STM32F103x8, STM32F103xB
Table 48.
Symbol
ET
EO
EG
ED
EL
Electrical characteristics
ADC accuracy
(1) (2) (3)
Parameter
Total unadjusted error
Offset error
Gain error
Differential linearity error
Integral linearity error
f
PCLK2
= 56 MHz,
f
ADC
= 14 MHz, R
AIN
< 10 k,
V
DDA
= 2.4 V to 3.6 V
Measurements made after
ADC calibration
Test conditions
Typ
±2
±1.5
±1.5
±1
±1.5
Max
(4)
±5
±2.5
±3
±2
±3
LSB
Unit
1. ADC DC accuracy values are measured after internal calibration.
2. Better performance could be achieved in restricted V
DD
, frequency and temperature ranges.
3. 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
INJ(PIN)
and
I
INJ(PIN)
in
does not
affect the ADC accuracy.
4. Based on characterization, not tested in production.
Figure 36. ADC accuracy characteristics
V
V
[1LSB
IDEAL
=
REF+
(or
DDA
depending on package)]
4096
4096
E
G
4095
4094
4093
(2)
E
T
7
6
5
4
3
2
1
0
1
V
SSA
2
3
4
1 LSB
IDEAL
E
O
E
L
E
D
(3)
(1)
E
T
=Total Unadjusted Error: maximum deviation
between the actual and the ideal transfer curves.
E
O
=Offset Error: deviation between the first actual
transition and the first ideal one.
E
G
=Gain Error: deviation between the last ideal
transition and the last actual one.
E
D
=Differential Linearity Error: maximum deviation
between actual steps and the ideal one.
E
L
=Integral Linearity Error: maximum deviation
between any actual transition and the end point
correlation line.
(1) Example of an actual transfer curve
(2) The ideal transfer curve
(3) End point correlation line
5
6
7
4093 4094 4095 4096
V
DDA
ai14395b
Doc ID 13587 Rev 12
73/96
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