Date: 13/05/2012

Programmable stepper motor driver chip from Allegro for better programmability and diagnostics

Allegro MicroSystems has announced the programmable stepper motor driver IC A4979 with improved programmability and diagnostics. The A4979 is a flexible micro-stepping motor driver with built-in translator for easy operation. This single chip solution is designed to operate bipolar stepper motors in full-, half-, quarter- and sixteenth-step modes. The device can operate up to 50 V and 1.5 A. The chip is suitable for office automation, industrial and consumer markets.

The A4979 can be controlled by simple step and direction inputs, or through the SPI compatible serial interface. The integrated features and diagnostic read back are programmed through the serial port.

Circuit protection includes cross conduction when switching between high side and low-side drives. The outputs are protected from short circuits. Mixed decay is a key feature integrated within the device to improve low load current accuracy. Other protection includes stall detection and hot and cold thermal warnings, over temperature shutdown, and under voltage lockout.

The device is available in a 28-pin TSSOP package (suffix LP) with exposed pad for enhanced thermal dissipation.