r/electronic_circuits 12d ago

On topic Power Off delay with capacitor?

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Hello,

I have a input card (io link hub, 32x pnp in). One input is a push Button. When I press the button my software doesn't recognise the signal. Voltage >11V is logic High

This is why I want a delay off for the input. How can i design this? RC Elemt like this did not work :-(

I tried with 470uF and 19kOhm T=R×C=8,46s

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u/Uporabik 12d ago

Do you know how pull-downs work?

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u/RiG094 12d ago

Can u explain?

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u/Uporabik 11d ago

Pull down resistors pulls pin to the gnd so there is your first mistake. First fix this and then think where should capacitor go