I am trying to build a simple time delay circuit. I have used a 555 monostable configuration for that. schematics is attached.
Now I want that the timer should start when ever i give a trigger input.
now 555 times out irrespective of whether there is an input pulse during the timing cycle.
To give more clarity, the attached schematics is of 555 configuration with time of 10 seconds output pulse.
1. At time T=0 sec I close switch S1 and the pin 3 goes high.
2. At time T=10 sec the pin 3 goes low.
Now even if i close the switch S1 between time T=0 to time T=10, the output at pin 3 will still go low.
What i want is that if i close the switch S1 at time T=5 seconds, the timer should start again and output should remain high till time T=15 seconds.
Basically i want a time delay switch, which should activate immediately, but time out after time "T" which is determined from time of last trigger.
can i use simple RC network connected to a transistor switch where the swith will close immediately on giving the pulse, but will open again after a time delay determined by RC network. and if i give a trigger the circuit again in between the time delay, the time counting should start all over again...
can you please help....
Now I want that the timer should start when ever i give a trigger input.
now 555 times out irrespective of whether there is an input pulse during the timing cycle.
To give more clarity, the attached schematics is of 555 configuration with time of 10 seconds output pulse.
1. At time T=0 sec I close switch S1 and the pin 3 goes high.
2. At time T=10 sec the pin 3 goes low.
Now even if i close the switch S1 between time T=0 to time T=10, the output at pin 3 will still go low.
What i want is that if i close the switch S1 at time T=5 seconds, the timer should start again and output should remain high till time T=15 seconds.
Basically i want a time delay switch, which should activate immediately, but time out after time "T" which is determined from time of last trigger.
can i use simple RC network connected to a transistor switch where the swith will close immediately on giving the pulse, but will open again after a time delay determined by RC network. and if i give a trigger the circuit again in between the time delay, the time counting should start all over again...
can you please help....
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