The DS75 digital thermometer and thermostat provides 9, 10, 11, or 12-bit digital temperature readings over a -55°C to +125°C range with ±2°C accuracy over a -25°C to +100°C range. At power-up, the DS75 defaults to 9-bit resolution for software compatibility with the LM75. Communication with the DS75 is achieved via a simple 2–wire serial interface. Three address pins allow up to eight DS75 devices to operate on the same 2–wire bus, which greatly simplifies distributed temperature sensing applications.The DS75 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 userdefined trip-points (TOS and THYST).A block diagram of the DS75 is shown in Figure 1 and detailed pin descriptions are given in Table 2.