Datasheet

STM32F051x Functional overview
Doc ID 022265 Rev 3 17/105
sensor, voltage reference, VBAT voltage measurement) channels and performs conversions
in single-shot or scan modes. In scan mode, automatic conversion is performed on a
selected group of analog inputs.
The ADC can be served by the DMA controller.
An analog watchdog feature allows very precise monitoring of the converted voltage of one,
some or all selected channels. An interrupt is generated when the converted voltage is
outside the programmed thresholds.
3.10.1 Temperature sensor
The temperature sensor (TS) generates a voltage V
SENSE
that varies linearly with
temperature.
The temperature sensor is internally connected to the ADC_IN16 input channel which is
used to convert the sensor output voltage into a digital value.
The sensor provides good linearity but it has to be calibrated to obtain good overall accuracy
of the temperature measurement. As the offset of the temperature sensor varies from chip
to chip due to process variation, the uncalibrated internal temperature sensor is suitable for
applications that detect temperature changes only.
To improve the accuracy of the temperature sensor measurement, each device is
individually factory-calibrated by ST. The temperature sensor factory calibration data are
stored by ST in the system memory area, accessible in read-only mode.
3.10.2 Internal voltage reference (V
REFINT
)
The internal voltage reference (V
REFINT
) provides a stable (bandgap) voltage output for the
ADC and Comparators. V
REFINT
is internally connected to the ADC_IN17 input channel. The
precise voltage of V
REFINT
is individually measured for each part by ST during production
test and stored in the system memory area. It is accessible in read-only mode.
Table 3. Temperature sensor calibration values
Calibration value name Description Memory address
TS_CAL1
TS ADC raw data acquired at
temperature of 30 °C,
V
DDA
= 3.3 V
0x1FFF F7B8 - 0x1FFF F7B9
TS_CAL2
TS ADC raw data acquired at
temperature of 110 °C
V
DDA
= 3.3 V
0x1FFF F7C2 - 0x1FFF F7C3
Table 4. Temperature sensor calibration values
Calibration value name Description Memory address
VREFINT_CAL
Raw data acquired at
temperature of 30 °C
V
DDA
= 3.3 V
0x1FFF F7BA - 0x1FFF F7BB