Why does the Schottky diode heat up badly when it is rectified at high frequency?

The structural principle of Schottky rectifier is very different from that of PN junction rectifier, which is usually called junction rectifier, and metal-semi-conduit rectifier is called Schottky rectifier. With Schottky Schottky, it can only be replaced with Schottky diodes. Schottky diodeSchottky diode, also known as Schottky barrier diode (SBD), is a low-power, ultra-high-speed semiconductor device.

The most notable feature is the extremely short reverse recovery time (which can be as small as a few nanoseconds) and the forward conduction voltage drop of only about 0.4V. It is mostly used as high-frequency, low-voltage, high-current rectifier diode, freewheeling diode, protection diode, and is also used as rectifier diode and small signal detection diode in microwave communication and other circuits. It is more common in communication power supplies, frequency converters, etc.

The main advantages of Schottky rectifier Schottky include two aspects:

1. Since the Schottky barrier height is lower than the PN junction barrier height, its forward conduction threshold voltage and forward voltage drop are lower than those of the PN junction diode (about 0.2V lower).

2. Since SBD is a majority carrier conductive device, there is no minority carrier lifetime and reverse recovery problem. The reverse recovery time of the SBD is only the charging and discharging time of the Schottky barrier capacitor, which is completely different from the reverse recovery time of the PN junction diode. Due to the very low reverse recovery charge of the SBD, the switching speed is very fast and the switching losses are particularly low, making it particularly suitable for high-frequency applications. It has the advantages of high switching frequency and forward voltage drop, but its reverse breakdown voltage is relatively low, most of which are not higher than 60V, and the highest is only about 100V, so that its application range is limited.