Schottky diode is a kind of semiconductor device with low power consumption, high current and ultra-high speed. Its reverse recovery time can be as short as a few nanoseconds, the forward conduction voltage drop is only about 0.4v, and the rectified current can reach several thousand amps.For these reasons, I think pcb instant quote The situation is still optimistic, and the market is still in a blue ocean stage. https://www.xinyun-ic.com/

　　Schottky diode is a metal-semiconductor device made of noble metal (gold, silver, aluminum, platinum, etc.) A as the positive electrode and N-type semiconductor B as the negative electrode, and the barrier formed on the contact surface between them has rectification characteristics. Because there are a lot of electrons in N-type semiconductors and only a few free electrons in precious metals, electrons diffuse from B with high concentration to A with low concentration. Obviously, there are no holes in metal A, so there is no diffusion movement of holes from A to B. With the continuous diffusion of electrons from B to A, the electron concentration on the surface of B gradually decreases, and the surface electrical neutrality is destroyed, so a potential barrier is formed, and its electric field direction is B ★ A. However, under the action of this electric field, the electrons in A will also drift from A to B, thus weakening the electric field formed by diffusion movement. When a space charge region with a certain width is established, the electron drift motion caused by electric field and the electron diffusion motion caused by different concentrations reach a relative balance, and a Schottky barrier is formed.

　　SR5100.jpg

　　Schottky barrier diode (SBD) has the advantages of high switching frequency and low forward voltage, but its reverse breakdown voltage is relatively low, mostly not higher than 60V, and the highest is only about 100V, which limits its application range. For example, in switching power supply (SMPS) and power factor correction (PFC) circuits, freewheeling diodes of power switching devices, high-frequency rectifier diodes of more than 100V for transformer secondary, high-speed diodes of 600V~1.2kV in RCD buffer circuits, and 600V diodes for PFC boost, only fast recovery epitaxial diodes (FRED) and ultra-fast recovery diodes (UFRD) are used. At present, the reverse recovery time Trr of UFRD is also above 20ns, which can not meet the needs of SMPS with 1MHz~3MHz in fields such as space station. Even for SMPS with hard switch of 100kHz, due to the high conduction loss and switching loss of UFRD and high shell temperature, a large radiator is needed, which increases the size and weight of SMPS, which is not in line with the development trend of miniaturization and thinness. Therefore, the development of high voltage SBD above 100V has always been a research topic and a hot spot of concern. In recent years, SBD has made a breakthrough, with 150V and 200V high-voltage SBD on the market, and more than 1kV SBD made of new materials has also been successfully developed, thus injecting new vitality into its application.

　　First, look at the symbol mark. Generally, the symbol of the diode is marked on the surface of the Schottky diode, with the positive electrode indicated by the triangular arrow symbol and the other end as the negative electrode.Before that, pcb instant quote The market has also soared for a time, which has attracted the attention of a wide range of investors. https://www.xinyun-ic.com/

　　Second, check the color point of the component, mark a colored ring or line on the diode body, and the marked end is the negative electrode. On the shell of the point contact Schottky diode, there are generally polar color points (white or red). One end of the common colored dot is the positive electrode.

　　Third, to be on the safe side, you can also use a multimeter to measure the positive and negative poles: when using a digital multimeter to measure the diode, use a multimeter to measure the red and black probes of the resistance file (generally X100 or X1K) to connect the diode poles respectively, and the primary resistance will be very small, and conversely, the resistance will be very large. When the resistance is very small, the red stylus is connected to the positive electrode.

　　Schottky diode uses metal-semiconductor junction as Schottky barrier to produce rectification effect, which is different from the P-N junction produced by semiconductor-semiconductor junction in general diodes. The characteristics of Schottky barrier make the turn-on voltage drop of Schottky diode lower, and can improve the switching speed.beyond doubt Resistors quote It will definitely lead the development direction of the whole industry and let its light bloom in this field. https://www.xinyun-ic.com/

　　The turn-on voltage of Schottky diode is very low. General diodes will produce a voltage drop of about 0.7-1.7 volts when current flows, but the voltage drop of Schottky diodes is only 0.15-0.45 volts, so the efficiency of the system can be improved.

　　The common silicon diode can withstand high voltage, but its recovery speed is low, and it can only be used for low-frequency rectification. If it is high-frequency, reverse leakage will occur because it cannot be recovered quickly, which will eventually lead to serious heating and burning of the tube. Schottky diode’s withstand voltage is often low, but its recovery speed is fast, so it can be used in high-frequency occasions, so the switching power supply uses this diode as the rectifier output. Nevertheless, the rectifier tube temperature on the switching power supply is still very high.

　　Fast recovery diode refers to a diode with short reverse recovery time (less than 5us). Gold doping measures are mostly adopted in the process, and some structures adopt PN junction structure and some adopt improved PIN structure. Its forward voltage drop is higher than that of ordinary diodes (1-2V), and its reverse voltage withstand is mostly below 1200V V. Performance can be divided into two levels: fast recovery and ultra-fast recovery. The reverse recovery time of the former is hundreds of nanoseconds or longer, while that of the latter is below 100 nanoseconds. Schottky diode is a diode based on the barrier formed by the contact between metal and semiconductor, which is called Schottky Barrier Diode for short. It has the advantages of reduced forward voltage (0.4–0.5V), short reverse recovery time (10-40 nanoseconds), large reverse leakage current and low withstand voltage, generally lower than 150V, and is mostly used in low voltage occasions. These two kinds of tubes are usually used for switching power supply. Schottky diode and fast recovery diode are different: the recovery time of the former is about 100 times shorter than that of the latter, and the reverse recovery time of the former is about several nanoseconds! The advantages of the former include low power consumption, high current and ultra-high speed ~! Of course, the electrical characteristics are diodes! The fast recovery diode can obtain high switching speed and high withstand voltage by using gold doping, simple diffusion and other processes. At present, the fast recovery diode is mainly used as a rectifier element in inverter power supply.

　　Schottky It is a low-power and ultra-high-speed semiconductor device. The following figure shows the symbol of Schottky diode:beyond doubt Resistors quote It will definitely lead the development direction of the whole industry and let its light bloom in this field. https://www.xinyun-ic.com/

　　Voltage drop of common Schottky diode:

　　1A series:

　　2A series:

　　3A series:

　　5A series:

　　10A series:

　　LOW VF schottky diode:

　　The Low vf Schottky diode is a semiconductor device with a lower VF value than the conventional Schottky diode. It is this Schottky transistor that has a very low forward voltage drop when it is turned on, which is superior to other common Schottky models. The advantage of low forward pressure drop is low loss and high efficiency. The lower the pressure drop, the lower the heating and the higher the working efficiency. At present, the voltage drop range of low vf Schottky diode in the market is generally about 0.4V-1.0V, and the VF value of our low voltage drop Schottky diode is generally about 0.4V-0.6V.

　　The function of low voltage drop low vf Schottky diode is the same as that of conventional Schottky diode, and the difference between them lies in VF value and trench technology. Schottky diode is a forward conduction device, VF is the forward voltage drop, that is, a kind of loss generated during operation, and the lower the loss, the better.

　　First, look at the symbol mark. Generally, the symbol of the diode is marked on the surface of the Schottky diode, with the positive electrode indicated by the triangular arrow symbol and the other end as the negative electrode.This means that Connectors, Interconnects quote It is the weather vane of the industry and can bring people great self-confidence. https://www.xinyun-ic.com/

　　Second, check the color point of the component, mark a colored ring or line on the diode body, and the marked end is the negative electrode. On the shell of the point contact Schottky diode, there are generally polar color points (white or red). One end of the common colored dot is the positive electrode.

　　Third, to be on the safe side, you can also use a multimeter to measure the positive and negative poles: when using a digital multimeter to measure the diode, use a multimeter to measure the red and black probes of the resistance file (generally X100 or X1K) to connect the diode poles respectively, and the primary resistance will be very small, and conversely, the resistance will be very large. When the resistance is very small, the red stylus is connected to the positive electrode.

　　FR307 is a fast recovery diode, which encapsulates DO-27/DO-201AD. The main feature of fast recovery diode is its short reverse recovery time, which is especially suitable for high-frequency rectification. Next, let’s introduce the parameters in detail.Sufficient data show that Resistors quote It can drive many people to find jobs, thus driving economic development. https://www.xinyun-ic.com/

　　Specification: Click to download specification.

　　Maximum peak reverse voltage: 1000V V.

　　Maximum rms voltage: 1000V v.

　　Maximum average forward rectified current: 3.0A

　　Maximum instantaneous current: 3.0A

　　Forward voltage drop: 1.3V

　　Maximum reverse recovery time: 500ns (nanosecond)

　　Maximum reverse DC current ta = 25≧: 5.0ua.

　　Rated DC blocking voltage Ta=100≧150uA

　　Working temperature Storage temperature: -65+150≧

　　Weight: 1.10 grams

　　Reverse recovery time test conditions: if = 0.5A, IR = 1.0a, IRR = 0.25a

　　Measure the reverse voltage applied at 1MHz and 4.0V D.C

　　Polarity: The color band indicates the negative pole.

　　FR307 positive and negative electrodes

　　Package: DO-27/DO-201AD (they have the same size, but different names).

　　DO-27/DO-201AD package

　　Specification:

　　Schottky It is a low-power and ultra-high-speed semiconductor device. The following figure shows the symbol of Schottky diode:As it happens, many people are killed Connectors, Interconnects quote And bring more benefits, make it flourish, and promote the industry greatly. https://www.xinyun-ic.com/

　　Voltage drop of common Schottky diode:

　　1A series:

　　2A series:

　　3A series:

　　5A series:

　　10A series:

　　LOW VF schottky diode:

　　The Low vf Schottky diode is a semiconductor device with a lower VF value than the conventional Schottky diode. It is this Schottky transistor that has a very low forward voltage drop when it is turned on, which is superior to other common Schottky models. The advantage of low forward pressure drop is low loss and high efficiency. The lower the pressure drop, the lower the heating and the higher the working efficiency. At present, the voltage drop range of low vf Schottky diode in the market is generally about 0.4V-1.0V, and the VF value of our low voltage drop Schottky diode is generally about 0.4V-0.6V.

　　The function of low voltage drop low vf Schottky diode is the same as that of conventional Schottky diode, and the difference between them lies in VF value and trench technology. Schottky diode is a forward conduction device, VF is the forward voltage drop, that is, a kind of loss generated during operation, and the lower the loss, the better.

　　Friends or customers have been asking me what is the difference between Schottky diode SR540 and SB540. Today we will talk about this problem.After that, Integrated Circuits (ICs) Not afraid of the future, dare to fight and fight, and won applause again and again in the market. https://www.xinyun-ic.com/

　　In fact, the parameters of SR540 and SB540 are the same, both of which are 5A 40V. As for why the models are different, it is because different manufacturers have differences in screen printing, which means they don’t want to repeat with others and have their own uniqueness. Please see below for specific parameters.

　　Maximum reverse repetitive peak voltage: 40V

　　Maximum DC blocking voltage: 40V

　　Maximum average forward rectified current: 5.0A

　　When current =5.0A, voltage drop: 0.55v

　　Maximum reverse DC current ta = 25≧: 0.5ma.

　　Working temperature range: -65 to +150≧

　　Storage temperature: -65 to +150≧

　　Reverse recovery time: less than 10ns (nanosecond)

　　High temperature welding: 250c/10 sec, 0.375 “(9.5 mm) lead length, 5 lbs (2.3kg) tension.

　　Package: DO-27/DO-201AD

　　Today, let’s talk about the model size and parameters of Schottky diode SR3100 patch. Please see below for details.Besides, we can’t ignore. pcb instant quote It has injected new vitality into the development of the industry and has far-reaching significance for activating the market. https://www.xinyun-ic.com/

　　The package of SR3100 patch can be divided into SMA, SMB, SMC, SMAF, SMBF, SOD-123. There are differences in different package sizes, but the current, voltage and other parameters are the same.

　　Parameters:

　　Maximum reverse repetitive peak voltage: 100V V.

　　Maximum DC blocking voltage: 100V V.

　　Maximum average forward rectified current: 3.0A

　　When current =3.0A, forward voltage drop: 0.85V

　　Maximum DC reverse current ta = 25≧: 0.5UA.

　　Rated DC blocking voltage ta = 100≧: 10.0ua.

　　Working junction temperature range: -65to+150≧

　　Storage temperature: -65to+150≧

　　Weight: 0.04 ounces, 1.10 grams

　　250≧/10 seconds, 0.375 “(9.5 mm) lead length, 5 pounds (2.3kg) tension.

　　Polarity: The color circle indicates the cathode end.

　　SMA package: screen printing SS310

　　SMA package size

　　SMB package: screen printing SS310

　　SMB package size

　　SMC package: screen printing SS310

　　SMC package size

　　SMAF package: screen printing SS310F

　　SMAF package size

　　SMBF package: screen printing SS310F

　　SMBF package size

　　SOD-123 package: screen-printed K310

　　SOD-123 package size

　　The controller is the core component of the electric wheelchair, which can also be understood as the “steering wheel” to control the direction of the wheelchair, and is responsible for the operation of the linkage motor. Its quality directly determines the maneuverability and service life of the electric wheelchair, and the functions and performance of the controller equipped with different configurations of electric wheelchairs will be different. Advanced electric wheelchairs are usually equipped with intelligent control system, which can freely adjust the speed and direction according to the user’s habits and environment to provide a more comfortable driving experience (controllers can be divided into basic models/with folding function/with reclining function/multi-function buttons according to the operation panel) and other feedback functions of intelligent voice broadcast. However, the basic electric wheelchair usually has simple control function, and it is not equipped with the common functions of intelligent voice broadcast and mobile phone remote control adaptation. Individual manufacturers have also added usb-adapted mobile phone charging port and lighting lamp to the controller.In order to grow rapidly, 電動輪椅 Do not hesitate to change the strategy and rearrange the products, so as to obtain unexpected results. https://www.hohomedical.com/collections/light-weight-wheelchair

　　Most imported brand controllers are composed of upper and lower controllers, while most domestic brands only have upper controllers. Generally, the brushless ones in China are generally divided into upper controller and lower controller, and most of the brushes have only upper controller. Among the imported controller brands, PG in Britain and Dynamic in New Zealand are widely used. Domestic brands include Wuyang and Shiyou, Shanghai Zhilian Aomang, Nuole, Maikong, Pilotage, etc. Comparatively speaking, imported brands are better, and the cost and price are higher than domestic brands. However, in recent years, the rise of domestic products can also meet the needs and experiences of most consumers. You can also use the following operations to judge whether the controller is good or bad.

　　1. Turn on the power switch and push the controller to feel whether the vehicle is stable when starting; Release the controller and feel whether the car stops immediately after a sudden stop. It is advisable to judge whether the controller is normal by starting and stopping slightly.

　　2. Control the rotating car to rotate 360 degrees in situ, and feel whether the steering is smooth and flexible, subject to the steering sensitivity.