Datasheet

Table Of Contents
Electrical Specifications
MC68HC908AB32Rev. 1.1 Technical Data
Freescale Semiconductor Electrical Specifications
383
23.12 Clock Generation Module Characteristics
23.12.1 CGM Operating Conditions
23.12.2 CGM Component Information
Characteristic Symbol Min Typ Max Comments
Operating Voltage
V
DD
4.5 V 5.5 V
Crystal Reference Frequency
f
RCLK
1—8.4
Module Crystal Reference
Frequency
f
XCLK
4.9152 MHz
Same Frequency as
f
RCLK
Range Nominal Multiplier
f
NOM
4.9152 MHz 4.5 to 5.5 V, V
DD
only
VCO Center-of-Range Frequency
(MHz)
f
VRS
4.9152 32.0 4.5 to 5.5 V, V
DD
only
VCO Operating Frequency (MHz)
f
VCLK
4.9152 32.0
Characteristic Symbol Min Typ Max Unit
Crystal load capacitance
C
L
———
Consult crystal
manufacturers data
Crystal fixed capacitance
C
1
2 × C
L
Consult crystal
manufacturers data
Crystal tuning capacitance
C
2
2 × C
L
Consult crystal
manufacturers data
Feedback bias resistor
R
B
—22M
Series resistor
R
S
330k 1M Not required
Filter capacitor multiply factor
C
Fact
0.0154 F/s V
Filter capacitor
C
F
C
Fact
× (V
DDA
/f
XCLK)
See 9.5.3 External Filter
Capacitor Pin
(CGMXFC).
Bypass capacitor
C
BYP
—0.1 µF—
C
BYP
must provide low
AC impedance from f =
f
XCLK
/100 to 100 ×
f
VCLK
, so series
resistance must be
considered.