
[AK4671]
MS0666-E-00
2007/10
- 100 -
■
System Clock (PCM I/F)
A reference clock of PLLBT is selected among the input clocks to SYNCA, BICKA, SYNCB or BICKB pin. The
required clock to PCM I/F is generated by an internal PLLBT circuit. PLLBT circuit is powered up by PMPCM bit. Input
frequency is selected by PLLBT3-0 bits (
Table 76
). BCKO2 bit select the output clock frequency of BICKA or BICKB
pin (
Table 77
). AK4671 does not support master mode for both PCM I/F A and B nor slave mode for both PCM I/F A and
B. Whether PCM I/F A or B should be set as slave mode. When PMPCM bit is “0”, SYNCA, BICKA, SYNCB and
BICKB pins are Hi-Z.
Table 78
indicates the output data of SDTOA and SDTOB pins in case of PMPCM bit = “0” and
during lock time in
Table 76
, respectively.
Table 79
indicates the output clock at master mode during lock time in
Table
76
.
R, C at
VCOCBT pin
R
6.8k
10k
10k
10k
6.8k
10k
10k
10k
10k
10k
Mode
PLLBT3
PLLBT2
PLLBT1
PLLBT0
Reference Clock
Input Pin
Frequency
C
Lock Time
(max)
(default)
0
1
2
3
4
5
6
7
11
15
0
0
0
0
0
0
0
0
1
1
0
0
0
0
1
1
1
1
0
1
0
0
1
1
0
0
1
1
1
1
Table 76. PLLBT Reference Clock (N/A: Not available)
0
1
0
1
0
1
0
1
1
1
SYNCA
BICKA
BICKA
BICKA
SYNCB
BICKB
BICKB
BICKB
BICKA
BICKB
N/A
1fs2
16fs2
32fs2
64fs2
1fs2
16fs2
32fs2
64fs2
48fs2
48fs2
220n
4.7n
4.7n
4.7n
220n
4.7n
4.7n
4.7n
4.7n
4.7n
260ms
40ms
40ms
40ms
260ms
40ms
40ms
40ms
40ms
40ms
Others
Note 65. Mode 1 is available at only FMTA1 bit = “0”.
Note 66. Mode 5 is available at only FMTB1 bit = “0”.
BCKO2 bit
BICKA/BICKB
Output Frequency
16fs2
32fs2
0
1
(default)
Table 77. BICKA/B Output Frequency
Mode
PMPCM bit = “0”
After PMPCM bit = “0”
→
“1”
& Before SYNCA/SYNCB Input
L
H
H
Table 78. SDTOA, SDTOB pins Output Data
PMPCM bit = “1”
During Locktime
0000H
11010101b
11111111b
16bit Linear
8bit A-Law
8bit
μ
-Law
L
L
L
Format
Except for I
2
S
I
2
S
SYNCA, SYNCB
L
H
BICKA, BICKB
L
L
Table 79. Output Clock during Lock Time