what is fas switching diode

[andro]

what is meant by fast switching diode and what is the use?
what is the different between it and ordinery pn junction?
and when should i use it?
i know for most of you this is a simple question but i am a little confused

thanks

 

[FvM]

A "fast switching diode" is an ordinary pn junction diode with certain parameters, particularly reduced reverse recovery time. You can refer to manufacturer datasheets and general literature to learn about quantitative values, or a semiconductor text book how it's achieved in diode design.

 

[Tahmid]

Hi andro,
The main characteristic of a fast switching diode is the reduced reverse recovery time. eg. A UF4007 has a reverse recovery time of about 75ns, compared to about 1us of 1N4007. In high frequency circuits, if the diode does not turn off quickly before again it turns on, it may get damaged. eg, in SMPS circuits fast switching diodes are widely used.
Hope this helps.
Tahmid.

 

[KJ6EAD]

When we first learn about diodes, we're just taught that it allows current to flow in one direction only, and everything occurs instantaneously. That's a so-called "ideal" diode. Here's a more detailed explanation of what really happens: **broken link removed**.