2919

A2919 Dual Full-Bridge PWM Motor Driver Features and Benefits ▪ 750 mA continuous output current ▪ 45 V output sustaining voltage ▪ Internal clamp diodes ▪ Internal PWM current control ▪ Low output saturation voltage ▪ Internal thermal shutdown circuitry ▪ Half- or quarter-step operation of bipolar stepper motors Package: 24-pin SOIC with exposed thermal tabs (suffix LB) Description The A2919 motor driver is designed to drive both windings of a bipolar stepper motor or bidirectionally control two DC motors. Both bridges are capable of sustaining 45 V and include internal pulse width modulation (PWM) control of the output current to 750 mA. The outputs have been optimized for a low output-saturation voltage drop (less than 1.8 V total source plus sink at 500 mA). For PWM current control, the maximum output current is determined by the user’s selection of a reference voltage and sensing resistor. Two logic-level inputs select output current limits of 0%, 41%, 67%, or 100% of the maximum level. A PHASE input to each bridge determines load current direction. The bridges include both ground clamp and flyback diodes for protection against inductive transients. Internally generated delays prevent crossover currents when switching current direction. Special power-up sequencing is not required.Thermal protection circuitry disables the outputs if the chip temperature exceeds safe operating limits. Not to scale Continued on the next page… I 01 13 I1 12 PWM Control Circuitry Chann...