01-10-2025 | Microchip Technology | Semiconductors
With the introduction of the MCP9604 integrated thermocouple conditioning IC, Microchip Technology has overcome a thermal measurement and integration barrier by delivering the first single-chip, four-channel I2C thermocouple conditioning IC. This device delivers up to ±1.5C accuracy, offering an alternative to discrete and multichip thermocouple conditioning solutions that can introduce errors and add system design complexity.
"For more than two centuries, the thermocouple has been a critical tool for measuring extremely high temperatures, but the necessary precision and accuracy could not be achieved with the level of integration and cost-effectiveness that is required for today's demanding production-line applications," said Keith Pazul, vice president of Microchip's mixed-signal linear business unit. "Our device now delivers a combination of precision, integration and cost-effectiveness, helping reduce the need for as many as 15 discrete components and associated system design challenges."
The device achieves its advanced measurement accuracy at four thermocouple locations by employing higher-order NIST ITS-90 equations, rather than the single-order linear approximations commonly found in analogue amplifier designs. For example, it achieves ninth-order accuracy with K-type thermocouples, all in one integrated chip that contains the ADCs, cold junction compensation temperature sensors, amplifiers, and other components required for the signal chain, temperature measurement, and math engine.
Removing the necessity for external components simplifies PCB design, reduces BoM costs, and can help eradicate the weeks of costly, time-consuming and complex unit-by-unit in-line validation and calibration that discrete solutions need in the thermocouple measurement signal chain before they can begin reporting data to the host system.
The device also offers flexibility and versatility by supporting the eight most common thermocouple types, including the J option and the K option for operating at temperatures as low as -200C. In addition to supporting a wide temperature range of -200C to +1372C across various industrial applications, it also facilitates I2C communication, enabling easy integration with MCUs and other digital systems.
The MCP9604 builds on the release of the company's single-channel thermocouple conditioning IC, the first all-in-one device to deliver up to ± 1.5°C accuracy. The core competencies that made this device possible have paved the way for its four-channel single-chip MCP9604 device, which delivers digital temperature readings with industry-high accuracy levels for an I2C thermocouple conditioning device.
The MCP9604 device is supported by the Microchip EV19L27A evaluation board. It can connect to and read information from as many as four thermocouples and includes a MCU that acts as a host system for receiving this information and plotting the selected thermocouple. The evaluation board also includes free software that can be downloaded from either the MCP9604 or EVB web pages.
