Table 55. Rain Max For F Adc = 14 Mhz; Table 56. Adc Accuracy - STMicroelectronics STM32F042G4 Manual

STM32F042xx
The formula above
allowed for an error below 1/4 of LSB. Here N = 12 (from 12-bit resolution).
T (cycles)
s
1.5
7.5
13.5
28.5
41.5
55.5
71.5
239.5
1. Guaranteed by design, not tested in production.
Symbol
ET Total unadjusted error
EO Offset error
EG Gain error
ED Differential linearity error
EL Integral linearity error
ET Total unadjusted error
EO Offset error
EG Gain error
ED Differential linearity error
EL Integral linearity error
ET Total unadjusted error
EO Offset error
EG Gain error
ED Differential linearity error
EL Integral linearity error
1. ADC DC accuracy values are measured after internal calibration.
2. ADC Accuracy vs. Negative Injection Current: Injecting negative current on any of the standard (non-robust) analog input
pins should be avoided as this significantly reduces the accuracy of the conversion being performed on another analog
input. It is recommended to add a Schottky diode (pin to ground) to standard analog pins which may potentially inject
negative current.
Any positive injection current within the limits specified for I
accuracy.
3. Better performance may be achieved in restricted V
4. Data based on characterization results, not tested in production.
(Equation 1) is used to determine the maximum external impedance
Table 55. R

Table 56. ADC accuracy

Parameter
f
f
V
T
f
f
V
T
f
f
V
T
max for f = 14 MHz
AIN ADC
t (μs)
S
0.11
0.54
0.96
2.04
2.96
3.96
5.11
17.1
(1)(2)(3)
Test conditions
= 48 MHz,
PCLK
= 14 MHz, R < 10 k
ADC AIN
= 3 V to 3.6 V
DDA
= 25 °C
A
= 48 MHz,
PCLK
= 14 MHz, R < 10 k
ADC AIN
= 2.7 V to 3.6 V
DDA

= 40 to 105 °C
A
= 48 MHz,
PCLK
= 14 MHz, R < 10 k
ADC AIN
= 2.4 V to 3.6 V
DDA
= 25 °C
A
and I
INJ(PIN) INJ(PIN)
, frequency and temperature ranges.
DDA
DocID025832 Rev 2
Electrical characteristics
R max (k)
AIN
0.4
5.9
11.4
25.2
37.2
50
NA
NA
Typ Max
±1.3
±1 ±1.5
±0.5 ±1.5
±0.7
±0.8 ±1.5
±3.3
±1.9 ±2.8
±2.8
±0.7 ±1.3
±1.2 ±1.7
±3.3
±1.9 ±2.8
±2.8
±0.7 ±1.3
±1.2 ±1.7
in Section 6.3.14 does not affect the ADC
(1)
(4)
Unit
±2
LSB
±1
±4
±3 LSB
±4
±3 LSB
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