Microchip TC648BEOA, BLDC Motor Driver IC 8-Pin, SOIC [TC648BEOA]; 649-553

The Microchip Switch mode fan speed controller which incorporates a new fan auto restart function. Temperature proportional speed control is accomplished using pulse width modulation. A thermistor (or other voltage output temperature sensor) connected to the VIN input supplies the required control voltage of 1.20V to 2.60V (typical) for 0% to 100% PWM duty cycle. The auto-shutdown speed is set by a simple resistor divider on the VAS input. An integrated Start-Up Timer ensures reliable fan motor start-up at turn-on, coming out of shutdown mode, auto-shutdown mode, or following a transient fault.

Over Temperature Indication

Efficient PWM Drive

Automatic Shutdown Mode for Green Systems

3.0 V to 5.5 V Supply Range

Supports Low Cost NTC and PTC Thermistors