Re: fast discrete PHEMT one-shot

"John Larkin" <jjSNIPlarkin@highNONOlandtechnology.com> wrote in message
news:9qdc4jdovsm0rousj88ngtn2bj6env9l48@4ax.com...

On Fri, 17 May 2024 00:40:32 +1000, Bill Sloman <bill.sloman@ieee.org>
wrote:
>

On 16/05/2024 11:15 am, John Larkin wrote:

On Wed, 15 May 2024 22:46:27 -0000 (UTC), piglet
<erichpwagner@hotmail.com> wrote:
>

John Larkin <jjSNIPlarkin@highNONOlandtechnology.com> wrote:

>
https://www.dropbox.com/scl/fi/agatzclr8pvr5470g6mc4/Phemt_One_Shot_1.jpg?rlkey=cwnx0qd7ajgnh8otf627x5lku&raw=1
>
Regular monostables are terribly slow. This one has low prop delay and
high rep-rate, if the sim is to be believed.
>
SAV541 is mostly specified as an RF part, but it's a dynamite switch.
>
I can post a link to the files if anybody wants to play with this. All
my values are first guesses, no math involved, and it works!
>
My SAV541 Spice model is a revision of Phil Hobbs' original.
Mini-Circuits is adamant that they will never provide Spice models, a
typical RF-bigot attitude.
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>

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Yay! Eccles-Jordan ride again.

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1918!
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I think that was a bistable. I don't know when the monostable was >
invented.

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https://en.wikipedia.org/wiki/Multivibrator
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has a two quotes from 1942 one from 1943 and two from 1949 which make it
clear that monostable had been invented by then. It sees it as a cut
down bistable, so Eccles-Jordan is probably a good name.
>
Since the first multivibrator circuit, the astable multivibrator
oscillator, was invented by Henri Abraham and Eugene Bloch during World
War I, it probably isn't the right name.
>
https://apps.dtic.mil/sti/tr/pdf/AD0410225.pdf
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is a 1963 Ph.D. on the bistable circuit.
>

People tend to roll eyes when I use one-shots in logic designs. I
can't see why.

>
You can't trigger a one-shot immediately after it has been triggered,
and the pulse width you get can be reduced if you re-trigger it too soon
after it has generated it's pulse, when it hasn't entirely recovered.

>
The SN74123 retriggerable one-shot, and a Fairchild equivalent, are
over 50 years old.
>
And "it's" is not the possessive form. It's means "it is."

But it can also mean "it has" and who cares anyway.
I often find, when typing fast, that I used the wrong form when I re read my
sentence.
I even typed dentence then and had to change the d.

One-shots were frequently used in logic designs when gates were four per
package because designers still knew what they were doing with components
such as resistors, capacitors, inductors etc.
I'm sure some still do but not many.
50 years from now it will likely all be done by AD. (Artificial Designer).