1. Power adapter fuse: It is mainly used for overload protection. If the fuse is properly placed in the circuit, the fuse will cut off the current when the current abnormally rises to a certain height and heat, thus protecting the safe operation of the circuit.

2. Inductance coil (also known as choke coil): blocking effect and tuning, frequency selection effect.

3. Rectifier bridge: Convert alternating current to direct current.

4. Varistor: It is mainly used for voltage clamping when the circuit is subjected to overvoltage, absorbing excess current to protect sensitive devices

5. PWMIC (integrated circuit): Using a certain process, the transistors, resistors, capacitors, inductors and other components and wiring required in a circuit are interconnected, and made on a small or several small semiconductor wafers or dielectric substrates , and then encapsulated in a tube case to become a miniature structure with the required circuit functions; in which all components have been structurally formed as a whole, making electronic components move towards miniaturization, low power consumption, intelligence and high reliability. a big step.

6. Switching transformer: The DC input voltage is regarded as a series of DC pulse voltage, that is, unipolar pulse voltage, through the function of controlling the switch on and off, which directly supplies power to the switching transformer.

7. Electrolytic capacitors: Electrolytic capacitors are named because they use electrolytes as electrodes (negative electrodes). One end of the electrolytic capacitor is positive and the other end is negative, which cannot be reversed. The positive terminal is connected to the positive terminal of the rectifier output circuit, and the negative terminal is connected to the negative terminal of the circuit. In all circuits that need to convert alternating current into direct current, setting the filter capacitor will make the working performance of the electronic circuit more stable, and also reduce the interference of the alternating ripple on the electronic circuit.

8. Power adapter high-power switch tube: It is one of the core components in the switching power supply. The switching power supply can work "one on and one off", and the switch tube is indispensable.