The MAX6665 is a fully integrated thermal switch with an internal power transistor for driving a cooling fan rated up to 24V and 250mA. When the MAX6665's temperature rises above a factory-programmed threshold, the FANOUT pin becomes active and powers the fan. The MAX6665 is available with factory-programmed fan activation threshold temperatures from +40C to +70C in 5C increments. Accuracy of the fan activation trip point is 1C (typ) and 3C (max). The trip point's hysteresis is pin selectable to 1C, 4C, or 8C. Two opendrain logic outputs indicate overtemperature conditions: WARN is activated when the temperature is 15C above the fan activation threshold, and OT is activated when the temperature is 30C above the threshold. These features can be used to safely power down systems that are overheated.