L64704 LSI Logic Corporation, L64704 Datasheet - Page 214

• Manufacturer Part Number: L64704
• Description: Satellite Decoder Technical Manual 5/97
• Manufacturer: LSI Logic Corporation

C.4
Higher
Frequency
Oscillators
Figure C.3
A Third Overtone
(Higher Frequency)
Oscillator Circuit
Table C.2
Component Values
for the Circuit
Shown in
Figure C.3
C-4
C
Frequency ranges between 20 MHz and 60 MHz can be obtained with
the circuit shown in
1. R
Values are chosen for the components in
following considerations:
where C
connection capacitance (typically 3 pF).
where f is the desired frequency specified on the crystal.
shows typical component values for a range of frequencies.
Frequency
25 MHz
32 MHz
40 MHz
50 MHz
Oscillator Cells
f
f
1
R
1 to 5 Meg ohms.
C
1
3
DC
=
DC
1
Crystal
C
= the DC resistance of the crystal. R
2 R
4
2
L
OSCXX
=
= Crystal Parameter (typically 22 to 25 pF) and C
L
2
2 C
2
C
47
47
47
47
C
2
C
2
(pF)
2
L
R
C
–
and
Figure
2
2
C
B
L
2
R
120
100
80
60
2
C.3.
( )
C
DC
> 500 pF
DC
L
1.9
1.2
0.8
0.5
2
( H)
should be in the range from
Figure C.3
based on the
Table C.2
B
= board