Low noise single coil fan driver IC

Paul Boughton

Melexis’ MLX90297 is a 600mA single coil fan driver IC. Aimed at development of energy efficient cooling system designs, this latest device adds to the company’s portfolio of All-in-One single coil fan drivers, and is a further development of the MLX90287 device. It integrates a high sensitivity Hall Effect sensor with two powerful half bridge output stages.

In addition to the minimum speed setting incorporated into the MLX90287, the speed curve of MLX90297 can also be tuned through inclusion of just one extra resistor.

The soft start and soft switching mechanisms have been further refined to achieve industry-leading acoustic noise levels, as well as low vibration at higher speeds, without maximum motor torque being sacrificed.

The reduced driver resistance (RDSon) of the MLX90297, in combination with the built-in current limiting, allows application of this fan driver to fans with coil resistances substantially lower than 10Ohm. The electro-static discharge (ESD) performance has been further enhanced to achieve 9kV HBM.

The device is offered in a straight lead SOIC8 package. A DFN10 3mm x 3mm exposed pad package option is also available for very small fans and fans with motor currents up to 600mA.