AK4118A Datasheet, PDF (18/56 Pages) Asahi Kasei Microsystems – High Feature 192kHz 24bit Digital Audio I/F Transceiver

[AK4118A]
■ Sampling Frequency and Pre-emphasis Detection
The AK4118A has two methods for detecting the sampling frequency as follows.
1. Clock comparison between recovered clock and X’tal oscillator
2. Sampling frequency information on channel status
Those could be selected by XTL1/0 pins. And the detected frequency is reported on FS3-0 and PEM bits.
XTL1
L
L
H
H
XTL0
X’tal Frequency
L
11.2896MHz
H
12.288MHz
L
24.576MHz
H
(Use channel status)
Table 6. Reference X’tal frequency
(default)
XTL1-0 bit ≠ “11”
XTL1-0 bit = “11”
Register output
fs
FS3 FS2 FS1 FS0
Clock comparison
(Note 11)
Consumer
mode
(Note 12)
Byte3
Bit3,2,1,0
Professional mode
(Note 13)
Byte0
Bit7,6
Byte4
Bit6,5,4,3
0
0
0
0
44.1kHz
44.1kHz ± 3%
0000
01
0000
0
0
0
1 Reserved
-
0001
(Others)
0
0
1
0
48kHz
48kHz ± 3%
0010
10
0000
0
0
1
1
32kHz
32kHz ± 3%
0011
11
0000
0
1
0
0 22.05kHz
22.05kHz ± 3%
0100
00
1001
0
1
0
1 11.025kHz
11.025kHz ± 3%
0
1
1
0
24kHz
24kHz ± 3%
0110
00
0001
0
1
1
1
16kHz
16kHz ± 3%
1
0
0
0
88.2kHz
88.2kHz ± 3%
1000
00
1010
1
0
0
1
8kHz
8kHz ± 3%
1
0
1
0
96kHz
96kHz ± 3%
1010
00
0010
1
0
1
1
64kHz
64kHz ± 3%
1
1
0
0 176.4kHz
176.4kHz ± 3%
1100
00
1011
1
1
1
0
192kHz
192kHz ± 3%
1110
00
0011
Note 11. At least ±3% frequency range is identified as the values in the Table 7. FS3-0 bits indicate nearer frequency for
the intermediate frequency of two values. When the frequency is over the range of 32kHz to 192kHz, FS3-0
bits may indicate “0001”.
Note 12. When consumer mode, Byte3 Bit3-0 are copied to FS3-0.
Note 13. In professional mode, FS3-0 bits are always “0001” except for the frequencies listed in the table.
Table 7. Sampling Frequency Information
The pre-emphasis information is detected and reported on PEM bit. This information is extracted from channel 1 at
default. It can be switched to channel 2 by CS12 bit in control register.
PEM Pre-emphasis Byte 0, Bits 3-5
0
OFF
≠ 0X100
1
ON
0X100
Table 8. PEM in Consumer Mode
PEM Pre-emphasis Byte 0, Bits 2-4
0
OFF
≠110
1
ON
110
Table 9. PEM in Professional Mode
MS1130-E-02
- 18 -
2009/12