EEVblog Electronics Community Forum
Electronics => Beginners => Topic started by: Spemo on April 14, 2021, 07:36:41 pm
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Hello everyone,
I'm trying to find a solid state solution for a small problem.
The situation is as follows:
A Timing circuit with a CD4060BE and a 4027BE, the output is a 1Hz signal with a 50% Duty cycle.
This 1Hz 50% signal goes into a "signal shortener" which is made up out of two DPDT relays, a transistor, capacitor and resistor, to shorten the signal to a short pulse, my guess is around 15% on, 85% off.
Now, I have two problems with this: first, relays. It works, but the noise it creates is not wanted. Second, there is reliability to think about.
I'm looking for a really simple solution that changes the duty cycle of the given signal from 50% to let's say 15%, or adjustable at best.
I've tried googling and the forum search, but I couldn't find the answer I was looking for.
Maybe there is an obvious solution for this... If you happen to know one, please share it with me, it would be apreciated a lot!
Thank you for your time,
Daniel
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If you AND the last two bits of the counter you will get a 25% duty cycle.
If you AND the last three bits of the counter you will get a 12.5% duty cycle.
etc...
Or you can NOR them.
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.... and if for any reason you cant tap into the counter, so have to work with the 1Hz 50% signal, you could use a monostable.
Are there any other constraints on the required output signal?
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Hi!
The monostable, that's the solution I'm looking for!
Silly me, since it's already in a different part of the complete circuit, with a 555... Thanks a lot!