3961

3961 DUAL FULL-BRIDGE PWM MOTOR DRIVER 3961 Designed for pulse-width modulated (PWM) current control of bipolar stepper motors, the A3961S— is capable of continuous output currents to ±800 mA and operating voltages to 45 V. Internal fixed off-time PWM current-control circuitry can be used to regulate the maximum load current to a desired value. An internal precision voltage reference is provided to improve motor peak current control accuracy. The peak load current limit is set by the user’s selection of an external resistor divider and current-sensing resistors. The fixed off-time pulse duration is set by user-selected external RC timing networks. 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. This eliminates the need for two external RC filter networks on the current-sensing comparator inputs. Data Sheet 29319.26 DUAL FULL-BRIDGE PWM MOTOR DRIVER 1 OUT 1B 24 23 OUT 2B E2 Note the A3961SB (DIP) and the A3961SLB (SOIC) are electrically identical and share a common terminal number assignment. ABSOLUTE MAXIMUM RATINGS Load Supply Voltage, VBB . . . . . . . . . . 45 V Output Current, IOUT . . . . . . . . . . ±800 mA* Logic Supply Voltage, VCC . . . . . . . . . 7.0 V Logic Input Voltage Range, VIN . . . . . . . . . . . -0.3 V to VCC + 0.3 V Sense Voltage, VSENSE . . . . . . . . . . . . 1.0 V Reference Output Current, IREF OUT . . . . . ...