ST72321B STMICROELECTRONICS [STMicroelectronics], ST72321B Datasheet - Page 167

• Manufacturer Part Number: ST72321B
• Description: 64/44-pin 8-bit MCU with 32 to 60K Flash/ROM, ADC, five timers, SPI, SCI, I2C interface
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

ADC CHARACTERISTICS (Cont’d)
Figure 93. R
Figure 95. Typical A/D Converter Application
Notes:
1. C
pacitance (3pF). A high C
2. This graph shows that depending on the input signal variation (f
decreased to allow the use of a larger serial resistor (R
PARASITIC
45
40
35
30
25
20
15
10
5
0
V
0
AIN
represents the capacitance of the PCB (dependent on soldering and PCB layout quality) plus the pad ca-
AIN
max. vs f
R
10
C
AIN
PARASITIC
PARASITIC
ADC
(pF)
C
30
AIN
with C
value will downgrade conversion accuracy. To remedy this, f
AINx
2 MHz
1 MHz
AIN
70
=0pF
1)
AIN)
.
V
DD
Figure 94. Recommended C
V
0.6V
V
0.6V
T
T
1000
AIN
100
0.1
10
1
), C
AIN
0.01
2kΩ(max)
can be increased for stabilization time and
I
±1µA
L
0.1
f
AIN
(KHz)
10-Bit A/D
Conversion
1
ADC
AIN
Cain 10 nF
Cain 22 nF
Cain 47 nF
should be reduced.
& R
10
AIN values.
ST72XXX
C
12pF
167/187
ADC
2)