STM32L031X4 Datasheet, PDF (54/118 Pages) STMicroelectronics – Access line ultra-low-power 32-bit MCU ARM-based Cortex-M0+, up to 32KB Flash, 8KB SRAM, 1KB EEPROM, ADC

Electrical characteristics
STM32L031x4/6
6.3.3
Embedded internal reference voltage
The parameters given in Table 23 are based on characterization results, unless otherwise
specified.
Table 22. Embedded internal reference voltage calibration values
Calibration value name
Description
Memory address
VREFINT_CAL
Raw data acquired at temperature
of 25 °C, V_DDA= 3 V
0x1FF8 0078 - 0x1FF8 0079
Table 23. Embedded internal reference voltage⁽¹⁾
Symbol
Parameter
Conditions
Min Typ
Max
Unit
V_{REFINT out(2)} Internal reference voltage
– 40 °C < T_J < +125 °C 1.202 1.224 1.242
V
T_VREFINT
Internal reference startup time
-
-
2
3
ms
V_{VREF_MEAS}
V_DDA voltage during V_REFINT
factory measure
-
2.99
3
3.01
V
A_{VREF_MEAS}
Accuracy of factory-measured
V_REFINT value⁽³⁾
Including uncertainties
due to ADC and V_DDA
values
-
T_Coeff(4)
A_Coeff(4)
V_DDCoeff(4)
Temperature coefficient
Long-term stability
Voltage coefficient
–40 °C < T_J < +125 °C
-
1000 hours, T= 25 °C
-
3.0 V < V_DDA < 3.6 V
-
ADC sampling time when
T_{S_vrefint(4)(5)} reading the internal reference
-
5
voltage
-
±5
mV
25
100 ppm/°C
-
1000 ppm
-
2000 ppm/V
10
-
µs
T_{ADC_BUF(4)}
Startup time of reference
voltage buffer for ADC
-
-
-
10
µs
I_{BUF_ADC(4)}
Consumption of reference
voltage buffer for ADC
-
-
13.5
25
µA
I_{VREF_OUT(4)} VREF_OUT output current⁽⁶⁾
-
-
-
1
µA
C_{VREF_OUT(4)} VREF_OUT output load
-
-
-
50
pF
Consumption of reference
I_LPBUF(4)
voltage buffer for VREF_OUT
-
-
730
1200
nA
and COMP
V_{REFINT_DIV1(4)}
V_{REFINT_DIV2(4)}
V_{REFINT_DIV3(4)}
1/4 reference voltage
1/2 reference voltage
3/4 reference voltage
-
24
25
26
-
49
50
51
%
V_REFINT
-
74
75
76
1. Refer to Table 35: Peripheral current consumption in Stop and Standby mode for the value of the internal reference current
consumption (I_REFINT).
2. Guaranteed by test in production.
3. The internal V_REF value is individually measured in production and stored in dedicated EEPROM bytes.
4. Guaranteed by design.
5. Shortest sampling time can be determined in the application by multiple iterations.
6. To guarantee less than 1% VREF_OUT deviation.
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