Thermocouple

Wide range temperature sensing

With the Thermocouple Nanoshield you can read temperatures from -270ºC up to 1372ºC with a resolution of 0,25ºC, using a type K thermocouple probe (not included). This module uses the MAX31855 IC, which contains an SPI interface, internal temperature sensor (cold junction) and failure detection, such as open circuit and short circuit conditions on the thermocouple probe.

The circuit is powered directly by the internal 3.3V regulator from the Arduino board, and the SPI signals go through a level shifter that accepts 5V or 3.3V inputs. If you are not using an Arduino or if you don't have a 3.3V supply in your project, it's possible to install an optional regulator in the module, supporting voltages from 5V up to 12V.

Features:

  • Uses the MAX31855 IC from Maxim Semiconductor.
  • Temperature range from -270ºC to 1372ºC, with 0.25ºC resolution.
  • Internal temperature sensor ranging from -40ºC to 125ºC, with 0.0625ºC resolution.
  • 5V or 3.3V SPI interface.
  • 16 options for the chip select pin (/CS), configurable via solder jumpers (default is pin D8).
  • Thermocouple input filter for greater stability.
  • Works with any Type K thermocouple.

Thermocouple Nanoshield diagram

Thermocouple Nanoshield block diagram

Thermocouple Arduino Function
/CS D8 SPI chip select
SDO D12 SPI data output (MISO)
SCK D13 SPI clock
3V3 3V3 3.3V power supply input
VCC VCC 5V power supply input (optional)
VIN VIN External power supply input (optional)
GND GND Reference voltage (ground)
Pin description

Electrical specifications

  • Power supply: must be provided on the 3V3 pin, with a range from 3V to 3.6V (3.3V typical).

  • Current consumption: approximately 1,5mA.

  • Logic levels: the input pins /CS and SCK accept voltages of 5V or 3.3V. The SDO output pin has a logic level of 3.3V and it's 100% compatible with the logic levels accepted by the Arduino board.

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