The A3968SA and A3968SLB are designed to bidirectionally control two dc motors. Each 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. Except for package style and pinout, the two devices are identical. 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 SatlingtonTM output structure. The Satlington outputs combine the low voltage drop of a saturated transistor and the high peak current capability of a Darlington.