Space-saving Smart Motor Controller

Date: 1/2/2010

Space-saving Smart Motor Controller

Diodes Incorporated has launched an all-in-one motor controller IC for single-coil low-power brushless DC fans and motors.

Housed in a SOT89-5L package and designed to substantially reduce component counts and PCB area, the AH5798 motor controller provides all the drive, protection and interface functionality necessary in small fan and motor applications.

Integrating a full-bridge driver featuring soft switching, the AH5798 controller requires no external driver components and yet supports average source and sink currents up to 300mA. The device’s soft switching operation makes it particularly suitable for low noise applications. Further space saving comes from the built-in Hall sensor and amplifier.

The controller’s locked rotor detection and self restart functions help protect the coil from over-heating or burning out and initiate automatic restart once the locked rotor is released. The AH5798 also includes a tachometer open-drain output to make the device easier to interface for external status and speed monitoring.

The AH5798 operates at a low voltage of between 1.8V to 5.5V, which contrasts with its high ambient operating temperature rating of –40ºC to +105ºC.