Date: 26/11/2008

Smart Motor Controller for low voltage cooling fans

AH5792 from Diodes Incorporated provides all the functionality required for driving low power single coil brushless DC fans and motors. The AH5792 integrates a Hall sensor and amplifier, digital control circuitry and a full bridge output driver

With its bi-directional, H-bridge output stage, the AH5792 suits single-phase full wave brushless DC motor control, by offering a pair of push-pull output drivers to source and sink current. The device operating voltage range of 1.8V to 5V also caters for low operating voltage miniature DC fans requiring low voltage start-up.

To protect motor windings from damage, the new motor controller includes integrated locked rotor detection and automatic self restart functions, which serve to shutdown the output driver in the event of a locked rotor and then restart the motor when the rotor is freed. In addition, a frequency generator output provides users with tachometer-like feedback for external speed monitoring.

The AH5792 has an operating temperature range of -40C to 100degC and is fully RoHS complaint with Green molding compound.