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AK4649 Datasheet, PDF (12/96 Pages) Asahi Kasei Microsystems – 24bit Stereo CODEC with MIC/SPK-AMP
[AK4649]
FILTER CHARACTERISTICS
(Ta =25°C; AVDD=SVDD=2.4 ∼ 3.6V, DVDD =1.6 ∼ 3.6V; fs=44.1kHz; DEM=OFF)
Parameter
Symbol
min
typ
max
Units
ADC Digital Filter (Decimation LPF):
Passband (Note 23)
±0.16dB
PB
−0.66dB
0
-
17.3
kHz
-
19.4
-
kHz
−1.1dB
-
19.9
-
kHz
−6.9dB
-
22.1
-
kHz
Stopband
SB
26.1
-
-
kHz
Passband Ripple
PR
-
-
±0.1
dB
Stopband Attenuation
SA
73
-
-
dB
Group Delay (Note 24)
GD
-
19
-
1/fs
Group Delay Distortion
ΔGD
-
0
-
μs
ADC Digital Filter (HPF): HPFC1-0 bits = “00”
Frequency Response
−3.0dB
FR
-
3.4
-
Hz
−0.5dB
−0.1dB
-
10
-
Hz
-
22
-
Hz
DAC Digital Filter (LPF):
Passband (Note 23)
±0.05dB
PB
−6.0dB
0
-
20.0
kHz
-
22.05
-
kHz
Stopband
SB
24.1
-
-
kHz
Passband Ripple
PR
-
-
±0.02
dB
Stopband Attenuation
SA
54
-
-
dB
Group Delay (Note 24)
GD
-
20
-
1/fs
DAC Digital Filter (LPF) + SCF:
Frequency Response: 0 ∼ 20.0kHz
FR
-
±1.0
-
dB
Note 23. The passband and stopband frequencies scale with fs (system sampling rate).
For example, PB=20.0kHz (@−1.0dB) is 0.454 x fs (ADC). Each response refers to that of 1kHz
Note 24. The calculated delay time caused by digital filtering. This time is from the input of analog signal to setting of the
24-bit data of both channels from the input register to the output register of the ADC. This time includes the
group delay of the HPF. For the DAC, this time is from setting the 24-bit data of both channels from the input
register to the output of analog signal.
For the signal through the programmable filters (First HPF + First LPF + 4-band Equalizer + ALC + Equalizer),
group delay is increased 5/fs at Recording Mode or 7/fs at Playback Mode from the value above if there is no
phase change by the IIR filter.
MS1023-E-01
- 12 -
2010/08