ASAHI KASEI
[AK4115]
Sampling Frequency and Pre-emphasis Detection
The AK4115 has two methods for detecting the sampling frequency:
1. Clock comparison between the recovered clock and X’tal oscillator
2. Sampling frequency information from channel status
The method is selected by the XTL1,0 pins. When XTL1, 0 = “1,1”, the sampling frequency is detected by the channel
status sampling frequency information. The detected frequency is available on the FS3-0 bits.
X’tal Frequency
XTL1
XTL0
X’tal #1
11.2896MHz
12.288MHz
X’tal #2
12.288MHz
11.2896MHz
0
0
1
1
0
1
0
1
Default
24.576MHz
(Use channel status)
22.5792MHz
(Use channel status)
Table 13. Reference X’tal frequency
Except XTL1, 0 = “1,1”
XTL1, 0 = “1, 1”
Consumer
mode
(Note 38)
Byte3
Bit3,2,1,0
Register output
Professional mode
(Note 39)
Clock comparison
fs
(Note 37)
Byte0
Byte4
FS3
FS2
FS1
FS0
Bit7,6
Bit6,5,4,3
0
0
0
0
0
0
1
1
1
1
1
0
0
0
0
1
1
0
0
0
1
1
44.1kHz
Reserved
48kHz
32kHz
22.05kHz
24kHz
64kHz
88.2kHz
96kHz
176.4kHz
192kHz
0 0 0 0
0 0 0 1
0 0 1 0
0 0 1 1
0 1 0 0
0 1 1 0
0 1
0
0
1
1
0
1
1
0
1
0
1
0
1
0
1
0
0
1
0
0
0
0
0 0 0 0
(Others)
44.1kHz ± 3%
-
48kHz ± 3%
1 0
1 1
0 0
0 0
0 0 0 0
0 0 0 0
1 0 0 1
0 0 0 1
32kHz 3%
±
22.05kHz 3%
±
24kHz ± 3%
64kHz ± 3%
88.2kHz ± 3%
96kHz ± 3%
1 0 0 0
1 0 1 0
1 1 0 0
1 1 1 0
0 0
0 0
0 0
0 0
1 0 1 0
0 0 1 0
1 0 1 1
0 0 1 1
176.4kHz 3%
±
192kHz ± 3%
Note 37: At least ±3% range is identified as the value in the Table 14. In case of intermediate frequency of those
two, FS3-0 bits indicate no value. When the frequency is ≥ 3% over 192kHz or ≤ 3% under 22kHz,
FS3-0 bits may indicate “0001”, “0101”, “0111” or “1001”.
Note 38: In consumer mode, Byte3 Bit3-0 are copied to FS3-0 bits.
Note 39. In professional mode, FS3-0 bit indicates “0001” except for frequency shown by Table 14.
Table 14. fs Information
MS0573-E-00
2006/12
- 26 -
AKM [ ASAHI KASEI MICROSYSTEMS ]
