DUAL DMOS FULL-BRIDGE MICROSTEPPING PWM MOTOR DRIVER

Designed for pulse-width modulated (PWM) current control of bipolar microstepping stepper motors, the A3972SB is capable of continuous output currents to ±1.5 A and operating voltages to 50 V. Internal fixed off-time PWM current-control timing circuitry can be programmed via a serial interface to operate in slow, fast, and mixed current-decay modes.

The desired load-current level is set via the serial port with two 6-bit linear DACs in conjunction with a reference voltage. The six bits of control allow maximum flexibility in torque control for a variety of step methods, from microstepping to full-step drive. Load current is set in 1.56 increments of the maximum value.

FEATURES

■ ±1.5 A, 50 V Continuous Output Rating

■ Low rDS(on) DMOS Output Drivers

■ Optimized Microstepping via 6-Bit Linear DACs

■ Programmable Mixed, Fast, and Slow Current-Decay Modes

■ 4 MHz Internal Oscillator for Digital Timing

■ Serial-Interface Controls Chip Functions

■ Synchronous Rectification for Low Power Dissipation

■ Internal UVLO and Thermal Shutdown Circuitry

■ Crossover-Current Protection

■ Precision 2 V Reference

■ Inputs Compatible with 3.3 V or 5 V Control Signals

■ Sleep and Idle Modes