The ADT6501/ADT6502/ADT6503/ADT6504 are trip point temperature switches available in a 5-lead SOT-23 package. Each part contains an internal band gap temperature sensor for local temperature sensing. When the temperature crosses the trip point setting， the logic output is activated. The ADT6501/ ADT6503 logic output is active low and open-drain. The ADT6502/ADT6504 logic output is active high and push-pull. The temperature is digitized to a resolution of 0.125°C （11-bit）。 The factory trip point settings are 10°C apart starting from ?45°C to +15°C for the cold threshold models and from +35°C to +115°C for the hot threshold models. These devices require no external components and typically consume 30 μA supply current. Hysteresis is pin-selectable at 2°C and 10°C. The temperature switch is specified to operate over the supply range of 2.7 V to 5.5 V. The ADT6501 and ADT6502 are used for monitoring temperatures from +35°C to +115°C only. Therefore， the logic output pin becomes active when the temperature goes higher than the selected trip point temperature. The ADT6503 and ADT6504 are used for monitoring temperatures from ?45°C to +15°C only. Therefore， the logic output pin becomes active when the temperature goes lower than the selected trip point temperature.