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I need a universal input for MCU (STM32) for connecting external mechanical and magnetic sensors (HAL with open collector), and a universal output 0/5V (0/3.3V), all of which is resistant to connection of at least 24V and resistant to ESD in an industrial environment. With HW debouced mechanical switch , but with a short reaction time.

I came from the classics, everything important is in the picture

V+ for R1 and  IC1 is derived from +V over isolation diode

supplemented with a capacitor and a 5V6 zener diode.

However, I'm not sure if 100uA is not enough for a mechanical button?

R1,C1 at least doubles the ESD protection of the 74HC to the input diodes

What do you think about that?

Isn't 100uA a little low for a mechanical switch?

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