Hi there
The purpose of this schematic is to control a DC motor that runs at 8V max. That is why I chose 4 N-channel mosfets in the H bridge. P-channels would not fully activate at voltages above -10Vgs but the N-channels can handle 18V at the gate.
The 5v switches represent an Arduino's digital output pins. One to turn forward, one for reverse. To prevent a failure scenario where both pins are HIGH I added a transistor that prevents current from flowing through the optocoupler on the second half bridge.
Does this circuit make sense? I'm not an electronics engineer, just a hobbyist and have doubts about how effective the gate driving circuit is of the mosfets.
Thanks!
Good one. I haven´t considered that. The 7818 will only deliver current for very short bursts but perhaps that already is too much. I'll look into the PWM solution.