AK4116 Datasheet, PDF (13/36 Pages) Asahi Kasei Microsystems – LOW POWER 48KHZ DIGITAL AUDIO RECEIVER

ASAHI KASEI
[AK4116]
„ Sampling Frequency and Pre-emphasis Detection
The AK4116 has two methods for detecting the sample frequency:
1) Clock comparison between recovered clock and the X’tal oscillator
FS3-0 bits indicate the detected RX input frequency referred to X’tal frequency. XTL1-0 bits select the reference
X’tal frequency (Table 3).
2) Sampling frequency information on channel status
When XTL1-0= “11”, FS3-0 bits indicate the decoded sampling frequency information from channel status.
XTL1
0
0
1
1
XTL0
0
1
0
1
X’tal Frequency
11.2896MHz
12.288MHz
24.576MHz
(Use channel status)
Default
Table 3. Reference X’tal frequency
Except XTL1-0= “11”
XTL1-0= “11”
Register output
fs
FS3 FS2 FS1 FS0
Clock comparison
(Note 1)
Consumer
mode
(Note 2)
Byte3
Bit3,2,1,0
Professional mode
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
Reserved
0001
(Others)
0
0
1
0
48kHz
48kHz ± 3%
0010
10
0000
0
0
1
1
32kHz
32kHz ± 3%
0011
11
0000
1
0
0
0
Reserved
Reserved
(1000)
00
1010
1
0
1
0
Reserved
Reserved
(1010)
00
0010
1
1
0
0
Reserved
Reserved
(1100)
00
1011
1
1
1
0
Reserved
Reserved
(1110)
00
0011
Note 1: At least ±3% range is identified as the value in the Table 4. In case of an intermediate frequency of these two,
FS3-0 bits indicate the nearer value. When the frequency is much larger than 48kHz or much smaller than
32kHz, FS3-0 bits indicate any values except 32kHz, 44.1kHz and 48kHz.
Note 2: In consumer mode, Byte3 Bit3-0 are copied to FS3-0.
Table 4. Sampling frequency information
The pre-emphasis information is detected and reported on the PEM bit. This information is extracted from channel 1 by
default (CS12=0). It can be switched to channel 2 by changing the CS12 bit in the control register.
PEM Pre-emphasis
0
OFF
1
ON
Consumer mode
Byte 0
Bits 3-5
≠ 0X100
0X100
Professional mode
Byte 0
Bits 2-4
≠110
110
Table 5. Pre-emphasis information
MS0156-E-02
- 13 -
2004/04