Understand the characteristics of several common chip diodes

1. Zener diode is a device made of the voltage stabilizing performance shown by the reverse breakdown characteristics of the pn junction, also known as zener diode or reverse breakdown diode, which plays a role in stabilizing the voltage in the circuit. It uses the characteristic that the reverse voltage does not change with the reverse current within a certain reverse current range after the diode is reverse breakdown. It is usually made of silicon semiconductor materials by alloy method or diffusion method. It not only has the unidirectional conductive characteristics of ordinary diodes, but also can work in the reverse breakdown state. At present, the voltage stabilizing tube with low temperature coefficient is composed of two voltage stabilizing tubes in reverse series connection. When the two voltage stabilizing tubes are in positive and negative working conditions, they have positive and negative temperature coefficients, which can obtain good temperature compensation.

2. Fast diode includes fast recovery diode and schottky diode, which are mainly used in high-frequency rectifier circuit, high-frequency switching power supply, high-frequency resistance capacitance absorption circuit, inverter circuit, etc

The reverse recovery time of fast diode can reach 10ns. It is a semiconductor diode with good switching characteristics and short reverse recovery time. It is mainly used in switching power supply, pwm pulse width modulator, frequency converter and other electronic circuits as high-frequency rectifier diode, continuous current diode or damping diode.

Schottky diode is made of potential barrier layer formed by contact between metal and semiconductor. Its main characteristics are low forward conduction voltage drop (about 0.45v), short reverse recovery time and low switching loss. It is a low power consumption, ultra-high speed semiconductor device, widely used in switching power supply, frequency converter, driver and other circuits, and used as high-frequency, low-voltage, high current rectifier diode, freewheeling diode and protection diode, Or it can be used as rectifier diode and small signal detector diode in microwave communication circuits.

3. The structure of rectifier diode is mainly plane contact type, which is characterized by large allowable current and high reverse breakdown voltage. It is widely used in circuits with low processing frequency. The main consideration of rectifier diode in use is that the maximum rectifier current and maximum reverse working voltage should be greater than the value in actual work.