Electronic – How to use a MOSFET driver directly to drive DC motors with PWM

3.3vdc motorflybackmosfet-driverpwm

I need to control a DC motor runs at 9v with PWM signal 3.3V enter image description here vpeak.

I found MOSFET driver noninverting MCP1401.
Can this MOSFET be used directly with a Back EMF diode (diode as usual across the motor terminals)?

The motor current rating is 200mA and voltage is 9V. the MCP1401 is 500mA
Is the above diagram correct?

Best Answer

There is nothing in the datasheet that indicates that the gate driver could be used to source DC, but the operation was never intended for such:

MOSFET drivers are high-speed, high-current device swhich are intended to source/sink high peak currents to charge/discharge the gate capacitance of external MOSFETs or IGBTs.

Source: http://ww1.microchip.com/downloads/en/DeviceDoc/20002052D.pdf

Mosfet gates are high impedance, and only need current while switching. Using the gate driver in a constant mode at high current could cause failure. There is nothing in the datasheet to indicate this (there are no DC specs) because the designers did not intend or test it for DC use.

I would use the MCP1402 to drive an h-bridge and use that to drive the motor.

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