STM32F100x4, STM32F100x6, STM32F100x8, STM32F100xB
Electrical characteristics
The above formula (Equation 1) is used to determine the maximum external impedance allowed for an
error below 1/4 of LSB. Here N = 12 (from 12-bit resolution).
(1)
Table 42.
R
max for f
= 12 MHz
AIN
ADC
Ts (cycles)
tS (µs)
RAIN max (k)
1.5
0.125
0.625
1.125
2.375
3.45
0.4
7.5
5.9
13.5
28.5
41.5
55.5
71.5
239.5
11.4
25.2
37.2
50
4.625
5.96
NA
20
NA
1. Guaranteed by design, not tested in production.
(1)(2)
Table 43. ADC accuracy - limited test conditions
Symbol
Parameter
Test conditions
Typ
Max
Unit
ET
EO
EG
ED
EL
Total unadjusted error
Offset error
1.3
1
2
fPCLK2 = 24 MHz,
fADC = 12 MHz, RAIN < 10 k,
VDDA = 3 V to 3.6 V
TA = 25 °C
1.5
1.5
1
Gain error
0.5
0.7
0.8
LSB
Differential linearity error
Integral linearity error
Measurements made after
ADC calibration
1.5
1. ADC DC accuracy values are measured after internal calibration.
2. Based on characterization, not tested in production.
(1) (2)
Table 44. ADC accuracy
Symbol
Parameter
Test conditions
Typ
Max(3)
Unit
ET
EO
EG
ED
EL
Total unadjusted error
Offset error
2
5
2.5
3
f
PCLK2 = 24 MHz,
1.5
1.5
1
fADC = 12 MHz, RAIN < 10 k,
VDDA = 2.4 V to 3.6 V
Gain error
LSB
Measurements made after
ADC calibration
Differential linearity error
Integral linearity error
2
1.5
3
1. ADC DC accuracy values are measured after internal calibration.
2. Better performance could be achieved in restricted VDD, frequency, VREF and temperature ranges.
3. Based on characterization, not tested in production.
Note:
ADC accuracy vs. negative injection current: Injecting a 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
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STMICROELECTRONICS [ ST ]
