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My goal is to design a circuit using MOSFETs that would switch 12V power to one of the two high-current loads, using high-side switching. Control is done by a 3.3V MCU. The reason for using MOSFETS is to keep the size down.

This is my current design. The problem is that there's a short period when both of the MOSFETs are on.

enter image description here

One obvious solution would be to separate the control of the circuits so that both could be turned off before switching between the loads. The downside being that the responsibility for keeping the loads from being turned on at the same time shifts to software.

I've looked into using gate drivers, but unless I'm missing something, there doesn't seem to be a driver for a pair of P-MOSFETS which is what I think I need to be using for high-side switching.

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    \$\begingroup\$ Useful search term: "Dead-Time" \$\endgroup\$
    – Tom Carpenter
    Commented Jul 21, 2020 at 8:42
  • \$\begingroup\$ you can switch high with n-chan, you just need a voltage of Vgs+v1 instead of v1. You can use a photovoltaic mosfet driver instead of an additional psu. \$\endgroup\$
    – dandavis
    Commented Jul 21, 2020 at 19:35

1 Answer 1

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Use something like this to split the gate drive signals to the N-channel MOSFETs: -

enter image description here

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