CDCE421 Datasheet, PDF (3/30 Pages) Texas Instruments – Fully Integrated Wide-Range, Low-Jitter, Crystal-Oscillator Clock Generator

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DEVICE SETUP AND CONFIGURATION
CDCE421
SCAS842 – APRIL 2007
Table 1. Crystal Frequency Selection and Device Settings
DESIRED OUTPUT
FREQUENCY (MHz)
From
1020.0
875.2 ⁽²⁾
650.0
583.5
510.0
437.6
408.0
350.1
340.0
291.7
255.0
218.8
204.0
175.0
170.0
145.9
127.5
109.4
102.0
87.5
85.0
72.9
63.8
54.7
51.0
43.8
42.5
36.5
31.9
27.4
25.5
21.9
21.3
18.2
15.9
13.7
12.8
10.9
To
1175.0
1020.0
766.7 ⁽²⁾
650.0
587.5
510.0
460.0
408.0
383.3
340.0
293.8
255.0
230.0
204.0
191.7
170.0
146.9
127.5
115.0
102.0
95.8
85.0
73.4
63.8
57.5
51.0
47.9
42.5
36.7
31.9
28.8
25.5
24.0
21.3
18.4
15.9
14.4
12.8
REQUIRED INPUT
CRYSTAL
FREQUENCY (MHz)
From
To
31.875
36.719
27.351
31.875
32.500
38.333
29.174
32.500
31.875
36.719
27.351
31.875
34.000
38.333
29.174
34.000
34.000
38.333
29.174
34.000
31.875
36.719
27.351
31.875
34.000
38.333
29.174
34.000
34.000
38.333
29.174
34.000
31.875
36.719
27.351
31.875
34.000
38.333
29.174
34.000
34.000
38.333
29.174
34.000
31.875
36.719
27.351
31.875
34.000
38.333
29.174
34.000
34.000
38.333
29.174
34.000
31.875
36.719
27.351
31.875
34.000
38.333
29.174
34.000
34.000
38.333
29.174
34.000
31.875
36.719
27.351
31.875
34.000
38.333
29.174
34.000
VCO
SELECTION
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
VCO 2
VCO 1
OUTPUT
DIVIDER
1
1
1
1
1
1
1
1
2
2
2
2
2
2
4
4
4
4
4
4
8
8
8
8
8
8
16
16
16
16
16
16
32
32
32
32
32
32
PRESCALER
SETTING
2
2
3
3
4
4
5
5
3
3
4
4
5
5
3
3
4
4
5
5
3
3
4
4
5
5
3
3
4
4
5
5
3
3
4
4
5
5
(1) The feedback divider is set automatically with respect to the prescaler setting.
(2) Discontinuity in frequency range
FEEDBACK
DIVIDER ⁽¹⁾
32
32
20
20
16
16
12
12
20
20
16
16
12
12
20
20
16
16
12
12
20
20
16
16
12
12
20
20
16
16
12
12
20
20
16
16
12
12
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