This draft illustrate a PWM module based on the driver of the motor controller we made earlier. We use a concept of a gate driver and 2 x HEXFET to create a Half H-Bridge. We will need 10V+ due to the gate driver, but we only need 1-3A on this one. I think it is realistic to have 8 channels, but if not we will reduce the numbers. PWM out will be anything from constant voltage to 0 duty. We will pulse on/off and use a 2nd frequency to pulse (regulate voltage) within the main pulse.
This targets solenoids with 12-48V and <3A.