Fastest Switching diode

[emranshd]

Hi, can anyone tell me what type of diode is the fastest switching diode? i want to find a diode to clip the negative peak of a nano-second pulse. what is the most suitable diode for sub-nano second switching? Thanks

Imran

 

[crutschow]

What is the pulse voltage?

How sub-nanosecond?

 

[emranshd]

dear crutschow
Minimum Pulse width is 1ns and maximum voltage level is 20V.

 

[crutschow]

For that a small-signal Schottky diode should work.

 

[indulis]

When the term "fast switching diode" is used, it refers to it's reverse recovery time and not it's turn-on time. Finding turn-on time specs for diodes isn't exactly easy.

 

[crutschow]

When the term "fast switching diode" is used, it refers to it's reverse recovery time and not it's turn-on time. Finding turn-on time specs for diodes isn't exactly easy.

That is true. But the turn-on time for most signal diodes is quite fast and does not vary much with the fabrication process. That's why it is not generally specified.

 

[indulis]

But the turn-on time for most signal diodes is quite fast...

"Quite fast" is still a relative term... how fast is "quite fast"? I've looked for spec's in the past but was unable to find any.

 

[crutschow]

"Quite fast" is still a relative term... how fast is "quite fast"? I've looked for spec's in the past but was unable to find any.

Yes, it's seldom mentioned. Here is an article on some forward turn-on time tests of several diodes.

 

[emranshd]

I have tried 1N5819 and 1N6263 schottky diodes but none of these is working. what can be the alternative choice?

 

[crutschow]

I have tried 1N5819 and 1N6263 schottky diodes but none of these is working. what can be the alternative choice?

You likely need a Schottky diode rated for RF.

Show a diagram of the circuit that the diode connects to. What is the impedance of the signal source to the diode? It's hard to make a recommendation without knowing those things.