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I've got a servo setup with an Arduino, and I'm looking for a good way to switch the power to the servo on and off. I've come up with the below circuit: Power circuit

My intention behind the circuit is to set the MCU Pwr Signal to HIGH when I want the servo to receive power. Then, I'll send the signal through the MCU PWM to the Servo signal connection to control the servo. When I want to disable the power to the servo, I'll set the MCU Pwr Signal to LOW.

My question is, will this work? Have I got my circuit correct?

Thanks in advance!

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Yes, that will work, assuming that the magnitude of the threshold voltage VGS(th) of the P-MOSFET is low enough. The gate voltage will be around -5.8 V = -6 V + ~200mV: the (relative) supply voltage plus the collector-emitter saturation voltage VCE(sat) of the NPN BJT.

If you have a 5 V microcontroller, you could probably get away with removing the BJT and connecting R2 straight to the R1 - gate node. As few P-MOSFETs conduct at -1 V, you could just connect the gate via a protection resistor to the (5 V capable) microcontroller pin.

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