1. Voltage regulator diode

Voltage regulator diode, sometimes called Zener diode. The principle is to use the pn junction reverse breakdown state, the current changes in a wide range but the voltage is basically unchanged. Zener diodes are graded according to breakdown voltage. If you want to get a higher voltage, you can use them in series, so you can get a higher output constant voltage. Such as 1N4620 voltage regulator 3.3V, 1N4625 voltage regulator 5.1V and so on. Power ranges from 200mW to 100W.

2. Light-emitting diodes

It is made of gallium (ga), arsenic (As), phosphorus (p) and other compounds. Gallium arsenide diode emits red light, silicon carbide diode emits yellow light, etc. This diode forward drive, low operating current, small current, especially suitable for long service life, color variety of patch lights, widely used in billboards, digital screen displays and other need to light the occasion.

3. Rectifier diode It can be imagined that the rectifier diode is used for rectification. It uses unidirectional conduction to rectify alternating current into DC output. The requirement of reverse recovery time of rectifier diode cutoff frequency is not very strict for normal regulated power supply. Generally, it can meet the largest rectification current and the largest reverse operating voltage. The rectifier diodes include 1NXX series and 2CZ series. For high-frequency switching power supplies, rectifier diodes with high operating frequency and short reverse recovery time should be used, such as RU series, V series, 1SR series, etc. Higher voltages can be rectified by Schottky diodes.

4. Detection diode

Detection is the removal of the modulated signal from the input signal, with the magnitude of the rectification current, usually 100mA, as the cut-off point. Usually the output current is less than 100mA called detection. Detector diodes are commonly used in small signal circuits, such as transistor radios and television sets.