STM32L081CB datasheet(26/110 Pages) STMICROELECTRONICS

26 / 110 page

Functional overview

STM32L081xx

26/110

DocID027513 Rev 4

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.

3.12.1

Internal voltage reference (VREFINT)

The internal voltage reference (VREFINT) provides a stable (bandgap) voltage output for the

ADC and Comparators. VREFINT is internally connected to the ADC_IN17 input channel. It

enables accurate monitoring of the VDD value . The precise voltage of VREFINT 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.

3.13

Ultra-low-power comparators and reference voltage

The STM32L081xx embed two comparators sharing the same current bias and reference

voltage. The reference voltage can be internal or external (coming from an I/O).



One comparator with ultra low consumption



One comparator with rail-to-rail inputs, fast or slow mode.



The threshold can be one of the following:

–

External I/O pins

–

Internal reference voltage (VREFINT)

–

submultiple of Internal reference voltage(1/4, 1/2, 3/4) for the rail to rail

comparator.

Both comparators can wake up the devices from Stop mode, and be combined into a

window comparator.

The internal reference voltage is available externally via a low-power / low-current output

buffer (driving current capability of 1 µA typical).

Table 6. Temperature sensor calibration values

Calibration value name

Description

Memory address

TSENSE_CAL1

TS ADC raw data acquired at

temperature of 30 °C,



VDDA= 3 V

0x1FF8 007A - 0x1FF8 007B

TSENSE_CAL2

TS ADC raw data acquired at

temperature of 130 °C



VDDA= 3 V

0x1FF8 007E - 0x1FF8 007F

Table 7. Internal voltage reference measured values

Calibration value name

Description

Memory address

VREFINT_CAL

Raw data acquired at

temperature of 25 °C

VDDA = 3 V

0x1FF8 0078 - 0x1FF8 0079

STM32L081CB Datasheet(PDF) 26 Page - STMicroelectronics

STM32L081CB Datasheet(HTML) 26 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL