ST72325R6-AUTO STMicroelectronics, ST72325R6-AUTO Datasheet - Page 225

• Manufacturer Part Number: ST72325R6-AUTO
• Description: 8-bit Mcu For Automotive With 16 To 60 Kbyte Flash, Adc, Css, 5 Timers, Spi, Sci, I2c Interface
• Manufacturer: STMicroelectronics

ST72325xxx-Auto
19.12.1
Figure 95. R
1. C
(dependent on soldering and PCB layout quality) plus
the pad capacitance (3pF). A high C
downgrade conversion accuracy. To remedy this, f
should be reduced.
PARASITIC
45
40
35
30
25
20
15
10
5
0
0
Figure 97. Typical A/D converter application
Analog power supply and reference pins
Depending on the MCU pin count, the package may feature separate V
analog power supply pins. These pins supply power to the A/D converter cell and function
as the high and low reference voltages for the conversion.
Separation of the digital and analog power pins allow board designers to improve A/D
performance. Conversion accuracy can be impacted by voltage drops and noise in the event
of heavily loaded or badly decoupled power supply lines (see
design
represents the capacitance of the PCB
C
AIN
AIN
V
AIN
maximum versus f
= 0pF
guidelines).
10
C
PARASITIC
(1)
R
AIN
(pF)
30
PARASITIC
C
AIN
AINx
ADC
2 MHz
1 MHz
value will
70
with
ADC
Figure 96. Recommended C
1. This graph shows that, depending on the input signal
V
variation (f
time and decreased to allow the use of a larger serial
resistor (R
DD
V
0.6V
V
0.6V
1000
T
T
100
0.1
10
1
AIN)
AIN
values
0.01
), C
.
AIN
2kΩ(max)
I
lkg
(1)
can be increased for stabilization
Section 19.12.2: General PCB
0.1
Electrical characteristics
f
AIN
10-bit A/D
conversion
(KHz)
AREF
AIN
1
and R
Cain 10 nF
Cain 22 nF
Cain 47 nF
and V
ST72XXX
AIN
10
SSA
C
12pF
225/227
ADC