Description

The A3977 is a complete microstepping motor driver, with builtin translator. It is designed to operate bipolar stepper motors in full-, half-, quarter-, and eighth-step modes, with output drive capability of 35 V 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.

Features and Benefits

▪ ±2.5 A, 35 V output rating

▪ Low rDS(on) outputs, 0.45 Ω source, 0.36 Ω sink typical

▪ Automatic current decay mode detection/selection

▪ 3.0 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