MC68HC908GR8A_07 Datasheet, PDF (247/260 Pages) Freescale Semiconductor, Inc – Microcontrollers

Clock Generation Module Characteristics
19.15 Clock Generation Module Characteristics
19.15.1 CGM Component Specifications
Characteristic
Crystal reference frequency⁽¹⁾
Crystal load capacitance⁽²⁾
Crystal fixed capacitance⁽²⁾
Crystal tuning capacitance⁽²⁾
Feedback bias resistor
Series resistor
1. Fundamental mode crystals only
2. Consult crystal manufacturer’s data.
19.15.2 CGM Electrical Specifications
Symbol
Min
f_XCLK
1
C_L
—
C₁
—
C₂
—
R_B
0.5
R_S
—
Typ
4
20
2 × C_L
2 × C_L
1
0
Max
Unit
8
MHz
—
pF
—
pF
—
pF
10
MΩ
—
Ω
Description
Operating voltage
Operating temperature
Crystal reference frequency
Range nominal multiplier
VCO center-of-range frequency
VCO range linear range multiplier
VCO power-of-two range multiplier
VCO multiply factor
VCO prescale multiplier
Reference divider factor
VCO operating frequency
Bus operating frequency (5-V operation)
Bus frequency (3-V operation)
Manual acquisition time
Automatic lock time
PLL jitter⁽¹⁾
Symbol
Min
V_DD
2.7
T_A
–40
f_RCLK
1
f_NOM
—
f_VRS
4
L
1
2^E
1
N
1
2^P
1
R
1
f_VCLK
4
f_BUS
—
f_BUS
—
t_Lock
—
t_Lock
—
f_J
0
External clock input frequency PLL disabled
f_OSC
dc
External clock input frequency PLL enabled
f_OSC
1
1. Deviation of average bus frequency over 2 ms. N = VCO multiplier.
Typ
—
25
4
38.4
—
—
—
—
1
1
—
—
—
—
—
—
—
4
Max
5.5
125
8
—
40
255
4
4095
8
15
40
8.2
4.1
5
5
f_RCLK x
0.025% x
2^P N/4
32.8 M
8
Unit
V
o_C
MHz
kHz
MHz
MHz
MHz
MHz
ms
ms
Hz
Hz
MHz
MC68HC908GR8A • MC68HC908GR4A Data Sheet, Rev. 5
Freescale Semiconductor
247