I²C Temperature Sensor as a Sealed External Temperature Probe

Below are a few suggested options:

Option 1

The MCP9600 demo board has a thermocouple probe and is a good plug and play solution. The MCP9600 supports I²C and max accuracy of ± 1.5 degrees with a typical ± 0.5 degrees. You can use a thermocouple wire to whichever length is desired rather than using the probe provided with the board.

Option 2

Use a tiny PCB for the MCP9808 to put the probe on and use four copper wires (one meter long each) for VDD/VSS/SCL/SDA. The advantage is that you will have better accuracy - 0.5C max accuracy. Note that the VDD line will be long, you may need to add an RC filter on the VDD at the sensor to filter out noise during data communication.

Option 3

Make a small PCB with the following components:

  • LDO - MCP1703A/MCP1755
  • PIC® MCU - PIC12F1xxx with UART and I²C
  • MCP9808 takes the measurements and sends them via UART. This way, the noise problem can be prevented and only three wires are used.
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