Re: another fast one-shot

On Wed, 12 Jun 2024 11:11:28 -0700, john larkin wrote:

On Wed, 12 Jun 2024 17:22:49 -0000 (UTC), Cursitor Doom
<cd999666@notformail.com> wrote:
 

On Wed, 12 Jun 2024 09:33:17 -0700, john larkin wrote:
>

Here's another idea for a fast one-shot. This is the just-apply-money
version and should get close to 1 ns pulse width and should easily
trigger at 150 MHz.
 
https://www.dropbox.com/scl/fi/1okfo8964bw5m53mjmxs6/

Pecl_One_Shot_1.jpg?rlkey=dwus6qjyqsynl2rv6uje2xxtj&raw=1

 
I can use the other half of the dual comparator elsewhere. This one
has programmable hysteresis too.

>
Exposing my contemptworthy ignorance here no doubt, but what exactly is
it that is fast about this design, John? And what would its application
be?

 
It would have a leading-edge prop delay of 350 ps, a minimum pulse width
just over 1 ns, and would easily trigger at 150 MHz. Integrated
one-shots, xxx123 types, are always terrible, even the obsolete ECL
ones.
 
It would be a programmable delay in a number of possible products,
including some optical modulators. Just playing right now.
 
More dollars could certainly do something faster, but as long as
customers connect boxes with cables, faster isn't worth a lot. Light
just moves too slow.
 
Any suggestions for a faster one-shot?

Not from me! I couldn't even design a PID controlled PLL without recourse
to the 'net.