Temperature Conversion of MAX31856 Precision Thermocouple to Digital Converter

To convert a 24-bit digital output value to a real temperature value, follow these steps:
  1. For positive values:
    • Shift the 24-bit digital output value to obtain the 19-bit value. 
    • Convert the 19-bit binary number to decimal.
    • Multiply the decimal value by the resolution (0.0078125) to obtain the temperature value.
  2. For negative values:
    • Two possible methods can be used:
      • Method 1:
        • Shift the 24-bit digital output value to obtain the 19-bit digital output.
        • Invert these digits (changing 1's to 0's and vice versa).
        • Add one to the LSB to get the decimal value.
        • Multiply the decimal number by the resolution to obtain the temperature value.
      • Method 2:
        • Shift the 24-bit digital output value to obtain the 19-bit digital output.
        • Convert the 19-bit binary output to decimal.
        • Subtract 219 from the decimal value.
        • Multiply the result by the resolution number to get the temperature value.
Tags: Digital Temperature Sensors Integrated/Special Purpose A/D Converters MAX31856