ak4420 AKM Semiconductor, Inc., ak4420 Datasheet - Page 9

• Manufacturer Part Number: ak4420
• Description: 192khz 24-bit Stereo ?? Dac With 2vrms Output
• Manufacturer: AKM Semiconductor, Inc.

■
The external clocks required to operate the AK4420 are MCLK, LRCK and BICK. The master clock (MCLK) should be
synchronized with LRCK but the phase is not critical. The MCLK is used to operate the digital interpolation filter and the
delta-sigma modulator. Sampling speed and MCLK frequency are detected automatically and then the internal master
clock is set to the appropriate frequency
The AK4420 is automatically placed in power saving mode when MCLK and LRCK stop during normal operation mode,
and the analog output is forced to 0V(typ). When MCLK and LRCK are input again, the AK4420 is powered up. After
power-up, the AK4420 is in the power-down mode until MCLK and LRCK are input.
When MCLK= 256fs/384fs, the AK4420 supports sampling rate of 32kHz~96kHz
is 32kHz~48kHz, DR and S/N will degrade by approximately 3dB as compared to when MCLK= 512fs/768fs.
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The audio data is shifted in via the SDTI pin using the BICK and LRCK inputs. The DIF pin can select between two serial
data modes as shown in
the rising edge of BICK. In one cycle of LRCK, eight “H” pulses or more must not be input to the DIF pin.
MS0683-E-04
System Clock
Audio Serial Interface Format
176.4kHz
192.0kHz
32.0kHz
44.1kHz
48.0kHz
32.0kHz
44.1kHz
48.0kHz
88.2kHz
96.0kHz
LRCK
fs
22.5792
24.5760
128fs
-
-
-
-
-
Table 2. Relationship between MCLK frequency and DR, S/N (fs= 44.1kHz)
Mode
Table
0
1
33.8688
36.8640
3. In all modes the serial data is MSB-first, two’s complement format and it is latched on
192fs
-
-
-
-
-
DIF
H
L
(Table
SDTI Format
24bit MSB justified
24bit I
256fs/384fs
512fs/768fs
11.2896
22.5792
24.5760
12.288
Table 1. System Clock Example
256fs
8.192
MCLK
OPERATION OVERVIEW
Table 3. Audio Data Formats
-
-
-
-
-
1).
2
S
MCLK (MHz)
16.9344
33.8688
36.8640
12.288
18.432
384fs
- 9 -
-
-
-
-
-
DR,S/N
16.3840
22.5792
24.5760
102dB
105dB
512fs
-
-
-
-
BICK
≥48fs
≥48fs
24.5760
33.8688
36.8640
(Table
768fs
-
-
-
-
Figure 3
Figure 4
Figure
2). But, when the sampling rate
36.8640
1152fs
-
-
-
-
-
-
Sampling
Normal
Double
Speed
Quad
[AK4420]
2008/06