In this circuit I am wondering if I really need the n-channel mosfet to control my dual p-channel MOSFET. I think I can drive this straight from the micro. Just want to second opinion before I modify my design.
The CG2_En output can go from 0V to 3.3V. EDIT: The P-Channel MOSFET does not need to switch 20V but it does need to block 20V when it is off. It will only be asked to switch 5V. (Still entertaining answers that require 20V since I have another circuit that will) By default the micro can have its input buffer off presenting somewhat high impedance. Once it wakes it can put out 3.3V. In either state I think the micro would still be subject to a reverse current flow due to the overvoltage. The spec sheet says it can handle an injection current of 1ma (Attiny 1606). @20V with the 47k resistor in place worst case would be (20V-3.3V+0.6V)/47000 = 0.37mA. (I didn't add the 330) Note: This circuit should be initially off. I intend to keep R10 but dump R6 and Q4. Doable?