Im working on a car seat that has a cool function. The blower blower motor has a logic board in it. It is supplied with 12 volts and a ground. The ground side is controlled by the logic board via a pwm ground signal. Can anyone recommened a low side drive that would work?
Can you share a photo of what you’re describing?
Do you know the amperage of the blower motor?
any suggestions based on the wiring diagram?
I had a hard time reading it, but here’s my take given my understanding…For an OEM seat blower with logic board, & PWM ground control, you have two practical paths:
DIY Build
This is likely your cleanest/fastest solution:
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MOSFET: IRLZ44N or IRFB4110PbF (this is just a guess, pick one sized ~2x the max current draw of the motor)
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Gate Driver: TC4427 or UCC27517
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Freewheeling Diode: MBR1045 Schottky
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Perfboard + connectors:
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Heat sink: Adding a small aluminum piece if the MOSFET doesn’t come with one might be a good idea to keep things cool
Wire it as: Motor Ground → Drain → Source → Chassis Ground, with the gate driven by your PWM source. The 12V feed stays constant.
Or, you could try to adapt a Pre-Made Module
If you want something closer to plug-and-play, look for:
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“PWM solenoid driver” or “PWM valve controller” modules on Amazon/AliExpress — these are more likely to be true low-side switches
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Infineon HITFET evaluation boards — automotive-qualified low-side smart switches, but you’ll need to source through distributors (DigiKey.com & Mouser.com are both excellent choices)
The main consideration will be the in-rush/max amp draw for the motor, which you will need to measure to determine and then pick a path above