[Afroman] contacted us to share his new video on the LM317. The humble LM317 adjustable voltage regulator is everywhere. From wifi routers, to high spec lab equipment. Given a noisy input and a ...

His solution is to add a P channel MOSFET which only allows power to flow when the polarity of the source voltage is correct. The schematic above shows the P-FET on the high side of the circuit.