Table of Contents

MCP960X/MCP9600/MCP9601 - device family of cold-junction compensated thermocouple to digital converter

The MCP960X device family is an I2C interface cold-junction compensated thermocouple to digital converter. Supported thermocouple types (designated by NIST ITS-90) are: K, J, T, N, S, E, B and R. The MCP9600/01 converts the thermocouple EMF to degree Celsius with integrated cold-junction compensation.

Note: Default thermocouple type is K

Sensor Image

Illustration of wiring from a Raspberry Pi device

Documentation

MCP960X datasheet

Usage

Important: make sure you properly setup the I2C pins especially for ESP32 before creating the I2cDevice, make sure you install the nanoFramework.Hardware.ESP32 nuget:

//////////////////////////////////////////////////////////////////////
// when connecting to an ESP32 device, need to configure the I2C GPIOs
// used for the bus
Configuration.SetPinFunction(21, DeviceFunction.I2C1_DATA);
Configuration.SetPinFunction(22, DeviceFunction.I2C1_CLOCK);

For other devices like STM32, please make sure you're using the preset pins for the I2C bus you want to use. The sample reads two temperatures. One is a connected thermocouple reading which can be read using the GetTemperature command and the other is the temperature of the device itself which can be read using the GetColdJunctionTemperature command. The Cold Junction Temperature is used internally to increase the accuracy of the thermocouple.

using Iot.Device.Mcp960x;
using nanoFramework.Hardware.Esp32;
using System.Device.I2c;
using System.Diagnostics;
using System.Threading;

Debug.WriteLine("Write I2C MCP960X - ADR 0x67 - Read ambient and hot junction temperature every 1 sec");

// redefine I2C pins to match your ESP32 DevKit
// Configuration.SetPinFunction(21, DeviceFunction.I2C1_DATA);
// Configuration.SetPinFunction(22, DeviceFunction.I2C1_CLOCK);

// set I2C bus ID: 1
// 0x67 is the device address
I2cConnectionSettings settings = new I2cConnectionSettings(1, 0x67);
I2cDevice i2cDevice = I2cDevice.Create(settings);
Mcp960x mcp960x = new Mcp960x(i2cDevice, coldJunctionResolutionType: ColdJunctionResolutionType.N_0_25);

DeviceIDType deviceIDType;
byte major;
byte minor;
mcp960x.ReadDeviceID(out deviceIDType, out major, out minor);
Debug.WriteLine($"device id: {(byte)deviceIDType} - major: {major} - minor: {minor}");

while (true)
{
    Debug.WriteLine($"ambient temperture: {mcp960x.GetColdJunctionTemperature()}");
    Debug.WriteLine($"hot junction temperture: {mcp960x.GetTemperature()}");

    Thread.Sleep(1000);
}