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Eagle 30/30 No. 23 – Monostable Multivibrator, 0.0.1

by Carlyn Maw on June 23, 2011, no comments

This is a monostable multivibrator circuit, or “one shot”.  The diference between a monostable and astable multivibrator is that the monostable vibrator has a default or preferred state from which it can be jostled for a only a set period of time. That time frame is determined by C1 & R2, see information about the RC time constant.  In this circuit applying voltage to the trigger T will ground one of the leads of C1, causing it to behave like a short until it can charge again via R2.  Q will read as voltage high during that period. It is normally off.


Again one of the sites from yesterday has a good write up:
but compare it to the circuits on these two pages:
Niether use the extra transistor, but instead apply a switch straight to the base of Q1. The capacitor on the first links page makes it nonretriggerable, I think.