Using a 3.3V (max. 8 mA) output pin off an Intel Galileo development board, I need to turn on and off a 18V DC motor. Is it better to use a JFET or MOSFET transistor?

  • 1
    \$\begingroup\$ What are you metrics for "better"? \$\endgroup\$
    – PlasmaHH
    Aug 10, 2015 at 14:46
  • \$\begingroup\$ You can as well use 2 BJTs, connected as a Sziklai pair. 3.3V is a little low for driving a MOSFET; you'll need to use one that has low Rds at this gate voltage. \$\endgroup\$
    – ilkhd
    Aug 10, 2015 at 17:56

1 Answer 1


I doubt that a JFET will be able to adequately control a motor without significant power losses due to it's likely high on resistance. MOSFETs, on the other hand, are extensively used for controlling DC motors and power-hungry loads.

The best JFETs I've seen might just about get as low as a few ohms whereas I've seen MOSFETs that are that value divided by 1000. Also, JFETs tend not to be rated at voltages in excess of 30V.

A JFET, as a generalism, is not suited for motor power control.


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