NE555 Basic Monostable

Circuit : Andy Collinson
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Use of the ubiquitous 555 timer in monostable mode.

555 monostable circuit diagram Circuit Notes:
Here the popular 555 timing IC, is wired as a monostable. The timing period is precise and equivalent to:-

1.1 x R1 x C1

With component values shown this works out at approximately 1.1msec.The output duration is independent of the input trigger pulse, and the output from the 555 is buffered and can directly interface to CMOS or TTL IC's, providing that the supply voltages match that of the logic family.

555 monostable timing diagram

The timing diagram above shows the output pulse duration, the trigger input and the output at the discharge terminal of the IC.

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