I am using the DRV8801 to control some 24V DC Brushed motors. I am supplying the motors with 24 volts on the VMM pin, and 5 volts on the VDD pin. I am setting BRAKE to low (no braking).
What I am seeing is that when I send it a 0 on the PWM input, the OUT+ pin has 0 volts being sent, but the OUT- pin has 12 volts on it. Doesn’t seem right. Can someone explain?
Also, when I tie the BRAKE pin to VCC, the controller behaves more as expected - a 0 PWM gives 0 volts on both OUT+ and OUT-.
My second question has to do with the BRAKE pin. Can someone give me a sense of how much braking it will brake when it brakes? The reason I thought I should set it to low (no braking) is that I need to fairly rapidly change motor speeds (almost every half second). The wheels seem to slow down enough when power is removed that I didn’t think I needed additional braking, and it seemed like it might be better able to transition between speeds if it didn’t brake. But maybe not - I need to do further testing.
In any case, it doesn’t seem like power should be applied to OUT- when the requested speed is 0, regardless of the BRAKE setting.