🚀 go-pugleaf

Re: using a 555 timer as a  one shot timing device:


One thing to consider when using 555's : some varieties,
in some "one shot" configurations,
when triggered, will turn the output on for a time as defined by
the RC  combo regardless of the duty cycle of the trigger
(ie: the output of the 555 will go high for the prescribed time);

others will ADD the on time of the trigger to the time of the
RC (ie: the output of the 555 will go high when activated and the RC
timing will not go into effect until the trigger signal goes off).

This extra time can be significant when connecting to mechanical switchs.