AK4438 Datasheet, PDF (23/63 Pages) Asahi Kasei Microsystems – 108dB 768kHz 32bit 8-Channel Audio DAC

[AK4438]
2. Auto Setting Mode (ACKS bit = “1”)
MCLK frequency and the sampling speed are detected automatically (Table 4) and DFS2-0 bits are
ignored. The MCLK frequency corresponding to each sampling speed should be provided externally
(Table 5, Table 6).
MCLK
Sampling Speed Mode
512fs/256fs 768fs/384fs Normal Speed Mode
256fs
384fs
Double Speed Mode
128fs
192fs
Quad Speed Mode
64fs
96fs
Oct Speed Mode
32fs
48fs
Hex Speed Mode
Table 4. Sampling Speed (Auto Setting Mode)
LRCK
fs
MCLK(MHz)
32fs 48fs 64fs
Sampling
96fs Speed
8.0kHz
N/A
N/A
N/A
N/A
44.1kHz N/A N/A
N/A
N/A Normal
48.0kHz N/A N/A
N/A
N/A
88.2kHz N/A N/A
96.0kHz N/A N/A
N/A
N/A
N/A
N/A
Double
176.4kHz N/A N/A
192.0kHz N/A N/A
N/A
N/A
N/A
N/A
Quad
384.0kHz N/A
N/A 24.576 36.864
Oct
768.0kHz 24.576 36.864 N/A
N/A
Hex
Table 5. System Clock Example (Auto Setting Mode)
LRCK
fs
8.0kHz
44.1kHz
48.0kHz
88.2kHz
96.0kHz
176.4kHz
192.0kHz
384.0kHz
768.0kHz
MCLK(MHz)
128fs 192fs 256fs 384fs 512fs 768fs
N/A
N/A 2.0480 3.0720 4.0960 6.1440
N/A
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
22.5792 33.8688 N/A
N/A
N/A
N/A
24.5760 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
Table 6. System Clock Example (Auto Setting Mode)
Sampling
Speed
Normal
Double
Quad
Oct
Hex
MCLK= 256fs/384fs supports sampling rate of 8kHz~96kHz (Table 7). 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 bit
MCLK
DR,S/N
L
256fs/384fs/512fs/768fs
108dB
H
256fs/384fs
105dB
H
512fs/768fs
108dB
Table 7. Relationship of DR, S/N and MCLK frequency (fs = 44.1kHz)
016001925-E-00
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2016/03