The DS7505 low-voltage (1.7V to 3.7V) digital thermometer and thermostat provides 9-, 10-, 11-, or 12-bit digital temperature readings over a -55C to +125C range with 0.5C accuracy over a -0C to +70C range. A 9-bit resolution mode is software compatible with the LM75. Communication with the DS7505 is achieved through a simple 2-wire serial interface. Three address pins allow up to eight DS7505 devices to operate on the same 2-wire bus, which greatly simplifies distributed temperature-sensing applications. The DS7505 thermostat has a dedicated open-drain output (O.S.) and programmable fault tolerance, which allows the user to define the number of consecutive error conditions that must occur before O.S. is activated. There are two thermostatic operating modes that control thermostat operation based on user-defined trip points (TOS and THYST) that are stored in EEPROM registers.