Microchip has announced the new MCP990X series of temperature sensor ICs with System Management Bus (SMBus) interface, designed to monitor up to four channels in cold surroundings. With a rated accuracy of ±1°C for internal and external diode temperatures from -40 to +65°C, these ICs give designers a low-cost and especially versatile option when accurate measurements are required at relatively low temperatures.
 
The attractive features of the MCP990X series include thermal diode measurements with resistance error correction to compensate for voltage drops over connectors and long PCB tracks, enabling accurate readout at distances up to approximately 50 cm from the IC. Any injected system noise is minimized by a tracking filter that adapts to the sampling rate.
 
The packages of the new sensor ICs are very compact – the MCP9902 dual-channel temperature sensor has a footprint of just 2x2 mm, while the MCP9903 triple and MCP9904 quad temperature sensor ICs are slightly larger at 3x3 mm.