I am playing around with a digital potentiometer (Ti TPL0501) and got it all working as I wish. It is going to replace a regular pot in a control unit in a automotive environment. In the future my idé is to make a product of this maybe.
The digipot is rated for +-5mA on the pot pins and that is OK as the max current is 2.5mA max and 0-5V. I guess (potted PCB) the pot in the control unit is part of a voltage divider. The wiper goes to ground and one side of the pot goes into the control unit.
But how can I protect the digipot pin from over voltage/current?
If lets say the user by accident connects the the digipot output to +12 or similiar?
I cannot use a series resistor to limit current as this would upset the potentiometer resistance?