CMX649 CML Microcircuits, CMX649 Datasheet - Page 40

• Manufacturer Part Number: CMX649
• Description: ADM Codec
• Manufacturer: CML Microcircuits

ADM Codec
When selecting divider settings to arrive at a desired bit rate from a given crystal frequency, note that
some power savings are realized by selecting a lower divider value in conjunction with a higher prescaler
value, thus minimizing the frequency of the prescaler output.
Freq MHz
Freq MHz
11.2896
Crystal
Crystal
2003 CML Microsystems Plc
12.096
12.288
16.128
16.384
4.032
4.096
8.064
8.192
4.032
4.096
8.064
8.192
12
16
4
8
4
8
Divider values
Divider values
Register bits
Register bits
clk ctrl[5:3]
clk ctrl[7:6]
clk ctrl[5:3]
clk ctrl[7:6]
00
00
00
00
00
00
01
01
01
01
01
01
01
01
01
01
01
01
01
[2:0]
[2:0]
Applicable Bit Rate (kbps) Settings with Bit Rate Prescaler = 2
125.000
126.000
128.000
125.000
126.000
128.000
62.500
63.000
64.000
31.250
31.500
32.000
62.500
63.000
64.000
88.200
93.750
94.500
96.000
000
000
Bit Rate (kbps) Settings with Bit Rate Prescaler = 1
1
1
Crystal vs Divider chart for CMX649
Crystal vs Divider chart for CMX649
31.250
31.500
32.000
62.500
63.000
64.000
15.625
15.750
16.000
31.250
31.500
32.000
44.100
46.875
47.250
48.000
62.500
63.000
64.000
001
001
2
2
27.778
28.000
28.444
55.556
56.000
56.889
27.778
28.000
28.444
39.200
41.667
42.000
42.667
55.556
56.000
56.889
2.25
2.25
010
010
40
23.810
24.000
24.381
47.619
48.000
48.762
23.810
24.000
24.381
33.600
35.714
36.000
36.571
47.619
48.000
48.762
2.625
2.625
011
011
20.833
21.000
21.333
41.667
42.000
42.667
20.833
21.000
21.333
29.400
31.250
31.500
32.000
41.667
42.000
42.667
100
100
3
3
20.000
20.160
20.480
40.000
40.320
40.960
20.000
20.160
20.480
28.224
30.000
30.240
30.720
40.000
40.320
40.960
3.125
3.125
101
101
18.519
18.667
18.963
37.037
37.333
37.926
18.519
18.667
18.963
26.133
27.778
28.000
28.444
37.037
37.333
37.926
3.375
3.375
110
110
17.857
18.000
18.286
35.714
36.000
36.571
17.857
18.000
18.286
25.200
26.786
27.000
27.429
35.714
36.000
36.571
CMX649
D/649/2
111
111
3.5
3.5