MC68HC908QY4_10 Datasheet, PDF (161/168 Pages) Freescale Semiconductor, Inc – M68HC08 Microcontrollers

Analog-to-Digital Converter Characteristics
16.14 Analog-to-Digital Converter Characteristics
Characteristic
Symbol
Min
Max
Unit
Comments
Supply voltage
V_DDAD
2.7
(V_DD min)
5.5
(V_DD max)
V
—
Input voltages
V_ADIN
V_SS
V_DD
V
—
Resolution
(1 LSB)
RES
10.5
21.5
mV
—
Absolute accuracy
(Total unadjusted error)
E_TUE
—
± 1.5
LSB
Includes quantization
ADC internal clock
f_ADIC
0.5
1.048
MHz
t_ADIC = 1/f_ADIC,
tested only at 1 MHz
Conversion range
V_AIN
V_SS
V_DD
V
—
Power-up time
t_ADPU
16
—
t_ADIC cycles
t_ADIC = 1/f_ADIC
Conversion time
t_ADC
16
17
t_ADIC cycles
t_ADIC = 1/f_ADIC
Sample time⁽¹⁾
t_ADS
5
—
t_ADIC cycles
t_ADIC = 1/f_ADIC
Zero input reading⁽²⁾
Z_ADI
00
01
Hex
V_IN = V_SS
Full-scale reading⁽³⁾
F_ADI
FE
FF
Hex
V_IN = V_DD
Input capacitance
C_ADI
—
8
pF
Not tested
Input leakage⁽³⁾
I_IL
—
±1
μA
—
ADC supply current
V_DD = 3 V
V_DD = 5 V
I_ADAD
Typical = 0.45
mA
Typical = 0.65
mA
Enabled
Enabled
1. Source impedances greater than 10 kΩ adversely affect internal RC charging time during input sampling.
2. Zero-input/full-scale reading requires sufficient decoupling measures for accurate conversions.
3. The external system error caused by input leakage current is approximately equal to the product of R source and input
current.
MC68HC908QY/QT Family Data Sheet, Rev. 6
Freescale Semiconductor
161