SENSE
SENSOR
SENSOR
V
TC
Temp
V
=
´
+
Device Descriptor Table
292
SLAU356I – March 2015 – Revised June 2019
Copyright © 2015–2019, Texas Instruments Incorporated
System Controller (SYSCTL)
4.9.3.2
Temperature Sensor Calibration
The temperature sensor calibration data is available as part of the ADC calibration descriptor (see
Table 4-6. ADC Calibration Data
ADC Calibration
Tag
00000005h
Length
00000018h
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
Reserved
Word
CAL_ADC_12T30
Word
CAL_ADC_12T85
Word
CAL_ADC_145T30
Word
CAL_ADC_145T85
Word
CAL_ADC_25T30
Word
CAL_ADC_25T85
The temperature sensor is calibrated using the internal voltage references. Each reference voltage (1.2 V,
1.45, V, or 2.5 V) contains a measured value for two temperatures, 30°C ±3°C and 85°C ±3°C, stored in
the TLV structure. The characteristic equation of the temperature sensor voltage, in millivolts is:
where
•
TC
SENSOR
, in mV/°C, is the temperature coefficient and represents the slope of the equation.
•
V
SENSOR
, in mV, represents the y-intercept of the equation.
•
Temp, in °C, is the temperature of interest.
(1)
The temperature (Temp, °C) can be computed as follows for each of the reference voltages used in the
ADC measurement: