S9S08SC4E0MTG Datasheet, PDF (19/31 Pages) Freescale Semiconductor, Inc – MC9S08SC4 8-Bit Microcontroller Data Sheet

Chapter 3 Electrical Characteristics
3.10 ADC Characteristics
Table 3-10. ADC Operating Conditions
Characteristic
Supply voltage
Input Voltage
Input
Capacitance
Input
Resistance
Conditions
Absolute
—
—
—
Symb
V_DDA2
V_ADIN
C_ADIN
Min
2.7
V_REFL2
—
Typ¹
—
—
4.5
Max Unit
5.5
V
V_REFH2
V
5.5
pF
R_ADIN
—
3
5
kΩ
Comment
—
—
—
—
Analog Source
Resistance
10 bit mode
f_ADCK > 4MHz
f_ADCK < 4MHz
R_AS
—
—
External to MCU
5
kΩ
—
—
10
8 bit mode (all valid f_ADCK)
—
—
10
ADC
High Speed (ADLPC=0)
f_ADCK
0.4
—
8.0
MHz
—
Conversion
Clock
Low Power (ADLPC=1)
0.4
—
4.0
Frequency
1 _{Typical values assume VDDA = 5.0 V, Temp = 25°C, fADCK=1.0 MHz unless otherwise stated. Typical values are for}
reference only and are not tested in production.
2 _{VDDA/VREFH and VSSA/VREFL, are derived from VDD and VSS respectively.}
R_AS
V_AS
+
–
Z_AS
C_AS
SIMPLIFIED
INPUT PIN EQUIVALENT
CIRCUIT
+
V_ADIN
–
Pad
leakage
due to
input
protection
Z_ADIN
SIMPLIFIED
CHANNEL SELECT
CIRCUIT
R_ADIN
ADC SAR
ENGINE
INPUT PIN
INPUT PIN
INPUT PIN
R_ADIN
R_ADIN
R_ADIN
C_ADIN
Figure 3-8. ADC Input Impedance Equivalency Diagram
MC9S08SC4 MCU Series Data Sheet, Rev. 4
Freescale Semiconductor
19