avalanche transistors

[zener57]

i'm looking for help in finding transistors that will avalanche to produce a 1ns pulse with around 80V input - any ideas?

thanks

 

[footprint]

avalanche transistor

you can try 2n2369

Added after 2 minutes:

or you can try SRD

 

[aProgrammer]

2n2369 avalanche

I suggest you to see this (great) book :

Analog Circuit Cookbook


there are a section titled
"Working with avalanche transistors"

 

[zener57]

2n2369 rise time

i've tried the 2n2369's out (and others with 2n prefix) however i seem to only be getting around 5ns output pulse. the 2n2369's did appear to work at 80V but many of the other transistors require higher voltage, i.e. >120V to avalanche.

i'll also check out the book

thanks

 

[footprint]

Pulse width prodeced by avalanche transistors sometimes depend on the output capacitor!
you can reduce the output capacitor for 1ns width

 

[zener57]

i'm going into 200pF, is this small enough?

 

[footprint]

too large ,you can try 10p

 

[zener57]

10pF did not seem to reduce the output pulse width. does the trigger rise time effect the actual pulse rise time?