Multi-channel temperature sensors deliver greater accuracy

Microchip has introduced the MCP990X family of System Management Bus (SMBus) temperature sensor ICs for monitoring up to four channels in cold, outdoor and industrial low-temperature applications ranging from freezers and refrigerators to base stations and remote radio units. With ±1C maximum accuracy for both external and internal diode temperatures from -40C to +65C, the ICs provide a low-cost, highly flexible solution where precision is needed at lower temperatures. Advanced features of the MCP990X family include remote diode temperature measurement with resistance error correction that compensates for voltage drops from connectors and long board traces, enabling accurate readings of up to 20 inches away from the IC. Injected system noise from components such as DC-DC converters and backlight inverters is also minimised with a sample-frequency hopping filter, allowing for easier placement and routing. The combination of these features with options for dual-, triple- and quad-channel temperature monitoring provides for a wider range of measurement opportunities for an entire system with a single IC. Compact package options that take up less silicon space on the PCB and allow for smaller system solutions and better product design for temperature-critical applications include a 2mm x 2mm footprint for the MCP9902 dual-channel temperature sensor. The IC is the smallest temperature sensor in Microchip’s portfolio and 33 percent smaller than the company’s previous generation dual temperature sensor. Additionally, a 3x3mm footprint package is available for the MCP9903 triple and MCP9904 quad temperature sensors. Enabling development with the MCP9902 low-temperature sensor, Microchip has also introduced the MCP9902 Evaluation Board.