ak4525 AKM Semiconductor, Inc., ak4525 Datasheet - Page 12

• Manufacturer Part Number: ak4525
• Description: 20bit Stereo ?? Adc & Dac With X? Tal Osc
• Manufacturer: AKM Semiconductor, Inc.

ASAHI KASEI
n De-emphasis Filter
The DAC of AK4525 includes the digital de-emphasis filter (tc=50/15µs) by IIR filter. This filter corresponds to three
frequencies (32kHz, 44.1kHz and 48kHz). The de-emphasis filter selected by DEM0 and DEM1 is enabled for input
audio data. The de-emphasis is also disabled at DEM0= “1” and DEM1= “0”.
n Soft Mute Operation
Soft mute operation is performed at digital domain. When SMUTE goes to “H”, the output signal is attenuated by -
during 1024 LRCK cycles. When SMUTE is returned to “L”, the mute is cancelled and the output attenuation gradually
changes to 0dB during 1024 LRCK cycles. If the soft mute is cancelled within 1024 LRCK cycles after starting the
operation, the attenuation is discontinued and returned to 0dB. The soft mute is effective for changing the signal source
without stopping the signal transmission.
Notes:
MS0053-E-00
(1) The output signal is attenuated by - during 1024 LRCK cycles (1024/fs).
(2) Analog output corresponding to digital input has the group delay (GD).
(3) If the soft mute is cancelled within 1024 LRCK cycles, the attenuation is discontinued and returned to 0dB.
SMUTE
Attenuation
0dB
-
Noise level
1024/fs
(1)
Table 3. De-emphasis filter control
DEM1
Figure 6. Soft Mute Operation
0
0
1
1
G D
DEM0
(2)
- 12 -
-100dB
0
1
0
1
44.1kHz
48kHz
32kHz
Mode
OFF
1024/fs
G D
(3)
[AK4525]
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