Adafruit Thermocouple Amplifier MAX31855 breakout board (MAX6675 upgrade)

Thermocouples demand precision, needing an effective amplifier and cold-compensation. The MAX31855K offers an all-in-one solution, simplifying integration with any microcontroller—even those lacking analog inputs. This versatile breakout board includes the advanced MAX31855K chip, a 3.3V regulator, 10uF bypass capacitors, and level-shifting circuitry—fully assembled and tested for reliability.

Outfitted with a 2-pin terminal block for thermocouple connections and a pin header compatible with breadboards or perfboards, this board seamlessly pairs with our 1m K-type thermocouple. The updated module now uses the MAX31855K chip instead of the discontinued MAX6675, offering a broader temperature measurement range. Note, existing MAX6675 designs require adjustments for compatibility.

With compatibility for only K type thermocouples, the MAX31855K supports a measurement range from -200°C to +1350°C in 0.25-degree increments, though K thermocouples typically have an accuracy range of ±2°C to ±6°C. The board features internal temperature reading, works with 3.3 to 5V power supplies, and is SPI data output capable using any 3 digital I/O pins. Our comprehensive tutorial covers both CircuitPython and Arduino libraries, with wiring diagrams and example code to simplify integration.