Microchip Technology Inc.’s MCP9800/1/2/3 family of digital temperature sensors converts temperatures between -55°C and +125°C to a digital word. They provide an accuracy of ±1°C （maximum） from -10°C to +85°C. The MCP9800/1/2/3 family comes with user-programmable registers that provide flexibility for temperature sensing applications. The register settings allow user-selectable 9-bit to 12-bit temperature measurement resolution， configuration of the power-saving Shutdown and One-shot （single conversion on command while in Shutdown） modes and the specification of both temperature alert output and hysteresis limits. When the temperature changes beyond the specified limits， the MCP9800/1/2/3 outputs an alert signal. The user has the option of setting the alert output signal polarity as an active-low or active-high comparator output for thermostat operation， or as temperature event interrupt output for microprocessor-based systems. This sensor has an industry standard 2-wire， I2C?/ SMBus compatible serial interface， allowing up to eight devices to be controlled in a single serial bus. These features make the MCP9800/1/2/3 ideal for sophisticated multi-zone temperature-monitoring applications.