How to protect pin from high voltage ('disconnect' pin)

[oeliks]

What is the best way to protect pin from external 'high' voltage (10-30-60 or higher V). Is it even possible without external buffer, resistor + clamping ​diodes etc.?

​

Input with high Z, open drain, other methd for "disconnecting" pin will do the job?​

​

I think I cant really phisically disconnect pin in software?

​

​

​I would go with high Z and clamping diode and fuse. But maybe there is better option. I can't add series resistor to reduce power and clamp excess voltage smoothly.

​

Thanks​

[TDK]

You cannot get away from the voltage limits outlined in the data sheet. You cannot disconnect the pin from internal circuitry.

clamping circuit can work, as can inline resistor. You must respect the voltage or injected current limits at all times as given in the data sheet.