Totem Pole Output VS a FET Switch

A project log for OpAmp Buck Regulator

A quad OpAmp Makes a Buck Regulator

aaron-lagerAaron Lager 04/23/2023 at 17:070 Comments

While doing a few final checks, I thought I'd check the currents from the opamp.

Whoa!  The current is going plus and minus!

This makes total sense, the output of the opamp is designed to sink AND source current.  We only want it to source current.  Adding  a diode to the output of the opamp will solve that.

Much better, current is only going in one direction now.

And our new kiCAD drawing: