mc68hc908gr8b Freescale Semiconductor, Inc, mc68hc908gr8b Datasheet - Page 241

• Manufacturer Part Number: mc68hc908gr8b
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

19.12 ADC Characteristics
Freescale Semiconductor
Supply voltage
Input voltages
Resolution
Absolute accuracy
ADC internal clock
Conversion range
Power-up time
Conversion time
Sample time
Zero input reading
Full-scale reading
Input capacitance
Input leakage
1. V
2. Source impedances greater than 10 k adversely affect internal RC charging time during input sampling.
3. Zero-input/full-scale reading requires sufficient decoupling measures for accurate conversions.
4. The external system error caused by input leakage current is approximately equal to the product of R source and input
(V
Port B
current.
REFL
DD
= 5.0 Vdc 10%, V
= 0 V, V
(2)
(4)
Characteristic
DDAD
(3)
(3)
= V
REFH
SS
(1)
= 0 Vdc, V
= 5 V 10%)
DDAD
MC68HC908GR8B Data Sheet, Rev. 3.0
= 5.0 Vdc 10%, V
Symbol
V
V
t
f
C
ADPU
t
t
Z
B
A
R
F
DDAD
ADIC
ADC
ADIN
ADS
—
ADI
ADI
ADI
AD
AD
AD
V
(V
min)
Min
2.7
0.5
REFL
FE
16
16
00
—
—
0
8
5
SSAD
DD
= 0 Vdc, V
V
V
(20) 8
1.048
max)
(V
Max
DDAD
REFH
5.5
17
01
FF
—
8
DD
1
1
REFH
t
t
t
AIC
AIC
AIC
= 5.0 Vdc 10%, V
MHz
Unit
LSB
Hex
Hex
Bits
pF
cycles
cycles
cycles
V
V
V
A
V
the same potential as
Includes quantization
DDAD
t
AIC
ADC Characteristics
V
V
V
V
DD
only at 1 MHz
ADIN
REFH
V
REFL
V
Comments
= 1/f
REFL
Not tested
should be tied to
IN
IN
via separate
traces.
= V
= V
<= V
ADIC
= V
= V
= 0
REFH
REFL
DDAD
SSAD
, tested
REFH
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