ST7FLITE29 STMICROELECTRONICS [STMicroelectronics], ST7FLITE29 Datasheet - Page 117

• Manufacturer Part Number: ST7FLITE29
• Description: 8-BIT MCU WITH SINGLE VOLTAGE FLASH MEMORY, DATA EEPROM, ADC, TIMERS, SPI
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

ADC CHARACTERISTICS (Cont’d)
ADC Accuracy with V
Notes:
1) Data based on characterization results over the whole temperature range, monitored in production.
2) Injecting negative current on any of the analog input pins significantly reduces the accuracy of any conversion being
performed on any analog input.
current on digital input pins degrades ADC accuracy especially if performed on a pin close to the analog input pins.
Any positive injection current within the limits specified for I
accuracy.
Figure 93. ADC Accuracy Characteristics with amplifier disabled
Symbol
Analog pins can be protected against negative injection by adding a Schottky diode (pin to ground). Injecting negative
1023
1022
1021
E
E
E
E
E
7
6
5
4
3
2
1
0
O
G
D
T
L
V
SS
Digital Result ADCDR
1LSB
1
Total unadjusted error
Offset error
Gain Error
Differential linearity error
Integral linearity error
E
O
2
I DE AL
3
2)
=
2)
V
------------------------------- -
4
DD
Parameter
DD
1024
=5.0V
–
5
1 LSB
V
SS
2)
2)
E
6
T
IDEAL
2)
E
7
L
(2)
E
D
1021 1022 1023 1024
(3)
f
CPU
INJ(PIN)
(1)
=8MHz, f
E
Conditions
G
and I
V
DD
ADC
(1) Example of an actual transfer curve
(2) The ideal transfer curve
(3) End point correlation line
E
between the actual and the ideal transfer curves.
E
transition and the first ideal one.
E
transition and the last actual one.
E
between actual steps and the ideal one.
E
between any actual transition and the end point
correlation line.
=4MHz
INJ(PIN)
T
O
G
D
L
=Total Unadjusted Error: maximum deviation
=Integral Linearity Error: maximum deviation
=Differential Linearity Error: maximum deviation
=Offset Error: deviation between the first actual
=Gain Error: deviation between the last ideal
V
in
(LSB
1)
in
Section 13.8
IDEAL
Typ
TBD
TBD
TBD
TBD
TBD
)
does not affect the ADC
Max
4.5
3.5
2
3
4
ST7LITE2
117/131
Unit
LSB