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I want to use a p-channel MOSFET to turn off and on the power to a 6 V l7806 voltage regulator that powers a 6 V servo. The reason is to save battery power.

The controller is a 5 V Arduino. It is my understanding that I cannot directly drive the MOSFET because it needs to be driven to the 6 V to shut off the p-channel MOSFET.

Can an n-channel MOSFET be used as the driver? If so, what would the circuit look like?

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I searched for examples before I posted this. Then directly on this site I asked the question differently and found my answer.

p-channel MOSFET switch

Was exactly what had searched for before and now found.

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    \$\begingroup\$ Yes, if you need a high-side switch where V+ is higher than your logic level, use an N-channel MOSFET to drive the gate of the P-channel MOSFET. You can also use an NPN transistor to drive the P-channel MOSFET. Low-current NPNs are really cheap, but you will potentially waste more power. This is what I do for a pulsed application. \$\endgroup\$
    – Mattman944
    Commented Jul 24, 2022 at 6:14
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    \$\begingroup\$ The basic topology is correct. You could probably use much larger than 10 k resistors if you want. \$\endgroup\$
    – user57037
    Commented Jul 24, 2022 at 6:24
  • \$\begingroup\$ How does the larger resistor help? \$\endgroup\$
    – rlgjr562
    Commented Jul 24, 2022 at 18:08
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    \$\begingroup\$ @rlgjr562 It will reduce the amount of current flowing through it when the N-channel is turned on. This really only matters if efficiency is important. Increasing that resistance will also cause the P-Channel to turn off slower, so be aware of that. \$\endgroup\$ Commented Jul 25, 2022 at 15:57

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