SLAU723A October 2017 – October 2018 MSP432E401Y , MSP432E411Y
The temperature sensor serves two primary purposes: 1) to notify the system that internal temperature is too high or low for reliable operation and 2) to provide temperature measurements for calibration of the Hibernate module RTC trim value.
The temperature sensor does not have a separate enable, because it also contains the bandgap reference and must always be enabled. The reference is supplied to other analog modules; not just the ADC. In addition, the temperature sensor has a second power-down input in the 3.3 V domain which provides control by the Hibernation module.
The internal temperature sensor converts a temperature measurement into a voltage. This voltage value, VTSENS, is given by the following equation (where TEMP is the temperature in °C):
This relation is shown in Figure 10-11.
The temperature sensor reading can be sampled in a sample sequence by setting the TSn bit in the ADCSSCTLn register. The sample and hold width should be configured for at least 16 ADC clocks using the ADCSSTSHn register. The temperature reading from the temperature sensor can also be given as a function of the ADC value. The following formula calculates temperature (TEMP in ℃) based on the ADC reading (ADCCODE, given as an unsigned decimal number from 0 to 4095) and the maximum ADC voltage range (VREFP – VREFN) :