Stepper/dual DC motor drive with 4 external components

January 18, 2017 // By Graham Prophet
This low-voltage bipolar driver IC integrates PWM current control, overcurrent protection and extended voltage range. From Allegro MicroSystems, the A3916 low voltage bipolar IC is designed for PWM control of low-voltage stepper motors or dual DC motors using just four external components, and is capable of output currents up to 1A per channel and operating voltages from 2.7 to 15V.

The A3916 integrates all motor control circuitry including a fixed off-time PWM regulator that sets a peak current in the motor winding based on the selection of a low-value current-sense resistor. A single supply eliminates the need for an external low-dropout regulator, and the integrated charge pump requires only one external capacitor. Output diagnostics are provided by an active low fault output that notifies the user of a Thermal Shutdown (TSD) or overcurrent protection event.


The device is targeted at applications that run off single, Li-ion cell or three AA batteries, including office and industrial automation systems, point-of-sale equipment, 3D printers, medical, CCTV and the toy market. Two package options are offered: a low-profile 3 × 3 mm 16-terminal QFN (suffix ES) and a drop-in replacement for the A3916 in a low-profile 4 × 4 mm 20-terminal QFN (suffixes ES and -1). Both products have an exposed power tab for enhanced thermal dissipation.


Allegro MicroSystems;


Download a copy of the A3916 dual DMOS full-bridge motor driver data sheet.