Specifications

ST72325xx
170/197
12.12 10-BIT ADC CHARACTERISTICS
Subject to general operating conditions for V
DD
, f
CPU
, and T
A
unless otherwise specified.
Notes:
1. Any added external serial resistor will downgrade the ADC accuracy (especially for resistance greater than 10kΩ). Data
based on characterization results, not tested in production.
Symbol Parameter Conditions Min Typ Max Unit
f
ADC
ADC clock frequency 0.4 2 MHz
V
AREF
Analog reference voltage 0.7*V
DD
≤ V
AREF
≤ V
DD
3.8 V
DD
V
V
AIN
Conversion voltage range
1)
V
SSA
V
AREF
I
lkg
Positive input leakage current for analog
input
-40°C ≤ T
A
≤ 85°C range ±250 nA
Other T
A
ranges ±1 μA
Negative input leakage current on ro-
bust analog pins
V
IN
<V
SS,
| I
IN
|< 400µA
on adjacent robust ana-
log pin
56μA
R
AIN
External input impedance see
Figure 94
and
Figure 95
kΩ
C
AIN
External capacitor on analog input pF
f
AIN
Variation freq. of analog input signal Hz
C
ADC
Internal sample and hold capacitor 12 pF
t
ADC
Conversion time (Sample+Hold)
f
CPU
=8MHz, SPEED=0 f
ADC
=2MHz
7.5 μs
t
ADC
- No of sample capacitor loading cycles
- No. of Hold conversion cycles
4
11
1/f
ADC