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Hello. I have a button connected to 12V and want to fire a solenoid 24V ONCE every push of the button. No matter if the button is pushed 1 sec or one minute. The solenoid should fire more or less 1 sec and then go low EVEN if the button is still pressed. It's like a Trigger on the rising edge only. Is that text clear? I managed to do it with a microncontroller but I want to do it without a microcontroller. The examples using a 555 monostable with one shot didn't work if the button is still pressed (it keeps the solenoid ON until button is relased and I don't that that like that). Can you help with a solution with real values that I can simulate in Proteus? PS: I know it is a little off topics of this site. Thank you

You may take a look at

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It may not work if the frequency is too fast.

As shown, the switch is "ON". The simulation kicks the votlage (from the source) at 5 seconds. You may note that, with the simulation, the voltage at the load is there for a little bit more than one second. The exact timing depends on the temperature, the PMOS, the capacitor C1 and the resistor C1 (with their tolerances).

I would personally use a Tiny-Arduino for more versatility and precision, even if this circuit is relatively simple, thanks to the DSDP switch.

I suggest you put a flywheel diode around the solenoid. Otherwise, in real life you may find you get hard to diagnose component failures.