STEPPER MOTOR CONTROL CIRCUIT

摘要

A stepper motor control circuit includes a waveform generator circuit which produces two identical substantially stepless symmetrical waveforms (preferably of triangular configuration) at a frequency which can be varied on demand. Each waveform is used as a current demand signal for a pulse width modulator with a push-pull output stage controlling current in the motor windings . The pulse width modulator runs at a fixed frequency an order of magnitude higher than the maximum required stepping frequency. A current sensing resistor provides a feedback signal which is fed back to input of the modulator to balance the demand signal.