AK4458 Datasheet, PDF (28/84 Pages) Asahi Kasei Microsystems – 115dB 768kHz 32-bit 8ch Premium DAC

[AK4458]
2. Auto Setting Mode (ACKS bit = “1”)
MCLK frequency and the sampling speed are detected automatically (Table 5) and DFS2-0 bits are ignored.
The MCLK frequency corresponding to each sampling speed should be provided externally (Table 6, Table 7).
MCLK
Sampling Speed
1152fs
Normal (fs32kHz)
512fs/256fs 768fs/384fs
Normal
256fs
384fs
Double
128fs
192fs
Quad
64fs
96fs
Oct
32fs
48fs
Hex
Table 5. Sampling Speed (Auto Setting Mode)
LRCK
MCLK(MHz)
fs
32fs 48fs 64fs 96fs 128fs
32.0kHz
N/A N/A N/A N/A N/A
44.1kHz
N/A N/A N/A N/A N/A
48.0kHz
N/A N/A N/A N/A N/A
88.2kHz
N/A N/A N/A N/A N/A
96.0kHz
N/A N/A N/A N/A N/A
176.4kHz
N/A N/A N/A N/A 22.5792
192.0kHz
N/A N/A N/A N/A 24.5760
384kHz
N/A N/A 24.576 36.864 N/A
768kHz 24.576 36.864 N/A N/A N/A
Table 6. System Clock Example (Auto Setting Mode)
Sampling
Speed
Normal
Double
Quad
Quad
Oct
Hex
LRCK
fs
32.0kHz
44.1kHz
48.0kHz
88.2kHz
96.0kHz
176.4kHz
192.0kHz
384kHz
768kHz
MCLK(MHz)
192fs
256fs
384fs 512fs 768fs 1152fs
N/A
8.1920 12.2880 16.3840 24.5760 36.8640
N/A 11.2896 16.9344 22.5792 33.8688 N/A
N/A 12.2880 18.4320 24.5760 36.8640 N/A
N/A 22.5792 33.8688 N/A
N/A
N/A
N/A 24.5760 36.8640 N/A N/A
N/A
33.8688 N/A
N/A
N/A N/A
N/A
36.8640 N/A
N/A
N/A N/A
N/A
N/A
N/A
N/A
N/A N/A
N/A
N/A
N/A
N/A
N/A N/A
N/A
Table 7. System Clock Example (Auto Setting Mode)
Sampling
Speed
Normal
Double
Quad
Quad
Oct
Hex
MCLK= 256fs/384fs supports sampling rate of 8kHz~96kHz (Table 8). However, when the sampling rate is
8kHz~48kHz, DR and S/N will degrade by approximately 3dB as compared to when MCLK= 512fs/768fs.
ACKS pin
MCLK
DR,S/N
L
256fs/384fs/512fs/768fs
115dB
H
256fs/384fs
112dB
H
512fs/768fs
115dB
Table 8. Relationship of DR, S/N and MCLK frequency (fs = 44.1kHz)
014011794-E-01
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2015/08