LM317 vregs using MOSFETs

[Jeff Birkle]

Hello,
I'm wondering why no one uses MOSFETs instead of a Transistors for high amp, voltage regulation circuits?
Or am I just not finding it?

 

[crutschow]

The problem is that MOSFETs generally require a high gate-source voltage to turn on which increases the minimum voltage drop across the regulator. For many regulator applications you want to minimize the drop to reduce power dissipation.

 

[ericgibbs]

Hello,
I'm wondering why no one uses MOSFETs instead of a Transistors for high amp, voltage regulation circuits?
Or am I just not finding it?

hi,
It can be done using a P MOSFET say a IRF7404 which has very low gate turn on voltage. It would require the usual large heatsink.

 

[MikeMl]

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