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One shot is a monostable multivibrator, it is normally in a stable state but once triggered it changes to an unstable state.

But I can't understand the difference between a nonretriggerable and a retriggerable One shot.

Can somebody please help me understand it ?

Binarylife
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2 Answers2

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In a retriggerable MMV a new trigger during a pulse will restart the pulse time, and thus extend the current pulse.
If the pulse time is 10 s and you would retrigger 6 s after the first trigger you would get a 16 s pulse.

enter image description here

In a non-retriggerable MMV the second trigger will be ignored and you'll get a 10 s pulse:

enter image description here

stevenvh
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    It's worth noting that in a retriggerable device, there is a time relative to the falling edge of Q (could be before or after) before which a retrigger event is guaranteed to be ignored, and a later time (could still be before the falling edge of Q) after which a retrigger event is guaranteed to be effective. Trigger events occurring between those times may be ignored, may start a normal interval, or may start a "runt" interval, or may behave oddly (possibly causing an interval which starts or ends later than expected). – supercat May 07 '12 at 16:51
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This concerns the circuit's response to additional trigger pulses while it's in a triggered state (is outputting a pulse). In a retriggerable monostable, additional input pulses will extend the output pulse by keeping the circuit in the unstable state, while in a non-retriggerable one they will have no effect. See wikipedia.

Thorn
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