I'm designing a timer circuit and the 555 IC has an unacceptable flaw. In monostable, if the trigger is held longer than the set time, the output will remain high until the trigger is released with no delay. This thread, https://forum.allaboutcircuits.com/threads/monostable-555-trigger-release-issues.113131/, has a solution that will cause the output go low after the set time, but my needs are different. I want a circuit that will output high while the input is high AND a set time after input goes low.
Truth table:
As I wrote this, I though of a solution; use the solution from the aforementioned thread with an OR gate from the 555 output and initial input.
If anyone has a better solution, I'd be happy to read it.
Truth table:
Input | Output |
1 | 1 |
Falling edge | 1 until timer ends |
0 (after timer ends) | 0 |
As I wrote this, I though of a solution; use the solution from the aforementioned thread with an OR gate from the 555 output and initial input.
If anyone has a better solution, I'd be happy to read it.
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