Allegro Announces New Dual Full-Bridge Pwm Motor Driver

Allegro Announces New Dual Full-Bridge Pwm Motor Driver

Allegro MicroSystems, Inc. announces a new dual full-bridge pulse-width modulated (PWM) motor driver designed to drive both windings of a two-phase bipolar stepper motor. The device includes two H-bridges capable of continuous output currents of ±650 mA and operating voltages to 30 V. Motor winding current can be controlled by the internal fixed-frequency, pulse-width modulated (PWM), current-control circuitry. The peak load current limit is set by the user's selection of a reference voltage and current-sensing resistors.

Allegro MicroSystems, Inc. announces a new dual full-bridge pulse-width modulated (PWM) motor driver designed to drive both windings of a two-phase bipolar stepper motor. The device includes two H-bridges capable of continuous output currents of ±650 mA and operating voltages to 30 V. Motor winding current can be controlled by the internal fixed-frequency, pulse-width modulated (PWM), current-control circuitry. The peak load current limit is set by the user’s selection of a reference voltage and current-sensing resistors.

The fixed-frequency pulse duration is set by a user-selected external RC timing network. The capacitor in the RC timing network also determines a user selectable blanking window that prevents false triggering of the PWM current control circuitry during switching transitions.

To reduce on-chip power dissipation, the H-bridge power outputs have been optimized for low saturation voltages. The sink drivers feature Allegro’s patented Satlington™ output structure. The Satlington™ outputs combine the low voltage drop of a saturated transistor and the high peak current capability of a Darlington.