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From: john larkin <jlarkin_highland_tech>
Newsgroups: sci.electronics.design
Subject: Re: The emitter-coupled monostable as slow differential amplifer
Date: Sat, 20 Jul 2024 14:04:10 -0700
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On Sat, 20 Jul 2024 15:29:58 +1000, Bill Sloman <bill.sloman@ieee.org>
wrote:

>About a month ago John Larkin dismissed the emitter coupled monostable 
>with "It's really a slow diffamp, not a one-shot."
>
>If you feed a really slow pulse into it, it can look that way.
>The 3.3pf capacitor at C1 doesn't feed through much current if you drive 
>the input with a slow edge
>
>The simulation below demonstrates it working exactly that way.
>
>No sensible circuit designer would deliberately drive it with a very 
>slowly rising and falling pulse  - if you want it to work as a 
>monostable pulse stretcher, you have to drive it with a pulse that is 
>narrower than the one you want to get out.
>
>Integrated circuit monostables don't have that limitation, but they are 
>more complicated, and slower. There was an ECL monostable that went down 
>to 10nsec, but the emitter-coupled monostable lets you get down to 
>1nsec, if you use it right.
>

That wasn't my point. My comment wasn't about the trigger risetime but
that if you put in a long trigger, you get a long output. It's hardly
a one-shot.  The input and output levels are weird too.

If course a proper one-shot should fire cleanly on a fast or slow
rising edge.

https://www.dropbox.com/scl/fi/idliehdrx7dr5fnffr4f9/28S505A.pdf?rlkey=gkmhx0r2fe4clu4qf98qoig03&dl=0