The MAX6511/MAX6512/MAX6513 are fully integrated, remote temperature switches that use an external P-N junction (typically a diode-connected transistor) as the sensing element to measure the remote temperature. These devices assert a logic signal when the temperature crosses a factory-programmed threshold. Available trip thresholds are from +45C to +125C in 10C increments. Accuracy is within 3C (TA = -5C to +55C) or 5C (TA = -40C to +85C). Hysteresis is pin selectable to 5C or 10C. The MAX6511 has an active-low CMOS output and the MAX6513 has an active-high CMOS output. The MAX6512 has an open-drain output. The output is asserted when the temperature exceeds the threshold value. The active-low open-drain output is intended to interface with a microprocessor (P) reset or interrupt input. The active-high CMOS output can directly drive a power FET to control a cooling fan. The MAX6511/MAX6512/MAX6513 operate from a +3.0V to +5.5V supply and typically consume 400A of supply current. They are available in the small 6-pin SOT23. The MAX6513 is also available in a 6-pin leadfree TDFN package.