Is this ok to control the power to an IC(from a uC)? (zener probably end up as an led for visual)
The idea is simple. The zener biases the gate of Q2 when Q1 is on. R1 is the "load".
I'd like to do this with as few parts as necessary but this seems to be an ok method? (the values are arbitrary in the schematic)
If +V is known, you don't even need the zener.
What peak current, dV/dt, etc. is needed? If it's good, then sure it's okay.
I saw a similar turn-on circuit from an LCD TV that was shown with a
100k series gate resistor, presumably because there was an awful lot of bypass capacitance after the PMOS. Evidently, they got away with that. (At least for a while. Maybe they ultimately picked a little too small a transistor, since the reason I saw this circuit is because someone was troubleshooting the circuit and had drawn the schematic and posted it. His PMOS had vaporized...)Tim
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