A3977KED PLCC-44 Stepper motor driver

The A3977 is a complete microstepping motor driver with built-in translator. It is designed to operate bipolar stepper motors in full-, half-, quarter-, and eighth-step modes, with output drive capability of 35V and ±2.5 A. The A3977 includes a fixed off-time current regulator that has the ability to operate in slow-, fast-, or mixed-decay modes. This current decay control scheme results in reduced audible motor noise, increased step accuracy, and reduced power dissipation. The translator is the key to the easy implementation of the A3977. By simply inputting one pulse on the STEP input the motor will take one step (full, half, quarter, or eighth depending on two logic inputs). There are no phase-sequence tables, high-frequency control lines, or complex interfaces to program. The A3977 interface is an ideal fit for applications where a complex µP is unavailable or over-burdened. Internal synchronous-rectification control circuitry is provided to improve power dissipation during PWM operation.
Internal circuit protection includes thermal shutdown with hysteresis, under-voltage lockout (UVLO) and crossover-current protection. Special power-up sequencing is not required.

* ±2.5 A, 35 V Output Rating
* Low rDS(on)Outputs, 0.45 OSource, 0.36 OSink Typical
* Automatic Current Decay Mode Detection/Selection
* 3.0 V to 5.5 V Logic Supply Voltage Range
* Mixed, Fast, and Slow Current Decay Modes
* Home Output
* Synchronous Rectification for Low Power Dissipation
* Internal UVLO and Thermal Shutdown Circuitry
* Crossover-Current Protection