Dual H-Bridge Gate Driver With Microstepping Translator

Allegro’s A3986 is a dual H-bridge gate driver with integrated microstepping translator to drive a wide range of medium to high-power bipolar stepper motors. Supply voltages range from 12 V to 50 V, and step modes are full, half, quarter and sixteenth step. Key features of the A3986 include simple two-wire step and direction interface, synchronous rectification control for lower power dissipation, automatic mixed-mode current decay control for quiet operation, large supply voltage range (12 to 50 V), and small 38-lead TSSOP package. The A3986 fills a market need for low-cost stepper drivers above the range of IC solutions that are limited to 2-3 A. Most of the market uses low-performance unipolar drivers for these applications. The A3986 provides a more efficient bipolar solution with minimal external components. Full-step to sixteenth-step microstepping control reduces system vibration and improves positioning accuracy.