Views: 0 Author: Site Editor Publish Time: 2023-08-01 Origin: Site
A rectifier diode is a semiconductor device that converts alternating current to direct current. Usually it consists of a PN junction with two terminals, positive and negative. The most important characteristic of a diode is unidirectional conductivity. In the circuit, current can only flow in from the positive terminal of the diode and flow out from the negative terminal.
The working principle of the rectifier diode is as follows: under the forward voltage, due to the high forward doping concentration, the electrons move to the P region, and the holes move to the N region. When the two meet at the PN junction, these electrons are captured by the holes, a small amount of heat is generated, which narrows the charge region in the PN junction region, allowing current to pass. Under the reverse voltage, electrons and holes will not meet at the PN junction, so the reverse current of the rectifier diode is very small.
According to the type of material and process, it can be divided into ordinary rectifier diodes, fast recovery rectifier diodes, ultra-fast recovery rectifier diodes, Schottky diodes and power diodes.Rectifier diodes are generally planar silicon diodes, which are used in various power rectification circuits. When selecting a rectifier diode, parameters such as its maximum rectification current, maximum reverse operating current, cut-off frequency, and reverse recovery time should be considered. The rectifier diodes used in ordinary series regulated power supply circuits do not have high requirements for the reverse recovery time of the cut-off frequency, as long as the rectifier diodes with the maximum rectification current and maximum reverse operating current meet the requirements are selected according to the requirements of the circuit. For example, 1N series, 2CZ series, RLR series, etc.
Ordinary rectifier diodes have the advantage of strong reverse withstand voltage capability, but the switching speed is slow; fast recovery rectifier diodes have faster switching speed and higher reverse withstand voltage capability;
Compared with fast recovery rectifier diodes, ultra-fast recovery rectifier diodes have shorter recovery time and better high-frequency characteristics. Schottky diodes have lower forward voltage drop and faster switching speed, and power diodes are suitable for high voltage and high current applications.
When selecting a rectifier diode, parameters such as its maximum rectification current, maximum reverse operating current, cut-off frequency, and reverse recovery time should be considered.
To sum up, different rectifier diodes are used in different occasions, and a suitable rectifier diode should be selected according to the needs to ensure the stability and reliability of the circuit.
