The A3988 is a quad DMOS full-bridge driver capable of driving up to two stepper motors or four dc motors. Each full-bridge output is rated up to 1.2 A and 36 V. The A3988 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, and dc motors in forward, reverse, and coast modes. The PWM current regulator uses the Allegro patented mixed decay mode for reduced audible motor noise, increased step accuracy, and reduced power dissipation. |