TC642BEOA Datasheet PDF - Microchip

●The TC642BEOA is a PWM Fan Speed Controllers with fan restart and FanSense™ technology for fault detection. This device is switch mode, fan speed controller that incorporates a new fan auto-restart function. Temperature-proportional speed control is accomplished using pulse width modulation. A thermistor connected to the VIN input supplies the required control voltage of 1.2 to 2.6V typical for 0 to 100% PWM duty cycle. Minimum fan speed is set by a simple resistor divider on the VMIN input. An integrated start-up timer ensures reliable motor start-up at turn-ON, coming out of shutdown mode or following a transient fault. A logic-low applied to VMIN causes fan shutdown. In normal fan operation, a pulse train is present at SENSE (pin 5). A missing-pulse detector monitors this pin during fan operation. A stalled, open or unconnected fan causes the TC642B device to turn the VOUT output on full. If the fault persists, the FAULT output goes low.

● Temperature-proportional fan speed for acoustic noise reduction and longer fan life

● Efficient PWM fan drive

● FanSense™ Fault detection circuit protects against fan failure and aids system testing

● Shutdown mode for green systems

● Supports NTC/PTC thermistors

● Over-temperature indication

● Fan auto-restart