Which recovery time is shorter, Schottky or fast recovery diode? — SUNMATE
Which recovery time is shorter, Schottky or fast recovery diode?
Schottky is a barrier diode formed at the end of metal and semiconductor. It is conductive with most carriers. Its reverse saturation current is much larger than the PN junction of fast recovery diode conductive with a few carriers. Moreover, the storage effect of a few carriers is very small, and the reverse recovery time is certainly much smaller than fast recovery diode.
The size, process and withstand voltage level of the diode will affect the conduction voltage drop and reverse recovery time. Large size diodes usually have high VF and tRR, which will cause large losses. Switching diodes are generally divided into "high speed", "very high speed" and "ultra high speed" diodes by speed. The reverse recovery time decreases with the increase of speed. The tRR of the fast recovery diode is hundreds of nanoseconds, while the tRR of the ultrahigh speed fast recovery diode is tens of nanoseconds.
In low power consumption applications, one alternative to fast recovery diodes is Schottky diodes. The recovery time of such diodes is almost negligible, and the reverse recovery voltage VF is only half of that of fast recovery diodes (0.4V to 1V). However, the rated voltage and current of Schottky diodes are far lower than those of fast recovery diodes, and cannot be used in high-voltage or high-power applications. In addition, Schottky diode has higher reverse leakage current than silicon diode, but these factors do not limit its application in many power supplies.
The recovery time of fast recovery diode is 250-500ns
The recovery time of ultra fast recovery diode is 75-250ns
The recovery time of Schottky diode is about 10ns
And their forward conduction voltage also varies.
Schottky diode is a Schottky barrier diode based on the potential barrier formed by the contact between metal and semiconductor, which is called Schottky diode for short. Schottky diode is a low-power, ultra high-speed semiconductor device. Its reverse recovery time can be as short as several nanoseconds (2-10ns nanoseconds), the forward voltage drop is only about 0.4v (0.4-1.0V), and the rectifier current can reach thousands of amperes. Moreover, the reverse leakage current is large, and the withstand voltage is low, generally lower than 150V, which is mostly used in low voltage situations.