ASAHI KASEI
[AK4528]
n Parallel/Serial Mode Control
When P/S= “H”, AK4528 is in parallel mode. The audio interface format is selected by DIF pin, and DFS and CK0-1 pins
select the frequency of MCLK.
When P/S= “L”, AK4528 is in serial mode. The CKS1, CKS0 and DIF pins are changed to CDTI, CCLK and CSN pins
respectively. The DEM0-1 and DFS are ORed between pin and register respectively, so those are able to control by pins
even in serial mode. To control all the functions by register, set DEM0-1 and DFS pins “L”.
n Digital High Pass Filter
The ADC has a digital high pass filter(HPF) for DC offset cancel. The cut-off frequency of the HPF is 0.9Hz at fs=44.1kHz
and also scales with sampling rate (fs). This HPF can be off for each channels by register.
n Output Volume
The AK4528 includes digital volumes (OATT) with 128 levels (including MUTE) in front of DAC. The OATT is a
pseudo-log volume linear-interpolated internally. When the level is changed, the transition to new value takes 8031
levels(max) and is done by soft transition. Therefore, there is not any switching noise.
n De-emphasis Filter
The DAC includes the digital de-emphasis filter (tc=50/15µs) by IIR filter. This filter supports to three frequencies
(32kHz, 44.1kHz and 48kHz). This setting is done by contorl register and always OFF at double speed mode.
No
0
1
2
3
DEM1
DEM0
Mode
44.1kHz
OFF
48kHz
32kHz
0
0
1
1
0
1
0
1
Default in serial mode
Table 6. De-emphasis control (DFS=”0”)
MS0011-E-00
2000/1
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AKM [ ASAHI KASEI MICROSYSTEMS ]
