Monostable multivibrator

KeithWalker

Joined Jul 10, 2017
1,147
D3 is in the circuit to bias the emitters of Q1 and Q2 to about +0.7 volts. That ensures the when one of the transistors is conducting, the other one is turned hard off.
Regards,
Keith
 

schmitt trigger

Joined Jul 12, 2010
312
Where did you find the circuit?

This circuit appears to have come from one of the several John Markus books.
Many of those books collected thousands of circuit snippets, each with a very brief description.

With emphasis on "very brief."
 

KeithWalker

Joined Jul 10, 2017
1,147
From my understanding, only when Vi goes negative (about -1.2V) does the output go high

But see.. (Made output pulse longer than input) but think output should not be on after it had gone down
Q2 will stay off until the 750pf capacitor charges up through the 10K resistor.
Keith
 
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