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Circuit Fault Tracker
When repairing the amplifier circuit of radio, tape recorder, power amplifier, combination speaker, etc., the fault finder can be used to determine the fault location quickly and accurately. It has the characteristics of compact, light and easy to carry, and can be used as a regular tool for elec...Read more -
Infrared radiation alarm circuit
This circuit is mainly composed of power supply circuit, infrared transmitting circuit, infrared receiving circuit, logic processing circuit and alarm circuit. The circuit principle diagram of this infrared anti-theft alarm experimental model is shown in the following figure. VT7, VT8 and relate...Read more -
Sunday reminder device
The circuit shown in the picture is one that works on a seven-day weekly cycle. You can switch S1 on the diagram within seven days. Select a day as a reminder day. In order to remember a particular job, event or other important thing that should be done that day, the circuit’s reminder mod...Read more -
Energy saving LED flashlight circuit
The flashlight battery is not durable, not too long to replace the battery, which will bring a lot of trouble. Recently, an energy-saving LED flashlight was modified with a small flashlight to solve this problem. Due to the use of a dedicated LED driver integrated circuit, the original small flas...Read more -
Simple and practical LED light driver circuit
LED lighting set low power consumption, long life and other advantages, is becoming increasingly popular. With the continuous decline in prices, LED has begun to be applied in home lighting. Recently contacted several commercially available 36-head, 60-head LED lights, power consumption is only a...Read more -
Switching transformer: ② Pulse sequence magnetization of transformer core
Pulse sequence magnetization of single-excitation switching power supply transformer core part 2 The magnetic field strength H drops to zero, but the magnetic flux density in the transformer core can not follow the magnetic field strength to zero, but can only drop to a residual value of magnetic...Read more -
Switching transformer: ① Pulse sequence magnetization of transformer core
Magnetization of the core of a single-excitation switching power supply transformer by pulse train part1 For simplicity, we equivalent the single-excited transformer switching power supply to the circuit shown in Figure 2-1, where we regard the DC input voltage through the control of the switch o...Read more -
Switching Power Supply Vs Transformer
A transformer is a device that transforms voltage, current and impedance based on the principle of electromagnetic induction. The primary application of transformers is in AC circuits. Switching power supply is the use of modern power electronics technology, control switching transistor on and o...Read more -
Detection method of inter-turn short circuit in switching power supply transformer
Judgment of short circuit between turns of switching power transformer: 1. Weld two leads on the high-frequency low-voltage output side of the switching power transformer with a 12-volt switching power supply (that is, before entering the rectification filter), and then string a 12V2W small bulb ...Read more -
The working process of flyback isolated switching power supply
Flyback isolated transformer switching power supply, first of all, it is flyback, in line with the definition of “flyback”, that is, flyback is the switch tube cut-off, the transmission of energy; Secondly, it has an isolated transformer, this transformer plays an isolation role, and ...Read more -
Why is the switching power supply using a high-frequency transformer small in size?
The reasons for the small volume of switching power supplies using high-frequency transformers mainly include the following aspects: 1. The high-frequency transformer in the switching power supply works at a frequency much higher than the power frequency (such as 50/60Hz), usually at a few kHz to...Read more -
What if MOS is overcharged when switching power supply cuts load? Try this method!
The prototype main control IC for this debugging is a CR6842S, which is a highly integrated current control PWM controller, which can be used for medium to large off-line power converter. The main features are: low starting current, built-in soft start, green mode unique frequency conversion and ...Read more