Does Monostable pulse stay HIGH whilst input pulse is HIGH?

Status
Not open for further replies.

cupoftea

Advanced Member level 5
Joined
Jun 13, 2021
Messages
2,617
Helped
54
Reputation
108
Reaction score
115
Trophy points
63
Activity points
13,729
Hi,
Please can you confirm that with CD74HC123 Monostable IC….

If R = 180R, C=2n2
And
If !(1A) is LOW and !(1R) is HIGH..

..Then, if 1B is taken high for 1000ns, then Q will go HIGH for 396ns (R x C), then go LOW

That is, Q will not be kept HIGH by the 1B pulse being high for 1us?

CD74HC123 Monostable IC datasheet:-

Also, if one of the monostables on a chip isnt used, would you agree, the CX and CXRX pins need grounding?
--- Updated ---

Sorry, here is the correct datasheet
CD74HC123
 
Last edited:

A "retriggerable" monostable will stay high (triggered)
as long as the input is high. Whether, if that exceeds
timeout, the timeout then happens or was "buried",
you'd have to squint real close at the DS.

non-retriggerable ones work off the leading edge
and need the trigger to go low, to get another LH
trigger event.
 
Status
Not open for further replies.
Cookies are required to use this site. You must accept them to continue using the site. Learn more…