ASAHI KASEI
[AK4644]
FILTER CHARACTERISTICS
(Ta=25°C; AVDD, DVDD=2.6 ∼ 3.6V; HVDD=2.6 ∼ 5.25V; fs=44.1kHz; DEM=OFF; FIL1=FIL3=EQ=OFF)
Parameter
Symbol
min
typ
max
Units
ADC Digital Filter (Decimation LPF):
Passband (Note 24)
PB
0
-
-
-
-
19.4
19.9
22.1
-
-
-
19
0
17.3
-
-
-
kHz
kHz
kHz
kHz
kHz
dB
dB
1/fs
µs
±0.16dB
−0.66dB
−1.1dB
−6.9dB
Stopband
Passband Ripple
Stopband Attenuation
Group Delay (Note 25)
Group Delay Distortion
SB
PR
SA
GD
∆GD
26.1
-
-
73
-
±0.1
-
-
-
-
ADC Digital Filter (HPF): (Note 26)
Frequency Response (Note 24)
FR
-
-
-
0.9
2.7
6.0
-
-
-
Hz
Hz
Hz
−3.0dB
−0.5dB
−0.1dB
DAC Digital Filter (LPF):
Passband (Note 24)
PB
0
-
-
19.6
-
-
-
±0.01
-
-
kHz
kHz
kHz
kHz
dB
±0.1dB
−0.7dB
−6.0dB
20.0
22.05
-
-
-
-
25.2
-
59
-
Stopband
SB
PR
SA
GD
Passband Ripple
Stopband Attenuation
Group Delay (Note 25)
dB
1/fs
25
DAC Digital Filter (LPF) + SCF:
Frequency Response: 0 ∼ 20.0kHz
DAC Digital Filter (HPF): (Note 26)
FR
FR
-
-
dB
±1.0
Frequency Response (Note 24)
-
-
-
0.9
2.7
6.0
-
-
-
Hz
Hz
Hz
−3.0dB
−0.5dB
−0.1dB
BOOST Filter: (Note 27)
Frequency Response
MIN
20Hz
100Hz
1kHz
20Hz
100Hz
1kHz
FR
FR
FR
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
dB
dB
dB
dB
dB
dB
dB
dB
dB
5.76
2.92
0.02
10.80
6.84
0.13
16.06
10.54
0.37
MID
MAX 20Hz
100Hz
1kHz
Note 24. The passband and stopband frequencies scale with fs (system sampling rate).
For example, DAC is PB=0.454*fs (@−0.7dB). Each response refers to that of 1kHz.
Note 25. The calculated delay time caused by digital filtering. This time is from the input of analog signal to setting of the
16-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 16-bit data of both channels from the input
register to the output of analog signal. Group delay of DAC part is 25/fs(typ) at PMADL=PMADR bits = “0”.
Note 26. When PMADL bit = “1” or PMADR bit = “1”, the HPF of ADC is enabled but the HPF of DAC is disabled.
When PMADL=PMADR bits = “0”, PMDAC bit = “1”, the HPF of DAC is enabled but the HPF of ADC is
disabled.
Note 27. These frequency responses scale with fs. If a high-level and low frequency signal is input, the analog output clips
to the full-scale.
MS0477-E-01
2006/10
- 11 -
AKM [ ASAHI KASEI MICROSYSTEMS ]
