[AK4372]
Mode
0
1
2
FS3
0
0
FS2
0
0
0
FS1
0
0
FS0
0
1
fs
MCKI
256fs
512fs
1024fs
256fs
512fs
1024fs
256fs
512fs
1024fs
384fs
768fs
N/A
8kHz ∼ 48kHz
8kHz ∼ 48kHz
8kHz ∼ 24kHz
8kHz ∼ 48kHz
8kHz ∼ 48kHz
8kHz ∼ 24kHz
8kHz ∼ 48kHz
8kHz ∼ 48kHz
8kHz ∼ 24kHz
8kHz ∼ 48kHz
8kHz ∼ 24kHz
N/A
0
1
0
4
5
6
0
0
0
1
1
1
0
0
1
0
1
0
8
9
1
1
1
0
0
0
0
0
1
0
1
0
(default)
10
12
13
Others
1
1
1
1
0
0
0
1
Others
Table 11. Relationship between Sampling Frequency and MCKI Frequency (EXT mode) (N/A: Not available)
PS1
0
0
PS0
0
1
MCKO
256fs
128fs
64fs
(default)
1
0
1
1
32fs
Table 12. MCKO frequency (EXT mode, MCKO bit = “1”)
Master Mode (M/S bit = “1”)
Power Up (PMDAC bit = “1”)
Refer to Table 11
Power Down (PMDAC bit = “0”)
Input or
fixed to “L” or “H” externally
MCKI
pin
MCKO
pin
BICK
pin
LRCK
pin
MCKO bit = “0”: L
L
L
L
MCKO bit = “1”: Output
BF bit = “1”: 64fs output
BF bit = “0”: 32fs output
Output
Table 13. Clock Operation in Master mode (EXT mode)
Slave Mode (M/S bit = “0”)
Power Up (PMDAC bit = “1”) Power Down (PMDAC bit = “0”)
Input or
fixed to “L” or “H” externally
MCKI pin Refer to Table 11
MCKO bit = “0”: L
MCKO pin
L
MCKO bit = “1”: Output
BICK pin
LRCK pin
Input
Input
Fixed to “L” or “H” externally
Fixed to “L” or “H” externally
Table 14. Clock Operation in Slave mode (EXT mode)
For low sampling rates, DR and S/N degrade because of the out-of-band noise. DR and S/N are improved by using higher
frequency for MCKI. Table 15 shows DR and S/N when the DAC output is to the HP-amp.
DR, S/N (BW=20kHz, A-weight)
MCKI
fs=8kHz
56dB
75dB
fs=16kHz
75dB
90dB
256fs/384fs/512fs
768fs/1024fs
Table 15. Relationship between MCKI frequency and DR (and S/N) of HP-amp (2.4V)
MS0684-E-02
2008/12
- 23 -
AKM [ ASAHI KASEI MICROSYSTEMS ]
