CPC H02P 8/12 (2013.01) [G01R 19/16538 (2013.01); H02P 7/04 (2016.02); H02P 8/34 (2013.01); H03K 5/24 (2013.01); H03K 3/02337 (2013.01)] | 20 Claims |
8. A device adapted to be coupled to a stepper motor and operable to control the stepper motor, the device comprising:
a processing device having a first output adapted to be coupled to the stepper motor and a second output, the processing device configured to:
calculate a duty cycle of a current provided to a stepper motor; and
output, at the second output, a calculated duty cycle signal indicative of the calculation;
at least one register coupled to the processing device and configured to store a base duty cycle value of current provided to the stepper motor under a base load condition, and to store a reference duty cycle value;
a subtractor coupled to the processing device and to the at least one register, the subtractor configured to:
receive the calculated duty cycle signal; and
provide a subtractor signal responsive to a difference between the calculated duty cycle and the base duty cycle value; and
an error amplifier coupled to the subtractor and to the at least one register, the error amplifier configured to:
receive the subtractor signal;
compare the subtractor signal to the reference duty cycle value; and
provide an error signal responsive to the comparison;
wherein the processing device is further configured to adjust a peak current level of the current provided to the stepper motor responsive to the error signal.
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