A4986

A4986 DMOS Dual Full-Bridge PWM Motor Driver with Overcurrent Protection FEATURES AND BENEFITS ▪ Low RDS(ON) outputs ▪ Internal mixed current decay mode ▪ Synchronous rectification for low power dissipation ▪ Internal UVLO ▪ Crossover-current protection ▪ 3.3 and 5 V compatible logic supply ▪ Thin profile QFN and TSSOP packages ▪ Thermal shutdown circuitry ▪ Short-to-ground protection ▪ Shorted load protection ▪ Low current Sleep mode, < 10 µA PACKAGES: 24-contact QFN 4 mm × 4 mm × 0.75 mm (ES package) Approximate footprint 24-pin TSSOP with exposed thermal pad (LP Package) DESCRIPTION The A4986 is a dual DMOS full-bridge stepper motor driver with parallel input communication and overcurrent protection. Each full-bridge output is rated up to 35 V and ±2 A. The A4986 includes fixed off-time pulse width modulation (PWM) current regulators, along with 2-bit nonlinear DACs (digital-to-analog converters) that allow stepper motors to be controlled in full, half, and quarter steps. The PWM current regulator uses the Allegro™ patented mixed decay mode for reduced audible motor noise, increased step accuracy, and reduced power dissipation. Internal synchronous rectification control circuitry is provided to improve power dissipation during PWM operation. The outputs are protected from shorted load and short-toground events, which protect the driver and associated circuitry from thermal damage or flare-ups. Other protection features include thermal shutdown with hysteresis, underv...