+ A3966 Dual Full-Bridge PWM Motor Driver Features and Benefits Description 650 mA continuous output current The A3966 is designed to drive both windings of a two-phase 30 V output voltage rating bipolar stepper motor. The device includes two full-bridges Internal fixed-frequency PWM current control capable of continuous output currents of 650 mA and operating Satlington sink drivers voltages to 30 V. Motor winding current can be controlled by User-selectable blanking window the internal fixed-frequency, pulse-width modulated (PWM), Internal ground-clamp and flyback diodes current-control circuitry. The peak load current limit is set Internal thermal-shutdown circuitry by user selection of a reference voltage and current-sensing Crossover-current protection and UVLO protection 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 full-bridge power Package: 16 pin SOICW (suffix LB) outputs have been optimized for low saturation voltages. The sink drivers feature the Allegro 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. For each bridge, a PHASE input controls load-current polarity by selecting the appropriate source and sink driver pair. For Not to scale Continued on the next page Typical Application 16 1 V BB PHASE PHASE 2 15 2 1 ENABLE ENABLE 3 14 1 2 LOGIC LOGIC 4 13 0.5 0.5 5 12 +5 V 6 11 +24 V V BB +5 V 7 V 10 CC V 8 RC 9 REF 47 F Dwg. EP-047-4A 29319.25K 10 k 39 k 56 k 680 pFA3966 Dual Full-Bridge PWM Motor Driver Description (continued) each bridge, an ENABLE input, when held high, disables the output The A3966 is supplied in a 16-lead plastic wide SOIC with two pins drivers. Special power-up sequencing is not required. Internal circuit internally fused to the die pad for enhanced thermal dissipation. These protection includes thermal shutdown with hysteresis, ground-clamp pins are at ground potential and need no electrical isolation. The and flyback diodes, and crossover-current protection. device is lead (Pb) free, with 100% matte tin leadframe plating. Selection Guide Ambient Temperature Range Part Number Packing (C) A3966SLBTRT 1000 pieces / reel 20 to 85 Absolute Maximum Ratings Characteristic Symbol Notes Rating Units Load Supply Voltage V 30 V BB Logic Supply Voltage V 7.0 V CC Input Voltage V 0.3 to V + 0.3 V IN CC Sense Voltage V 1.0 V S Output current rating may be limited by duty Peak 750 mA cycle, ambient temperature, and heat sinking. Output Current* I OUT Under any set of conditions, do not exceed the Continuous 650 mA specified current rating or T (max) J T = 25C per SEMI G42-88 Specification, Thermal Test A Package Power Dissipation P Board Standardization for Measuring Junction-to-Ambient 1.87 W D Thermal Resistance of Semiconductor Packages. Operating Ambient Temperature T Range S 20 to 85 C A Maximum Junction Temperature T (max) 150 C J Storage Temperature T 55 to 150 C stg Pin-out Diagram OUT 1 16 OUT 2A 1A V BB PHASE PHASE 2 15 2 1 ENABLE ENABLE 14 1 3 2 LOGIC LOGIC GROUND 4 13 GROUND SENSE 5 12 SENSE 1 2 OUT 6 11 OUT 1B 2B V LOAD BB LOGIC 7 V 10 SUPPLY CC SUPPLY REFERENCE V RC RC 8 9 REF Allegro MicroSystems, LLC 2 115 Northeast Cutoff Worcester, Massachusetts 01615-0036 U.S.A. 1.508.853.5000 www.allegromicro.com