
ASAHI KASEI 
[AK4640] 
MS0273-E-00 
2004/03 
- 14 - 
FILTER CHARACTERISTICS 
(Ta=
10 
~
 70
°
C; AVDD, DVDD, PVDD, HVDD=2.4 
~
 3.6V; fs=44.1kHz; DEM=OFF) 
Parameter 
ADC Digital Filter (Decimation LPF):
Passband 
(Note 20) 
±
0.1dB 
1.0dB 
3.0dB 
Stopband 
Passband Ripple 
Stopband Attenuation 
Group Delay 
(Note 21) 
Group Delay Distortion 
ADC Digital Filter (HPF):
Frequency Response (Note 20) 
3.0dB 
0.5dB 
0.1dB 
DAC Digital Filter:
Passband 
(Note 20) 
±
0.1dB 
0.7dB 
6.0dB 
Stopband 
Passband Ripple 
Stopband Attenuation 
Group Delay 
(Note 21) 
DAC Digital Filter + SCF:
Frequency Response: 0 
~
 20.0kHz 
BOOST Filter:
(Note 22) 
MIN 
20Hz 
100Hz 
1kHz 
MID 
20Hz 
100Hz 
1kHz 
MAX 
20Hz 
100Hz 
1kHz 
Note 20. The passband and stopband frequencies scale with fs (system sampling rate). 
  For example, ADC is PB=0.454*fs (@-1.0dB), DAC is PB=0.454*fs (@-0.01dB). 
Note 21. The calculated delay time caused by digital filtering. This time is from the input of analog signal to setting of the 
16bit 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 16bit data of both channels from the input register to 
the output of analog signal. 
Note 22. These frequency responses scale with fs. If a high-level and low frequency signal is input, the analog output clips 
to the full-scale. 
Symbol 
min 
typ 
max 
Units 
PB 
SB 
PR 
SA 
GD 
GD 
0 
- 
- 
- 
17.4 
- 
- 
- 
±
0.1 
- 
- 
- 
kHz 
kHz 
kHz 
kHz 
dB 
dB 
1/fs 
μ
s 
20.0 
21.1 
- 
- 
- 
17.0 
0 
25.7 
- 
65 
- 
- 
FR 
- 
- 
- 
3.4 
10 
22 
- 
- 
- 
Hz 
Hz 
Hz 
PB 
SB 
PR 
SA 
GD 
0 
- 
- 
- 
19.6 
- 
- 
- 
±
0.01 
- 
- 
kHz 
kHz 
kHz 
kHz 
dB 
dB 
1/fs 
20.0 
22.05 
- 
- 
- 
16.8 
25.2 
- 
59 
- 
FR 
- 
±
1.0 
- 
dB 
FR 
FR 
FR 
- 
- 
- 
- 
- 
- 
- 
- 
- 
5.74 
2.92 
0.0 
5.94 
4.71 
0.14 
16.04 
10.55 
0.3 
- 
- 
- 
- 
- 
- 
- 
- 
- 
dB 
dB 
dB 
dB 
dB 
dB 
dB 
dB 
dB 
Frequency Response