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Delaying a monostable timer.

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Bammurdo

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Hello Electro Tech members...
I need some help.

Basically, I'm trying to build a circuit that has a switch (Push-To-Make) That, when pressed, will use an RC network to count to 5seconds. Once that time has passed, it will pass onto a 555 timer that will turn on a LED (for example) for about 10 seconds.

I'm not entirely sure on how to go about this... I've played around with the RC network, but I just don't know how to connect both the timer & the RC network so that one delays the other.

Any help is greatly appreciated

Thanks
Bam

Edit: Here's an animation to show my problem
**broken link removed**
 
Last edited:
you can use two 555 timers, first one working as 5 sec monostable and the second driven by the first timer output and stay ON for 10sec and switches off.may be you have to invert the output of 1st time by using a common collector amplifier( or inverting buffer gate, like a NAND with both inputs looped.)
you see the datasheet of 555 for monostable timer
application.
 
Last edited:
You can use a 556 which is a dual 555.
 
@mvs sarma:

This is exactly what I tired first - but what happens is:
[ Input ( Pull Down - clicking the switch gives you a pulse of 0V) ] -> [First Timer] -> [Looped NAND gate (working as a NOT)] -> [Second timer]

When you click the input button, you get a pulse of 0V going into timer one
The timer's output goes high, and it counts to 1.1RC (5 seconds)
This high voltage goes into the NAND gate - giving you a pulse of 0V lasting 5 seconds.
This pulse will trigger the second timer, which will then count to 10 seconds.

But, That means the two timers will run in sync.
I need it to be like:
Pulse of 0V into first timer -> Timer counts to 5 & goes low again -> Second timer triggered -> Light on for 10 seconds -> turns off until next pulse.

Any ideas :/?

@crutschow:
Thanks, I'll bare that in mind
 
Last edited:
try this element
the switch should be momentary action push to ON.
 

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