Driving a servo with MOSFET

Build a small battery powered device containing a servo. I would like to be able to turn off the servo to save battery life. I have read previously that MOSFETs can be used to do this, but I am having trouble finding example circuits that are detailed enough (missing resistor values with no way to calculate them) and to be honest Iam not too sure what sort of circuit I am looking for (I have
Driving a servo with MOSFET - schematic

never used any FETs before). Can someone please give me a nudge in the right direction If you want practical guidance, including part selection, look at some of the speed control projects for R/C systems which have been published - preferably a recent one. A FET that can run the drive motor should have little trouble with a servo. One thing to think about is if you could get away with using an N-channel device to switch the low side as those are fundamentally better than the P-channel devices. However, the brushless motor controllers that are all over the place today use both, so you could pick a P-channel device and drive circuit from there for high side switching. Chris Stratton Aug 1 `12 at 14:56

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