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