I have a 12V DC motor that I plan to run in one direction with PWM input at 21A. However, in the other direction I want to drop the voltage to limit the speed. Ideally. the regulator would sit between the motor controller and the motor. The current draw is no more than 8A in this direction. What is a robust voltage regulation solution that can handle a nasty PWM input at relatively high current?
Alternatively, how could I limit the duty cycle of the PWM in one direction with hardware given the above conditions?