Datasheet

Table Of Contents
Functional overview STM32WLE5J8/JB/JC
38/135 DS13105 Rev 4
The events generated by the general-purpose timers (TIMx) can be internally connected to
the ADC start triggers, to allow the application to synchronize A/D conversions with timers.
3.16.1 Temperature sensor
The temperature sensor (TS) generates a V
TS
voltage that varies linearly with temperature.
The temperature sensor is internally connected to the ADC VIN[12] input channel, 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 may
vary from part to part due to process variation, the uncalibrated internal temperature sensor
is suitable only for relative temperature measurements.
To improve the accuracy of the temperature sensor, each part is individually factory-
calibrated by ST. The resulting calibration data is stored in the device engineering bytes,
accessible in read-only mode.
3.16.2 Internal voltage reference (V
REFINT
)
V
REFINT
provides a stable (bandgap) voltage output for the ADC and comparators. V
REFINT
is internally connected to the ADC VIN[13] input channel.
V
REFINT
is individually and precisely measured, for each part, by ST, during production test
and stored in the device engineering bytes. It is accessible in read-only mode.
3.16.3 V
BAT
battery voltage monitoring
This embedded hardware feature allows the application to measure the V
BAT
battery voltage
using the ADC VIN[14] input channel. As V
BAT
may be higher than V
DDA
, and thus outside
the ADC input range, the VBAT pin is internally connected to a bridge divider by three. As a
consequence, the converted digital value is one third the V
BAT
voltage.
Table 12. Temperature sensor calibration values
Calibration value
name
Description Memory address
TS-CAL1
TS ADC raw data acquired at 30 °C (± 5 °C),
V
DDA
= V
REF+
= 3.3 V (± 10 mV)
0x1FFF 75A8 - 0x1FFF 75A9
TS_CAL2
TS ADC raw data acquired at 130 °C (± 5 °C),
V
DDA
= V
REF+
= 3.3 V (± 10 mV)
0x1FFF 75C8 - 0x1FFF 75C9
Table 13. Internal voltage reference calibration values
Calibration value name Description Memory address
VREFINT
Raw data acquired at 30 °C (± 5 °C),
V
DDA
= V
REF+
= 3.0 V (± 10 mV)
0x1FFF 75AA - 0x1FFF 75AB