Quality detection of fast recovery diodes

Fast Recovery Diode (FRD) is a semiconductor diode with good switching characteristics and short reverse recovery time. It is mainly used in electronic circuits such as switching power supplies, PWM pulse width modulators, and frequency converters, as a high-frequency rectifier diode, freewheeling diode, or damping diode. The internal structure of a fast recovery diode is different from that of a regular PN junction diode. It belongs to the PIN junction type diode, which adds a base region I between P-type silicon material and N-type silicon material to form a PIN silicon wafer. Due to the thin base region and small reverse recovery charge, fast recovery diodes have a shorter reverse recovery time, lower forward voltage drop, and higher reverse breakdown voltage (withstand voltage value).

How to judge the quality of fast recovery diodes?

Place the multimeter in the Rx1k range and measure the forward and reverse resistance of the fast recovery diode. The forward resistance is generally a few ohms and the reverse resistance is ∞. If the measured resistance values are ∞ or 0, it indicates that the tested diode is damaged. The detection method for fast recovery diodes is basically the same as the above method, but it is necessary to first determine which pin their common terminal is, and then use the above method to detect each fast recovery diode.