I am using a DRV8432 to drive a bipolar stepper motor. The application requires that the motor move at an overall rate of 75 degrees in 50 ms, stop and then return. With a stepper motor that moves 1.8 degrees per step this means I need to make a step every 1.2 ms. I can accomplish this with a 1 ms wide step using 32 volts as a supply. I have added a current sense and a chopper circuit in an attempt to control the current. The big problem I am seeing is what to do when I am not moving the entire 75 degrees...what do I need to do to only step one or two steps when necessary. I am experiencing not only high current issues but BEMF issues also. Should I be using a lower voltage to drive the stepper when I need to only move a few steps?
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