a center tap of the transformer. When choosing a rectifier bridge, the rectifier circuit and operating voltage must be considered carefully.The forward current of the full bridge has various specifications such as 0.5A, 1A, 1.5A, 2A, 2.5A, 3A, 5A, 10A, 20A, 35A, 50A, etc. The withstand voltage (the highest reverse voltage) is 25V, 50V, 100V, 200V, 300V, 400V, 500V, 600V, 800V, 1000V, etc.In this chapter, the rectifier diode is regarded as an ideal component, that is, its forward conduction resistance is considered to be zero, and its reverse resistance is infinite, because of the convenience of analyzing the rectifier circuit. However, in practical applications, it should be considered that the diode has internal resistance, and the output amplitude of the waveform obtained after rectification will be reduced by 0.6~1V. When the input voltage of the rectifier circuit is large, this part of the voltage drop can be ignored. On the contrary, if the input voltage is small, for example, if the input is 3V, the output is only 2V, and the influence of the diode forward voltage drop needs to be considered.Current Direction of the Bridge Rectifier CircuitFigure 1.In the positive half cycle of u2, D1 and D3 are turned on, D2 and D4 are turned off, and the current returns from the upper end of the TR secondary to the lower end via D1→RL→D3, and a half-wave rectified voltage is obtained on the load RL.In the negative half cycle of u2, D1 and D3 are off, D2 and D4 are on, and the current returns from the lower end of Tr secondary to the upper end of Tr secondary via D2→RL→D4, and the other half-wave rectified voltage is obtained on the load RL. Ⅱ Bridge Rectifier Circuit Features(1) The rectification device used is twice that of full-wave rectification.(2) Rectified voltage pulse changing direction is the same as full-wave rectification.(3) The reverse voltage that each device bears is the peak value of the power supply voltage.(4) The utilization rate of the transformer is higher than that of the full-wave rectifier circuit. Ⅲ Single Phase Rectification vs Three Phase Rectification3.1 Single Phase Bridge Rectifier CircuitFigure 2.The single phase bridge rectifier circuit is composed of four diodes connected in the form of a bridge. Its disadvantage is that it only uses half a cycle of the power supply, and at the same time the rectification voltage has a large pulsation.The above Figure 2 (a) shows the direction of current in the single-phase bridge rectifier circuit. The solid arrow indicates the situation when the AC power supply is in the positive half cycle, and the dotted arrow indicates the situation when the AC power supply is in the negative half cycle.It can be seen that the four diodes are divided into two parts: positive half cycle and negative half cycle. However, the current direction on the load does not change. This is full-wave rectification. In addition, the single-phase bridge rectifier circuit can be implemented with an integrated device "bridge stack" in practice.In Figure 3. shows the waveform diagram of the single phase bridge rectifier circuit. According to the diagram, the average voltage is: Uo ≈ 0.9U2 (where U2 is the effective value of the output voltage of the transformer secondary side).Figure 3. Wave Form (single phase)3.2 Three Phase Bridge Rectifier CircuitFigure 4.The three phase bridge rectifier circuit is developed from a uncontrolled half-wave rectifier circuit, which is essentially a series connection of a set of common cathode and a set of common anode with three semiconductor diodes.In addition, the three phase bridge circuit must have two thyristors turned on at the same time, one in the common cathode area and the other in the common anode area to form a loop.Circuit Analysis LawThe diode with the highest anode potential in the common cathode group is turned on.The diode with the lowest cathode potential in the common anode group is turned on.Circuit Analysis ExamplesFigure 5. t1 ~ t2In the common cathode group, the potential at point U is the highest, and V1 is on.In the common anode group, the potential at point V is the lowest, and V4 is on.The voltage across the load is the line voltage Uuv. Figure 6. t2~t3In the common cathode group, the potential at point U is the highest, and V1 is on.In the common anode group, the potential at point W is the lowest, and V6 is turned on.The voltage across the load is the line voltage Uuw. Figure 7. t3~t4In the common cathode group, the potential at point V is the highest, and V3 is on.In the common anode group, the potential at point W is the lowest, and V6 is turned on.The voltage across the load is the line voltage Uvw.......SummeryIn a full-wave cycle, it can be divided into 6 intervals, each of which is powered by a pair of phase wires to the load.In a full-wave cycle, each diode is turned on for one-third of the time (the conduction angle is 120°).During the 6 periods in a cycle, the voltage of the load can be seen as a periodic change. Ⅳ Role of Bridge Rectification1. Convert the alternating current generated by the alternator into direct current to power the electrical equipment and charge the battery.2. Limit the battery current to flow back to the generator to protect the generator from being burnt out by the reverse current.Figure 8. Bridge Rectifier AC to DC Flow ChartⅤ Bridge Rectifier Wiring DiagramThe bridge rectifier circuit overcomes the shortcomings that the full-wave rectifier circuit requires the transformer secondary to have a center tap and the diode to withstand large reverse voltage, but two diodes are used. With the rapid development of semiconductor devices and low cost today, this shortcoming is not obvious, so bridge rectifier circuits are widely used in practice.It needs to be pointed out that the diode as a rectifier component should be selected according to different rectification methods and load values. If choose improperly, you may not be able to work safely, or even burn the pipe, causing waste.Figure 9. Schematic Diagram of Bridge Rectifier CircuitThe bridge rectifier circuit can also be considered as a kind of full-wave rectifier circuit. The transformer is connected to four diodes according to the method shown in Figure 9. D1～D4 are four identical rectifier diodes connected in the form of a bridge, so they are called bridge rectifier circuits. Using the guiding function of the diode, the secondary output can be directed to the load even in the negative half cycle. It can be seen from the figure that D1 and D2 lead the current through RL from top to bottom during the positive half cycle, and D3 and D4 lead the current through RL from top to bottom during the negative half cycle. In this structure, if the same DC voltage is output, the secondary winding of the transformer needs only half of the winding compared with the full-wave rectification. However, if the same amount of current is to be output, the diameter of the winding should be increased accordingly.Because the output voltage of the rectifier circuit contains larger pulsating components. In order to reduce the pulsation component as much as possible, on the other hand, it is necessary to keep the DC component as much as possible to make the output voltage close to the ideal DC. This measure is filtering. Filtering is usually achieved by using the energy storage effect of capacitors or inductors.Figure 10. Bridge Rectifier Circuit with CapacitorIn this experimental circuit, capacitor filtering is used, that is, a filter capacitor C is connected in parallel with the load resistance RL. The circuit is shown in Figure 11, and the filtered waveform is as shown in the figure below.Figure 11. Full-wave Rectification Filter WaveformThe DC component of the full-wave rectified output voltage (compared to the half-wave) is increased, and the pulsation is reduced, but the transformer needs a center tap, which is troublesome to manufacture, and the rectifier diode needs to withstand high reverse voltage, so it is generally suitable for the low output voltage.Figure 12. Half-wave Rectification Filter WaveformHalf-wave rectification is the most commonly used circuit that uses the unidirectional conductivity of a diode for rectification. Ⅵ Difference between Bridge Rectifier and Full-wave Rectifier Circuit1) Don't need a center tap on the secondary side of the bridge rectifier circuit transformer, but use 2 more rectifier diodes.2) The full-wave rectifier circuit uses less than 2 rectifier diodes, but the secondary side of the transformer should be center-tapped.3) The reverse withstand voltage of the rectifier diode used in the full-wave rectifier circuit is twice that of the bridge rectifier.4) Rectification and full-wave rectification have different requirements for the number of secondary transformers. The former requires only 1 set of coils, while the latter requires 2 sets.5) Rectification and full-wave rectification have different requirements for the secondary current of the transformer, the former is twice the latter. Frequently Asked Questions about Bridge Rectifier Circuit1. What does a bridge rectifier do?A bridge rectifier provides full-wave rectification from a two-wire AC input, resulting in lower cost and weight as compared to a rectifier with a 3-wire input from a transformer with a center-tapped secondary winding. ... Diodes are also used in bridge topologies along with capacitors as voltage multipliers. 2. How does a bridge rectifier convert AC to DC?Bridge rectifiers convert AC to DC using its system of diodes made of a semiconductor material in either a half wave method that rectifiers one direction of the AC signal or a full wave method that rectifies both directions of the input AC. 3. What happens when a bridge rectifier fails?Without capacitor smoothing, when 1 diode fails open in a bridge rectifier, both voltage and current reduce. With capacitor smoothing, when 1 diode fails open in a bridge rectifier, the voltage remains fairly constant but the current increases. 4. Why do we use 4 diodes in bridge rectifier?The bridge rectifier consisting of four diodes enables full wave rectification without the need for a centre tapped transformer. The bridge rectifier is an electronic component that is widely used to provide full wave rectification and it is possibly the most widely used circuit for this application. 5. Why is a bridge rectifier more preferable than a full wave rectifier?Bridge rectifier is driven by a single winding which carries current both cycles in load. ... Full wave is better than bridge in one more aspect i.e. the output DC voltage is slightly higher than bridge. This is because it has only 1 diode drop from AC to DC.

IntroductionUSB is very common, because it is indispensable for data transmission and charging. In modern life, we can see one or more USB ports on desktop computers, laptops, TVs, game devices, cars, media players, phones, and other electric devices, etc. USB devices are very important for our life. Look at your computer or smart phones, we probably know what it used for, however, fewer people know the full name of USB and what the real meanings of USB protocols and USB types.USB Ports, Cables, Types, & ConnectorsCatalogIntroductionⅠ Figure USB Ports and Standards OutⅡ USB Port Colors MeaningⅢ USB-C vs Type CⅣ USB 2.0 vs USB 3.0Ⅴ According to Labels Behind USB PortsHere are some easy steps to identify USB ports with different standards.Ⅰ Figure USB Ports and Standards OutUSB (universal serial bus) aims for input and output interfaces standard. It is widely used in information transformation products such as personal computers and mobile devices. The USB interface has hot-swappable, plug-and-play functions, and can be connected to a variety of external devices, such as a mouse and keyboard, etc. Our mobile phone charging uses the USB connector. These USB devices give us great convenience. USB chargers, USB connectors, USB hub, USB ports and USB cables, are all USB the same? What is USB 2.0 and USB 3.0? Low speed, full speed, and high speed mean what? What are Type-A, Type-B, and Type-C? Here you will get a full answer.Versions of USBThe USB 1.0/2.0/3.0 we often say refers to the technical specifications. The biggest difference among them is speed, that is, they indicate the speed of USB transfer files. The maximum transmission bandwidth of USB 3.0 is up to 5.0Gbps (640MB/s). Now many high-speed U disks or hard drives of portable electric devices use USB 3.0 or USB 3.1. USB also includes the old USB 1.1 standard and  USB 2.0 standard. The traditional maximum transfer rate of USB 1.1 is 12Mbps. Generally, manufacturers call its products that comply with the USB 1.1 standard as "full-speed USB." When the high-speed USB 2.0 was first introduced, the highest transmission rate was only 240Mbps. Later, the USB Promoter Group increased the rate to 480Mbps in October 1999, which is 40 times faster than the traditional USB 1.1. USB 2.0 is backward compatible with USB 1.1. Of course, USB 1.1 devices are "upward compatible" with USB 2.0, but they cannot reach the transmission speed of USB 2.0 and automatically stay at low speed. The maximum length of the USB 2.0 cable is 5 meters, but if five USB adapters are used, the maximum length can be up to 30 meters.Although you'll still be able to connect old-school devices with USB Type-A or USB Type-B connectors, but now you have more choices, that is USB4. USB4 is a USB system specified in the USB4 specification which was released in version 1.0 on 29 August 2019 by USB Implementers Forum. It leverages the Thunderbolt 3 protocol to deliver speeds up to twice as fast as the USB version it replaces. The USB4 architecture defines a method to dynamically share a single high-speed link with multiple end device types to best serve the transfer of data by type and application. USB-A, USB-B, and USB-C Port Types-Which is faster?Type-A/B/C determines the appearance of the USB ports. For example, the mouse, keyboard, USB flash drive and other interfaces we use are generally Type-A, which is also the most widely used interface. Type-B is more common in printers, monitors and other devices. In the past, Micro USB and Mini USB commonly used in mobile phones were portable versions of USB 2.0. The appearance of Type-C is very recognizable, slimmer. Its biggest feature is flippability, that is, USB-C connector has no up or down orientation, so you never have to flip it over to plug it in.1) Type-A: Standard USB PortType-A is the most common types of USB ports on computers. It has a notable feature: direction requirements. The connector (male port) must be inserted into the interface (female port) from a certain direction, in addition, because the appearance of the two sides of the USB male port is very close, this insertion process often makes mistakes.2) Type-B: Commonly used in printer equipmentType-B is the most common and popular data interface type on printers and displays, and some displays will also use it.3) Type Micro-B: USB standard for mobile devicesCurrently, most Android phones use the Micro USB interface (USB Micro-B), which is still widely used in various mobile portable devices.4) Type-C: It will become mainstreamAlthough Type-C has just appeared, it is foreseeable that as the USB Type-C technology matures, various notebooks, tablets and even smart phones in the future will begin to use the USB Type-C interface. Ⅱ USB Port Colors MeaningColorUSB ConnectorUSB Speed StandardNoteWhiteUSB-A or USB-B  Micro USB-AUSB 1.0 or USB 1.1*BlackUSB-A or USB-B Micro USB-BUSB 2.0 Hi-Speed*BlueUSB-A or USB-BUSB 3.0 Super Speed*RedSleep-and-Charge USB-AUSB 3.1 Gen 2 USB 3.2Usually denotes an "always on" portYellowSleep-and-Charge USB-AUSB 2.0 or USB 3.0Higher power or "always on" portⅢ USB-C vsType CThe Type-C is the same as the USB C, because the USB C is also called USB Type-C. However, there are slight differences between them. Let’s look at the following facts.Features of USB-C Connector:1. Ultra-thinThe old USB port size is 14mm * 6.5mm, while the USB-C is only 8.4mm * 2.6mm.2. No OrientationLike the Lightning, there will be no problem regardless of whether it is plugged in or reversed. It claims to be able to up to 10,000 times of repeated plugging and unplugging.3. Fast Transfer RateThe maximum transfer rate of the USB-C port is 10Gb per second, which is much faster than USB 3.0.4. Two-way TransmissionUnlike the old USB port, the power can only be transmitted in one direction. The USB-C port is bidirectional, so it can have two transmission power ways. Therefore, users can not only use laptops to charge mobile devices, but also use other devices or mobile power sources to charge laptops.5. Strong Power Supply CapabilityThe standard specification cable equipped with Type-C connector can pass 3A current, and it also has a super USB power supply capacity, which can up to 100W of power.6. Backward CompatibilityUSB-C can be compatible with the old USB protocol, but users need an additional adapter.USB-C refers to the Type C port that uses the USB 3.1 standard, but it should be noted that USB-C is not equal to Type C. Because there are many Type C devices that can only reach USB 2.0 or USB 3.0 transfer rate.With the improvement of technology, Type-C also supports the USB3.1 standard. Because the voltage and current increase, the coding consumption is reduced, from 20% of USB 3.0 to 3%. In other words, users can quickly transfer data and video through Type-C, or charge faster. Also users can charge other devices with their mobile phones. As for the display, when using Type-C for data transmission, there is no need to use another power cord to power the display, which solves the problem of messy desktop cables. Even the relatively high-end HDMI and DP ports cannot do it.The USB-C connector can be expanded into three: power supply/ USB transmission/ VGA or HDMI, which is the next-generation mainstream USB interface. The type-c cable is also of great help to the arrival of the 5G. Because the port of it becomes smaller, the flattening of electronic products is promoted. And in the transmission of audio and video, the tc data line has faster speed. At present, well-known technology manufacturers such as Sony and Apple have widely used type-c cables on their electrical devices because they can support multiple formats and reduce the limitations of USB. In short, the arrival of the 5G actually wants everyone to experience faster bandwidth, so the corresponding supporting facilities should also keep up. The type-c cable is undoubtedly one of them. Ⅳ USB 2.0 vs USB 3.0Although USB has developed to the USB3.1 protocol, we often see two types of USB 2.0 and USB 3.0 on devices. How do we distinguish these two interface types in daily use? Some people will say that USB 3.0 port is blue and USB2.0 port is black, which is easy to distinguish. In fact, it is not. Even though most USB3.0 ports use blue, there are many special cases. Here are some examples. The color of the USB ports on some models does not have any special treatment, and it looks no different from USB 2.0 type, and it is all black. However, it is often marked with "SS" in front of the logo. "SS" is the abbreviation of "SuperSpeed USB", which means connector or port that uses the USB 3.0 standard. The black USB type is also suitable for USB 3.0. The USB ports in Apple's new MacBook notebooks are all USB 3.0 standard, but in order to keep in harmony with the color of the computer cover, a white connector design is adopted. The USB ports on the Razer gaming notebooks are also USB 3.0, but in order to match the bright green keyboard backlight on the body and the Razer logo, the color of the USB port adopts "green". It improves the recognition of the machine and the brand, because no third-party manufacturer has adopted a green USB interface design. In addition, distinguish the metal pins of the USB ports. Generally, USB 2.0 uses a row of 4 pins, while USB 3.0 has a two-row pin design, with 5 pins in the front row and 4 pins in the back row. In addition, there is also a hybrid port of eSATA and USB 2.0, which can plug in both USB devices and eSATA interface devices. However, they are common in business models of previous years. Ⅴ According to Labels Behind USB Ports"+" sign - It represents the USB interface with high current output capability. The ordinary USB interface provides a maximum current of 500mA, but it may not be able to drive when encountering "high energy consumption" devices such as mobile hard disks and USB optical drives. Therefore, when it appeared, the output current on this interface can reach 1000mA (1A), which greatly enhances the drive capability."SS" - It is actually a symbol of USB 3.0. If the USB port has “SS” (or “SuperSpeed”) on its label, it’s a USB 3.0 port. If it’s“SS 10”, it’s a USB 3.1 port."Lightning Logo" -It generally appears on notebooks, and the USB port with it has a power-off charging function. That is, it can use its own battery or an external power supply to charge the mobile device when it is turned off. The lightning mark with an arrow indicates the Thunderbolt 3: two-way charging and two-way data transmission. Thunderbolt 3 supports for up to 40Gbps of throughput, alongside reduced power consumption and the ability to move as much as 100 watts of power over the interface. And it also means that a single cable is all you need to push power and transfer a large amount of information (up to and including video data for two 60Hz 4K displays) to and from even a complex device like a computer, something many laptop manufacturers have been quick to take advantage of.USB is an important interface on the computer. Almost 90% of the external devices are connected by it for mobile hard drives, such as U disks, printers, etc. Understanding the above information can analyze and solve the most common problems of unrecognized external devices of USB. At the same time, it is also very useful for us to choose USB products. Ⅵ Frequently Asked Questions about USB Types and USB Versions1. What are the different types of USB ports?Types of USB Ports and ConnectorsUSB-AUSB-BUSB-B MiniUSB-B MicroUSB-CLightning 2. How can I tell the difference between USB 2.0 and 3.0 ports?You can generally tell the difference between USB 1.0, 2.0, and 3.0 by color alone. While the size and shape may be identical, the key is to look at the color of the plastic inside the device. The USB 1.0 features a white plastic color, while USB 2.0 is black, and the USB 3.0 is blue. 3. What is the difference between USB Type A and C?The USB-A has a much larger physical connector than the Type C, Type C is around the same size as a micro-USB connector. ... The beauty of Type C is that it can be inserted any way up as the connector pins are the same on either side. 4. Are USB 2.0 and 3.0 ports the same?The A connectors still work properly so any 2.0 device with a 2.0 cable can be used with 3.0 ports or hubs. To sum up: USB 3.0 devices require 3.0 cables. ... USB 2.0 cables can be used with 3.0 ports but the transfer rate will fall back to 2.0. 5. Why is my USB 3.0 port not working?Update to the Latest BIOS, or Check USB 3.0 is Enabled in BIOS. In many cases, your motherboard will be responsible for software issues related to your USB 3.0 ports or any other ports on the motherboard. For this reason, updating to the latest BIOS may fix things.

IntroductionAs everyone knows, Error correction code memory (ECC memory) is a type of computer data storage technique. It identifies and fixes the most common errors which could otherwise lead to data corruption or system crashes. In other words, it is one of the most important techs for this loss and system errors prevention. There will be people who have such a question: now the memory technology is improved greatly, it’s possible to use ECC server RAM inside of your regular desktop computer at home, but is it something you SHOULD do? This note will help you find clues step by step.ECC Memory ExplainedCatalogIntroductionⅠ What Causes Errors in RAM?Ⅱ Is ECC RAM Better?Ⅲ ECC Server RAM or Regular Home Desktop?Ⅰ What Causes Errors in RAM?The ram error is caused by electromagnetic interference inside the computer. This interference will cause the units of DRAM (Dynamic Random Access Memory) to spontaneously change to the opposite state. Unit errors may be hidden, that is, they will not have a serious impact on the data. However, the memory units are interrelated, so unit changes may affect the entire operating system, resulting in system errors, especially when the strict operation is required. To be specific, memory errors will cause security vulnerabilities, crashes, transcription errors, lost transactions and corrupted or lost data, and one of the most common types of memory error is a single-bit error.Ⅱ Is ECC RAM Better?In the face of these problems, if memory can fix the error itself, what will it look like? That is ECC RAM.Memory Chips DifferenceECC RAM is server memory. This type of memory module has an ECC error check storage chip (the number of storage chips is an odd number). The application of ECC can ensure that the server is safer and more stable during operation. However, the number of chips stored in ordinary memory sticks is even. In reality, ECC RAM has 9 memory chips instead of 8. Error Checking and CorrectingThe ECC memory is equipped with ECC error-checking technology. After error checking and correction, the stability and reliability of the server system can be effectively guaranteed. For ordinary ram, when the word detects an error, the error location cannot be determined, and the error cannot be corrected. Therefore, for a single task that takes a long time and cannot be suspended or error, ECC memory is an inevitable choice. However, ordinary PCs will not use because of high-cost price. Application DifferenceBecause ECC memory can effectively store and maintain data integrity and is equipped with check and correction technology, ECC memory further reduces data corruption. Therefore, it is mostly used in servers and graphics workstations such in financial and scientific industries. Non-ECC memory sticks are more suitable for the general public's use. Capacitor DifferenceAs server memory applications require higher capacity, ECC memory modules usually start at 4GB, while ordinary memory modules usually start at 2GB. The standard configuration on home computers is 4~8GB of memory. Price DifferenceDue to the higher-tech of ECC memory sticks, their capacity is also larger than ordinary memory. Therefore, ECC memory sticks are more expensive than ordinary memory.Ⅲ ECC Server RAM or Regular Home Desktop?ECC memory is usually used in servers or graphics workstations. Because of the check and correction function, when there are some read and write errors in the memory, the ECC RAM can correct these errors and reduce the probability of downtime/blue screen. Guaranteed data storage and accuracy of reading and writing.Server memory and ordinary PC memory are very similar, there is no obvious difference in appearance and structure, but its price is higher than ordinary memory. There are three main types of server memory: SDRAM, DDR, and DDR2. At present, server memory is mostly used by DDR and DDR2. As time goes by, the server uses some new technologies now, such as ECC, chip kill, register, hot-swap technology, FB-DIMM (full buffer memory module), etc. More server memory currently adopts ECC and REG ECC technologies. The chips on REG ECC memory are generally 2-3 more than ordinary motherboards, mainly PLL (phase-locked loop) and Register IC. ECC and ECC REG memory have been developed for a period, and the frequency mainly has 133, 266, 333, 400, 533, and 667 stages. What is RECC? The specific uses of RECC memory are as follows: phase-locked loop chip, the bottom of the memory stick are smaller than Register ICs. Generally, there is only one, which can adjust the clock signal and ensure signal synchronization between the memory modules. The smaller IC chip (2-3 pieces) at the bottom plays a role in improving the driving capability. Server products need to support large-capacity memory. The motherboard alone cannot drive such a large-capacity memory. Instead, the memory module with Register is used to improve the driving ability, so that the server can support up to 32GB of memory. Because of the PLL and Register chips, the server memory capacitor can be made very large, it can better meet the endless requirements of the ever-increasing software for memory. Therefore, it is recommended that the server whose requirement is over 16G use RECC RAM.RECC has one more register. We can understand the function of the memory as a book directory. When the memory receives a read and write command, it will retrieve this directory first, and then perform read and write operations, which will greatly improve the efficiency of the server memory. So some people mistakenly think that RECC RAM runs slower than ECC RAM. The Register memory that can be used at present also has an ECC function, and some motherboards require the memory to support Register. In fact, all registered memory is ECC memory. The use of ECC memory requires the support of other computer components, such as the motherboard and cpu, and may also need to be set in the BIOS before it can be used on most server CPUs and motherboards (some non-server CPUs and motherboards also support). In addition, when purchasing ecc memory, you need to pay attention to whether it is ecc udimm or ecc rdimm or ecc lrdimm or ecc 3ds rdimm or something else. Because your computer configuration may not support some types.What’s more, all of the modern, contemporary storage drives use ECC at some level internally. HDD, SSDs. The data densities of the HDD push the edge where need to keep up with track integrity. NAND in SSDs tend to loose data bits in usage over time. The SSD controller in the T2 isn't remarkable on the ECC dimension. All the ones that store the data encrypted 'at rest' basically have to if going to be competently implemented. In addition, ECC generally works on all Ryzen Chips minus the APUs (with the exception of the pro apus), they tend to not be on the QVL since it costs time and money to do that. Frequently Asked Questions about ECC Server Memory1. What is ECC memory?Error correction codeError correction code (ECC) memory is a type of RAM memory found in workstations and servers. It's valued by professionals and businesses with critical data for its ability to automatically detect and correct memory errors, thus fighting data corruption. 2. Which is better ECC or non-ECC memory?Non-ECC (also called non-parity) modules do not have this error-detecting feature. ... Using ECC decreases your computer's performance by about 2 percent. Current technology DRAM is very stable, and memory errors are rare, so unless you have a need for ECC, you are better served with non-parity (non-ECC) memory. 3. How does ECC memory work?ECC memory uses the extra bits to store an encrypted code when writing data to memory, and the ECC code is stored at the same time. ... As data is processed, ECC memory is constantly scanning code with a special algorithm to detect and correct single-bit memory errors. 4. What is the benefit of ECC memory?ECC memory protects your system from potential crashes and inadvertent changes in data by automatically correcting data errors. This is achieved with the addition of a ninth computer chip on the RAM board, which acts as an error check and correction for the other eight chips. 5. Who needs ECC RAM?Error-correcting code memory (ECC memory) is a type of computer data storage that can detect and correct the most common kinds of internal data corruption. ECC memory is used in most computers where data corruption cannot be tolerated under any circumstances, such as for scientific or financial computing.

IntroductionFor people who have been in touch with digital circuits or analog circuits, the 555 IC is definitely classic work. With its low cost and reliable performance, it is widely used in various electrical appliances, including instruments and meters, household appliances, electric toys, and automatic control. The 555 timer only needs a few external resistors and capacitors to realize pulse generation and conversion circuits, such as multiple oscillators, monostable triggers and schmitt triggers. So how does it work in the circuit? What the role of its circuit? Here gives several typical 555 circuit examples for specific analysis.555 Timers Circuit LearningCatalogIntroductionⅠ Basic 555 Timer Circuit AnalysisⅡ 555 Multivibrator Circuit AnalysisⅢ 555 Timer Monostable Flip Flop Circuit AnalysisⅣ Classic 555 Timer Circuits DiagramsⅤ 555 Timer IC ModesⅠ Basic 555 Timer Circuit Analysis555 Means What?555 timer is a convenient and powerful IC, which is widely used in signal generation, conversion, control and detection. The origin of this name, because it is divided by three 5KΩ resistors. The 555 timer is a simple integrated circuit that can be used to make many different electronic circuits. With the following circuits analysis you will know how 555 IC works.Figure 1. Basic 555 Timer Circuit✔️ Circuit AnalysisR is not the reset terminal, when set to 0, Q is 0,  is 1, Uo outputs 0, and is 1 added to the base of the transistor T, the transistor is in the conducting state.① When R=0, Q=1, uo=0, T is saturated and turned on.② When R=1 (there is no reset function at this time):UTH>2VCC/3, UTR>VCC/3, C1=0, C2=1, Q=1 or =0, uo=0, T is saturated and turned on. (Analysis: C1's positive input terminal is 2VCC/3, C1's negative input UTH terminal is greater than the positive input terminal, working in saturation, and output 0. C2's negative input terminal is 1VCC/3, which is smaller than the positive input Terminal UTH, and outputs 1. There is a horizontal line above RD and SD, which means low level, meaning is Reset. C1 outputs 0, RD is valid, then Q is 0, not 1, Uo outputs 0, and is not acting on the base of the triode.)③ When R=1, UTH<2VCC/3, UTR>VCC/3, C1=1, C2=1, Q and remain unchanged, uo and T remain unchanged. (Analysis is the same as above)④ When R=1, UTH＜2VCC/3, UTR＜VCC/3, C1=1, C2=0, Q=0, =1, uo=1, T is cut off. (Analysis is the same as above) Learn how the inputs interact with the supply voltage to trigger and reset the output high and low. Find out which pins can be used to adjust the threshold at which that change happens.Ⅱ 555 Multivibrator Circuit AnalysisFigure 2. 555 Multivibrator Circuit Analysis Figure 3. 555 Multivibrator Circuit Example✔️ Circuit Analysis First, the power supply VCC charges the capacitor C through R1 and R2, and the voltage of the capacitor must be relatively small, less than 1VCC/3. Similarly, the positive terminal of C1 is 2VCC/3, the negative terminal of C2 is 1VCC/3, and the TH and TR terminals are connected At the same time, it is less than 1VCC/3 at the beginning. At this time, C1 outputs 1, C2 outputs 0, and the set terminal is valid (with detailed confirmation): Q is 1, is not 0, and uo is 1, the transistor is cut off, and outputs high level. At this time, the power supply is still charging the capacitor. When the TH and TR terminals are connected together, the voltage is less than 2VCC/3 and greater than 1VCC/3; C1 outputs 1, C2 outputs 1, the transistor is cut off, and uo is 1. When the capacitor is greater than 2VCC/3, C1 outputs 0 and C2 outputs 1. At this time, Q is 0, is not 1, uo is 0, the output is low, and the transistor is turned on. The capacitor will be discharged through pin 7. After this, the voltage at the point where TH and TR connected will gradually decrease, less than 2VCC/3 and greater than 1VCC/3, and then it will be less than 1VCC/3, to form a harmonic oscillator.The pulse width tp1 of the first transient state, that is, the time required for uc to rise from VCC/3 charging to 2VCC/3 (charged through two resistors):The second transient state pulse width tp2, that is, the time required for uc to discharge from 2VCC/3 to VCC/3:Duty cycle: the time that the high level occupies the entire cycle., it can be seen that its duty cycle is always greater than 50%.Examples 1Circuit with Adjustable Duty Cycle (add an adjustable resistor)Figure 4. Circuit with Adjustable Duty Cycle (add an adjustable resistor)It can be calculated:Where T1=0.7R1C (T1 is charging time), T2=0.7R2C (T2 is discharging time)Total time T=T1+T2=0.7(R1+R2)CSo R1, R2, and C are determined, and the period T is also determined.Duty Cycle Calculation Example 2Circuit with Adjustable Duty Cycle (1KHz)Figure 5. Circuit with Adjustable Duty Cycle (1KHz)✔️ Circuit AnalysisT = 0.7(R1+R2)C, f = 1/T, the duty cycle circuit only needs to adjust the resistance value. Ⅲ 555 Timer Monostable Flip Flop Circuit AnalysisWorking Characteristics① It has two different working states: steady state and transient state.② Under the action of an external trigger pulse, it can switch from the steady state to the transient state. After the transient state is maintained for a period of time, the circuit can automatically return to the steady state.③ The transient state cannot be maintained for a long time, and the duration of its sustaining time depends on the parameters of the circuit itself and has nothing to do with the trigger pulse. So what is the principle of a monostable circuit?Figure 6. 555 Timer Monostable Circuit Analysis Figure 7. 555 Timer Monostable Circuit Example✔️ Circuit AnalysisFirst, the TR terminal is at a high level ui, which must be greater than 1VCC/3. At this time, C2 outputs 1, and the power supply charges capacitor C through R. The charging voltage is less than 1VCC/3 (TH), CO voltage is equal to 2VCC/3, C1 outputs 1, and it is in the holding state at this time. Assuming that the non-reset terminal of R is reset before power on, the output of uo is 0, and then the previous state is still maintained and the output is 0 at this time. is 1, the transistor is turned on, the capacitor is discharged through pin 7, and uc is zero level. At a certain moment, ui is low, C1 still outputs 1, C2 outputs 0, Q is 1, is 0, uo outputs 1 (high level), and the transistor has been in the cut-off state. At this time, VCC can charge the capacitor (uc is getting larger). When uc is between 1VCC/3~2VCC/3, assuming that the TR terminal returns to the original state (high level), C1 outputs 1 , C2 outputs 1, at this time uo keeps in original state, it is still 1, and the transistor is in the cut-off state. When uc is greater than 2VCC/3, C2 is still 1, C1 output is 0, Q is 0, is 1, and uo is 0, the transistor is turned on and in a discharging state, at this time, uc is getting smaller and smaller.Summery:1. As long as a low-level trigger signal is given, the temporary stable stay time is the charging time of voltage 0V~ 2Ucc/3 (the time represented by tp).2. Charging time Tp=1.1RC3. It can be used as a timing circuit, and the time can be determined by RC.Example: Timing Circuit Design (1s delay time)Figure 8. 555 Timer Delay Circuit ExampleⅣ Classic 555 Timer Circuits DiagramsThere are A LOT of projects out there using the 555 in various ways and it’s easy to find schematics to make a project that has already been proven. Here lists some typical projects using 555 timer in circuits. Let’s have a look. 🔺 Car Tachometer🔺 SIREN🔺 Flashing Lights🔺 Knight Rider Circuit🔺 Laser Ray🔺 Latch🔺 LED Dimmer🔺 555 Amplifier🔺 Light Detector🔺 Machine Gun🔺 Metal Detector🔺 Motor PWM🔺 Music Box🔺 Zener Diode Tester Ⅴ 555 Timer IC Modes555 timer will use different models in different circuits to meet circuit requirements. Therefore, it has many derivative models produced by different companies with different pin functions, and uses CMOS design. What;s more, some chips include several integrated 555 timers. Some common models of the 555 chip family are as follows:ManufacturerModelRemarksCustom Silicon SolutionsCSS555/CSS555CCMOS chip, minimum working voltage 1.2V, IDD < 5µACEMIULY7855*ECG SemiconductorsECG955MTimer Single Rc-type OscillatorExarXR-555Highly stable controllerFairchildNE555/KA555Time-delay or mono-stableHarrisHA555*IK SemiconILC555CMOS chip, minimum working voltage 2VTexas InstrumentsSE555/NE555*RenesasICM7555CMOS RC timersLithic SystemsLC555Available in Industry's Smallest 8-Bump DSBGAMaximICM7555CMOS RC timers, minimum working voltage 2VMotorolaMC1455/MC1555Monolithic timerNational SemiconductorLM1455/LM555/LM555C*National SemiconductorLMC555CMOS chip, minimum working voltage 1.5VNTE SylvaniaNTE955MAccurate time delaysRaytheonRM555/RC555*RCACA555/CA555C*STMicroelectronicsNE555N/ K3T647*Texas InstrumentsSN52555/SN72555*Texas InstrumentsTLC555CMOS chip, minimum working voltage 2VZetexZSCT1555Precision single cell timerNXPICM7555CMOSHitachi SemiconductorHA17555Accurate time delays or oscillations Frequently Asked Questions about 555 Timer Circuit1. What does a 555 timer do in a circuit?The 555 timer IC is a very cheap, popular and useful precision timing device which can act as either a simple timer to generate single pulses or long time delays, or as a relaxation oscillator producing a string of stabilised waveforms of varying duty cycles from 50 to 100%. 2. How much voltage can a 555 timer take?The standard TTL 555 can operate from a supply voltage between 4.5 volts and 18 volts, with its output voltage approximately 2 volts lower than its supply voltage VCC. The 555 can source or sink a maximum output current of 200mA, (but it may get hot at this level), so the circuit variations are unlimited. 3. What are the modes of operation of a timer?The timer registers can be used in two modes. These modes areTimer mode and the Counter mode. The only difference between these two modes is the source for incrementing the timer registers. 4. What are the basic operation modes of the 555 timer?The operating modes of a 555 timer are astable, bistable and monostable. Each mode of operation signifies with a circuit diagram and its output. 5. What is the maximum frequency of a 555 timer?2MHzaccording to the website, the 555 timer has a maximum frequency of 2MHz.

IntroductionAs everyone knows, in order to create a passive low pass filter, combing resistive elements with reactive elements happens often. Put simply, a typical circuit composed of resistors and capacitors or inductors. According to theories, the resistor–inductor (RL) low-pass topology is equivalent to the resistor-capacitor (RC) low-pass topology in terms of filtering capability. However. in fact, RC low pass filters are more common, so this article will focus on first-order RC low pass filters.In this video, Passive RC Low Pass Filter has been discussed. CatalogIntroductionⅠ Typical RC Circuit1.1 Time Domain1.2 Frequency DomainⅡ First-order Low Pass Filter on Software2.1 Basic Filtering Algorithm2.2 Basic Algorithm of First-order RC Digital FilteringⅢ Optimization Method- Filtering Coefficients AdjustmentⅠ Typical RC CircuitThe RC circuit has thousands of uses and is a very important circuit to study. Not only can it be used to time circuits, it can also be used to filter out unwanted frequencies in a circuit and used in power supplies, like the one for your computer, to help turn ac voltage to dc voltage.Figure 1. Typical RC Circuit (DC, AC, and Pulse Signals can all use it)1.1 Time DomainCapacitor Current:According to Kirchhoff’s Voltage Law:Where, the unit of Ui is volts, the unit of RC is seconds, and τ=RC, get:Suppose the initial voltage of the capacitor is 0, where:R=1000ΩC=4.7uFUi=1Vt=0.0001~0.1sτ=RCVc(τ)=0.632 Figure 2. Step Response Curve of a First-order RC System1.2 Frequency DomainTaking the capacitor voltage as the output, the network function of the circuit is:Where u1=Ui, u2=UoLet ωc be equal to:, which is the cut-off frequency.Amplitude and phase angle function:Value of variables:R=1000ΩC=4.7uF |A(fc)|=0.707θ(fc)=-45, f=0.001, 1, …….100000.Amplitude and phase frequency characteristics:Figure 3.Figure 4.Logarithmic representation of amplitude-frequency characteristic:Figure 5.Analysis:When ω<ωc, the amplitude is a straight line parallel to the coordinate, and there is no attenuation.　When ω>ωc, it is a straight line whose slope is proportional to -20dB/decade.When ω=ωc, the gain is attenuated to 0.707, which is -3dB, and the phase lags by 45 degrees, corresponding to a low-pass filter. This frequency is usually called the cutoff frequency. Disadvantages:When using this analog filter to suppress low-frequency interference, the filter is required to have a larger time constant and a high-precision RC network. Increasing the time constant requires increasing the value of R, and meanwhile, the leakage current increases accordingly, thereby reducing the filtering effect.Figure 6. RC CircuitⅡ First-order Low Pass Filter on SoftwareAdvantages1) The use of digital filtering algorithms to achieve dynamic RC filtering can well overcome the shortcomings of analog filters.2) This kind of algorithm is more practical when the simulation constant is required.3) It has a good inhibitory effect on periodic interference.4) Save RAM space Disadvantages1) Exit phase lag, resulting in low sensitivity.2) It cannot filter out interference with a frequency higher than half of the sampling frequency (called the Nyquist frequency. For example, if the sampling frequency is 100 Hz, it cannot filter out interference signals above 50Hz). In this case, an analog filter should be used.3) For the single-chip microcomputer without multiplication and division running instructions, the workload of the program operation is relatively large.2.1 Basic Filtering AlgorithmOrigin of the AlgorithmThe transfer function of the first-order RC low-pass filter in the S domain for frequency analysis:Through z-transformation (there are many methods, such as first-order forward difference, bilinear transformation, etc. Here, the first-order backward difference method is used): Into the S-domain Transfer Function After the derivation is transformed into the difference equation, we can get:The transfer function in the S domain can be transformed into a difference equation in the time domain through the Z transformation.2.2 Basic Algorithm of First-order RC Digital FilteringX is the input, Y is the output value after filtering, then: a is a parameter related to the RC value, called the filter coefficient, its value determines the weight of the new sample value in the filtering result of this time, and its value is usually far less than 1, when the sampling interval t is small enough:1) The smaller the filtering coefficient, the smoother the filtering result, but the lower the sensitivity.2) The larger the filtering coefficient, the higher the sensitivity, but the more unstable the filtering result.3) The output value this time mainly depends on the last filtered output value, and the current sampled value has a relatively small effect on this output, which plays a corrective role.4) Cutoff frequencyFor example: t=0.5s (f=2Hz), a=1/32where fl=(1/32)/(2*3.14*0.5)=0.01Hz Basic ProgramWrite the program according to the basic principles and formulas of first-order filter, as follows:/*In the program, integer arithmetic is faster than decimal arithmetic. In order to speed up the processing speed of the program, for calculation convenience, a is an integer (from 0~255), 1-a is replaced by 256-a, which means that the new sample value is being filtered. The weight in the result (you can also change the base of 1-a to 100-a, and the calculation result will be processed accordingly)*/#define a 128 char value; //Last filtering valuechar filter(){    char new_value;    new_value=get_ad();//Sampling value    return(256-a)*value/256+a*new_value/256；}Initial Optimization of the ProgramReduce the number of operations of multiplication and division to increase the speed of operations.Specific optimization methods:First compare the new sampled value with the previous filtering result, and then use different formula calculations based on the comparison, so that the calculation efficiency of the program is doubled.Resolve the basic formula to get: ProcessNotes:S → New Sampling ValueR → Previous Filtering ResultC→ Filter CoefficientN→ New Filtering Result Program/*Int: NEW_DATA     New sampling values       OLD_DATA       Last filtering result       k        Filter coefficient (0~255)  Out:         The filtering results */ char filter_1(char NEW_DATA,char OLD_DATA,char k){    int result;    if(NEW_DATA<OLD_DATA)    {        result=OLD_DATA-NEW_DATA;        result=result*k;        result=result+128;//+128 Round Up        result=result/256;        result=OLD_DATA-result;    }    else if(NEW_DATA>OLD_DATA)    {        result=NEW_DATA-OLD_DATA;        result=result*k;        result=result+128;//+128 Round Up        result=result/256;        result=OLD_DATA-result;    }    else result=OLD_DATA;    return((char)result);} Filtering AnalysisWhen the filtering coefficient is 30:Figure 7.When the filtering coefficient is 128:Figure 8.When the filtering coefficient is 200:Figure 9.It can be seen that the smaller the filtering coefficient, the smoother the filtering result, but the lower the sensitivity. On the contrary, the larger the filtering coefficient, the higher the sensitivity, but the more unstable the filtering result.Insufficient1) The contradiction between sensitivity and smoothness2) Errors caused by discarding decimals.For example: the current sampling value=25, the last filtering result=24, and the filtering coefficient=10;According to the algorithm, the filtering result of this time = 24.0390625In single-chip microcomputers, floating-point numbers are rarely used, and the fractional part is either discarded or needs to round up. In this way, the result is 24. If the sampling value is always 25, the result will always be 24. Because the filtering result and the actual data will always have an error that cannot be eliminated. Sometimes it will cause the filtering result curve to deviate from the actual value when the sampling data is stable at a certain value (that is, there is a large error between the filtering result and the actual result although in a stable case). Be Careful1) Changing the filtering coefficient, increasing it will reduce the smoothness, and if it is too large, the filtering will lose its meaning.2) The use of decimal part in calculations will bring heavy computational pressure to the CPU. Ⅲ Optimization Method- Filtering Coefficients AdjustmentRealize the Function1) When the data changes rapidly, the filtering results can be followed up in time, and the faster the data changes, the higher the sensitivity should be (sensitivity priority principle).2) When the data becomes stable and oscillates within a range, the filtering result can become stable (the principle of stability first).3) When the data is stable, the filtering result can be approximated and finally equal to the sampling data (eliminate the error caused by decimals in the calculation). Judgment before Adjustment1) Whether the data changes consistently. For example, when the two consecutive sampling values are larger than the previous filtering result, it is normal, otherwise it is regarded as inconsistent.2) Whether the data changes quickly, which is to judge the difference between the sampling value and the previous filtering result.Adjustment Principle1) When the two data changes are inconsistent, it means there is jitter. Clear the filtering coefficient to zero, and delete the new sampling value.2) When the data changes consistently, gradually increase the filtering coefficient to provide the weight of this sampling.3) When the data changes quickly (difference value> debounce count acceleration response threshold), the filtering coefficient should be increased quickly. Adjusting Filter Coefficient Process① Calculate the difference (absolute value) between the current sampling value and the last filtering result; Set the data change direction flag.② Two changes in the same direction?③ First order filter coefficient + coefficient increment (the maximum value is taken when the result is greater than the maximum value). Several Constant Parameters and Their Ranges1. Debounce counting acceleration response threshold is determined according to the actual situation.2. The maximum value of debounce count, which is generally 10.3. The increment of filtering coefficient range is 10~30.4. The maximum value of the filtering coefficient is generally 255.Before starting the first-order filtering program, open the adjustment filter coefficient program to adjust the coefficients in real time. Filtering Effect1. When the sampled data is accidentally interfered, the interference in the filtering result is completely filtered out.2. When the data oscillates within a range, the filtering result curve is very smooth, almost a straight line.3. When the sampling data has real changes, the filtering results can be followed up in a relatively timely manner.4. When the sampling data becomes stable, the filtering result gradually approaches and is finally equal to it.Finally, improve the algorithm. Taking into account the requirements of sensitivity and stability; and meanwhile, it does not consume too much RAM space. As long as a few constants are adjusted reasonably, the algorithm is more suitable for practical applications. Frequently Asked Questions about RC Low Pass Filter1. What is RC low pass filter?A low pass filter is a filter which passes low-frequency signals and blocks, or impedes, high-frequency signals. ... Low pass filters can be constructed using resistors with either capacitors or inductors. A low pass filter composed of a resistor and a capacitor is called a low pass RC filter. 2. Why RC circuit is low pass filter?Then by carefully selecting the correct resistor-capacitor combination, we can create a RC circuit that allows a range of frequencies below a certain value to pass through the circuit unaffected while any frequencies applied to the circuit above this cut-off point to be attenuated, creating what is commonly called a rc low pass fiter. 3. What is difference between RC low pass filter and RC high pass filter?Low pass filter is the type of frequency domain filter that is used for smoothing the image. It attenuates the high frequency components and preserves the low frequency components. High pass filter: ... It attenuates the low frequency components and preserves the high frequency components. 4. What is the transfer function of a low pass filter?Low Pass Filters and their Transfer FunctionsAs its name implies, a low pass filter is an electronic device that allows low frequency AC signals to pass a current through the filter circuit. The output from the filter circuit will be attenuated, depending on the frequency of the input signal. 5. How is low pass filter frequency calculated?The cut-off frequency or -3dB point, can be found using the standard formula, ƒc = 1/(2πRC). The phase angle of the output signal at ƒc and is -45o for a Low Pass Filter.

IntroductionThe modern automobile industry is developing very rapidly. Take car keys for example, the traditional mechanical keys are basically replaced now. Because our remote control keys and even smart keys are already very common. However, this also brings some troubles to many consumers-what should I do if the key is out of power or the battery is damaged? How to replace the battery? What type of battery should I choose?For example, in most cases, temperatures too high or too low still compromise their ability to store and release energy. Put simply, cold weather will decrease the lifespan of your battery because it will require charging more often. Here will give you some basic ideas of car key batteries comparison in modern life.CatalogIntroductionⅠ What Are CR Batteries?1.1 CR×××× Definition1.2 CR Button Battery ExamplesⅡ SummeryⅠ What Are CR Batteries?1.1 CR×××× DefinitionGenerally speaking, the batteries of car keys are button batteries, which have a relatively long service life. Conventionally, a battery can be used for more than 3 years. To replace the battery of the car key, you must buy the right model. Not all car keys use CR2032, while CR2450, CR2025, and CR2016 are also optional. Here, what models are CR2032 and CR2025? What does CR stand for in battery? According to IEC rules, in Lithium batteries, Chromium is also used in it that is why it's also called CR batteries. Most of the people related CR with the button or coin batteries but it's a chemical designation of Chromium.C-denotes Lithium Manganese Dioxide.R-after another letter denotes a round cell with the chemistry shown by the first letter.Digit-The next four digits indicate the size, the first two digits indicate the diameter, and the last two digits indicate the thickness.All the batteries who have this chemical substance in their batteries they can use this abbreviation CR.1.2 CR Button Battery Examples🚩CR2032 BatteryMax Size: 20.0×3.2mmNominal Capacity: 240mAhNominal Voltage: 3.0VOperating Temperature: -20°C ~+60°CRef.Weight: 3.0gCR2032 batteries is the most common battery coin providing long-lasting, reliable power for various devices. They are used to power small electronics devices such as calculators, wrist watches, various medical devices, fitness appliances, toys etc. As for CR2032 run time, that is, how long should a 2032 battery last? For example, a typical LED uses about 20mA and the capacity of a CR2032 Coin Cell is 200mAh. 🚩CR2016 BatteryMax Size: 20.0×1.6mmNominal Capacity: 90mAhNominal Voltage: 3.0VStandard Current: 0.1mAMax Continuous Current: 1.0mAMax Pulse Current: 15mARef.Weight: 1.8gCR2016 batteries are commonly used in calculators, digital watches, memory back-up, laser pens, car key remotes, calculator, toys, fitness appliances and medical devices like a clinical thermometer and a tensiometer. It has a proven track record for appliances where conventional batteries cannot be used. 🚩CR2025 BatteryMax Size: 20.0×2.5mmNominal Capacity: 170mAhNominal Voltage: 3.0VMax Continuous Current: 2.0mAMax Pulse Current: 20mARef.Weight: 2.5gCR2025 batteries provide long-lasting reliable power in various devices. This battery is frequently used in car key remotes, medical devices, digital watches, fitness devices and other electronics. 🚩CR1632 BatteryMax Size: 16.0×3.2mmNominal Capacity: 120mAhNominal Voltage: 3.0VMax Continuous Current: 1.0mAMax Pulse Current: 15mARef.Weight: 1.8gCR1632 batteries mainly used for low power consumption electronic products, generally its output current from 0.001mA to 5mA. For example, CR1632 batteries are often used in car key remotes, watches, toys and other electronic appliances. Also it provides long-lasting reliable power. Store in room temperature, ventilated, dry environment (humidity not more than 60%), having period of validity up to 2 years. 🚩CR2450 BatteryMax Size: 24.0×5.0mmNominal Capacity: 520mAhNominal Voltage: 3.0VOperating Temperature: -30°C ~+60°CMax Continuous Current: 3.0mAMax Pulse Current: 20mARef.Weight: 5.8gVery high weight-to-power ratioNo mercury addedHigh leak protectionCR2450 batteries have certain accomplishments for applications where traditions where traditional cannot be used. Use them for calculators, digital watches, laser pens, car keys, medical devices like a clinical thermometer and a tensionmeter and fitness appliances. Store in room temperature, ventilated, dry environment (humidity not more than 60%), having period of validity up to 3-5 years.🚩Recommended Readingcr2025 vs cr2032cr2016 vs cr2032Ⅱ SummeryThey are not rechargeable, and are all lithium primary batteries. That is, they are very similar to each other. The shelf life of lithium coin cells stored at normal room temperature and relative humidity is 10 years. If the manufacturing level is not high or the quality control is not good, their life will be greatly shortened. What’s more, if the use environment is ideal, their life span can reach 10 years or more. They are often used on computer motherboard CMOS batteries, memory functions or power-off protection modules, electronic scales, calculators, electronic dictionaries and other products, and can also be used on car remote control keys. With the requirements of new industries, there are also specially improved with very different capacities, mainly to improve their high-current output capabilities, such as those used in flashing lights or RF products.From the above, we can see the difference between them. As for interchangeable batteries, if you are a consumer, replace the battery with the same one that was originally intended, as the holder was designed to fit either one or the other.A derivative problem, what happens to old lithium batteries? Since they cannot be recharged, they has to be disposed of properly. For proper disposal of large numbers of lithium batteries at the same time, they can be disposed of by scattering them in different directions so that they will not touch one another. In short, you can't throw away lithium-ion batteries with your regular trash or even in your blue recycling bin. What you should do is dropping them off at a battery recycling center or battery drop-off, or requesting a battery pick-up through your local government's website. Frequently Asked Questions about Difference between Cr2032 and CR2025, CR2016, CR24501. Can I replace a CR2016 battery with a CR2032?They are not the same in thickness, the cr2016 is thinner then the cr2032 although if you stack two of the cr2016 batteries then it will then be the same thickness as the cr2032 battery and they both worked for the car stereo remote and key fob. That is, if it fits in the device's battery slot and makes a good electrical connection, a CR2016 can substitute for a CR2032. However, it will have less than half the CR2032's lifetime. 2. Can I use a CR2032 in place of a CR2025?2032 and 2025 are literally the dimensions of the battery. For as long as either fits in the battery compartment, the CR2025 and CR2032 may be used interchangeably with minimal effect although the CR2032 would probably last slightly longer simply because it has a higher capacity (mAh). 3. Are CR1632 and CR2032 interchangeable?The CR1632 battery is very similar to CR2032 or CR2025 but they are not interchangeable because of their dimensions. The name CR1632 indicates that the battery is 16mm wide and 3.2mm thick. It is rated for 3V and 130mAh capacity. 4. Is CR2450 the same as CR2032?CR2450 vs CR2032CR2450 is often compared with a very popular lithium 3.0 volts CR2032 battery. Output voltages of these batteries are the same for the same chemistry types. However, due to the larger volume of CR2450, it features a larger capacity - 600-620 mAh (CR2450) vs 210-230 mAh (CR2032). 5. What battery is equivalent to CR2032?