I am using the following 555 monostable circuit for a 1 second pulse. The pulse drives an A.C. Universal motor for 1 second.
Now i am faced with a problem where the circuit could be falsely triggered. I dont want the monostable to be re-triggered once its triggered for a selected time say 0.5 seconds. To be more specific...
At time T=0, I give trigger pulse by opeaning the NC switch.
I get out put pulse from 555 pin 3 for a duration of 1 second.
At time T=1 sec the output pulse goes low.
(i am ignoring the internal rise and fall time delays )
Now i dont want to trigger 555, till time T=1.5 seconds even if i open the switch by mistake.
This means that even after the output pulse of 555 is low at time T=1, the circuit shoud prevent the triggering till another 0.5 seconds.
i.e. at time T=1.3 seconds if i again try to trigger the 555 timer by opeaning the NC switch, it should not be triggered.
I should be able to re-trigger the 555 timer only after time T=1.5 seconds.
How do i build this logic in this circuit?
Can you please help?
Thanks
Now i am faced with a problem where the circuit could be falsely triggered. I dont want the monostable to be re-triggered once its triggered for a selected time say 0.5 seconds. To be more specific...
At time T=0, I give trigger pulse by opeaning the NC switch.
I get out put pulse from 555 pin 3 for a duration of 1 second.
At time T=1 sec the output pulse goes low.
(i am ignoring the internal rise and fall time delays )
Now i dont want to trigger 555, till time T=1.5 seconds even if i open the switch by mistake.
This means that even after the output pulse of 555 is low at time T=1, the circuit shoud prevent the triggering till another 0.5 seconds.
i.e. at time T=1.3 seconds if i again try to trigger the 555 timer by opeaning the NC switch, it should not be triggered.
I should be able to re-trigger the 555 timer only after time T=1.5 seconds.
How do i build this logic in this circuit?
Can you please help?
Thanks
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