Variable speed is adjusted by varying the duty cycle to the PWM control input pin. Minimum RPM is programmable via a resistor divider to Vref. The analog control pin can be used to interface with a thermistor when the PWM input control is not needed. Soft switching reduces audible noise. Current limit, locked rotor and thermal protections are also provided. The 40V MOS output predrivers can source or sink 100mA.