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I built this simple MOSFET driver and it won't work.

The MOSFET used is AOD442. Supply+ is 24V. The load is a vacuum pump. The control signal is from a Raspberry Pi 4B. I took a few measurements and when I turn on the control signal I can see 12V on the gate pin as expected. However, the pump does not turn on. I connected the pump across the supply separately just to check if it works and it does. Completely stumped! Why won't this work?

enter image description here

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    \$\begingroup\$ So, the motor is connected between SUPPLY+ and OUT, yes? \$\endgroup\$
    – Andrew Morton
    Aug 25, 2021 at 14:27
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    \$\begingroup\$ @TonyStewartEE75 I think that says "COLL" (for collecter?) not coil. Is that what you were referring to? \$\endgroup\$
    – Simon Fitch
    Aug 25, 2021 at 14:33
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    \$\begingroup\$ What is the drain voltage when the MOSFET is "on", with its gate at 12V? (and with the pump connected, of course) \$\endgroup\$
    – Simon Fitch
    Aug 25, 2021 at 14:34
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    \$\begingroup\$ I made a really really really stupid mistake. I connected the pump between MOUT and GNDPWR instead of SUPPLY+ and MOUT. It works now. \$\endgroup\$
    – user3418620
    Aug 25, 2021 at 14:46
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    \$\begingroup\$ @electrophile I was concerned when I asked about the connection because I saw two GND terminals on the connector when it only needs one, but it needs two SUPPLY+ terminals. \$\endgroup\$
    – Andrew Morton
    Aug 25, 2021 at 14:52

1 Answer 1

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I made a stupid error. I kept connecting the coil between OUT and GNDPWR when it should have been SUPPLY+ and MOUT. All is well now. The schematic works fine.

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