ZHCSKD9 October 2019 ADS1235-Q1
PRODUCTION DATA.
The ADC has an internal temperature sensor. The temperature sensor is comprised of two internal diodes with one diode having 80 times the current density of the other. The difference in current density of the diodes yields a differential output voltage that is proportional to absolute temperature. The temperature sensor reading is converted by the ADC. See Figure 39 for register settings to select the temperature sensor for measurement.
Equation 2 shows how to convert the temperature sensor reading to degrees Celsius (˚C):
Measure the temperature sensor with PGA on, gain = 1 and ac-bridge excitation mode disabled. As a result of the low package-to-PCB thermal resistance, the internal temperature closely tracks the PCB temperature.