Standalone driver rolls for small BLDC motors

Freescale Semiconductor's standalone MC34929 is suited to driving small three-phase brushless DC (BLDC) motors in consumer, portable and office equipment.

The MC34929, working from an 8-28V supply, provides up to 1A continuous. Designed with a built-in three-phase Hall-effect sensor interface and its supply, the MC34929 directs BLDC motors autonomously from a pushbutton or switch interface. Alternatively, users have provision for control by an external MCU such as the company's 8bit MC9S08QG8CDTE MCU. The chip's state machine accommodates several modes of operation, including clockwise, counterclockwise, run/stop, brake, variable speed and torque current limit.

The MC34929 includes built-in stall detection and protection circuitry, logic level control and various configuration and communication features for active monitoring of operation and increased reliability.

The MC34929, in a 4-by-4mm QFN package, is priced at $1.42 each in 10,000 pieces. Evaluation boards are available for a suggested resale price of $90. The KIT34929EGEVBE development tool incorporates digital I/O, making it easy to use with an MCU in a closed-loop motor control system.

- Vince Biancomano
eeProductCenter