I'm looking for a way to implement reverse polarity protection for a circuit that runs from a CR2032 battery (The operating voltage of the circuit is from 1.8 V to 3.2 V).
I'm considering using the Si4421DY MOSFET as this seems to have low Drain-source on-state resistance. Furthermore, the gate opens at a low voltage of 1.5 V.
However, I'm not able to figure out how much power this circuit consumes when the drain-source is kept open (except for power dissipation caused by the current and the internal resistance? Is there a current going through the gate when voltage is applied to the gate?
Also, do I need to add some kind of ESD protection for the gate pin?