AK7722 Datasheet, PDF (14/28 Pages) Asahi Kasei Microsystems – 24bit 4ch ADC + 24bit 4ch DAC with Audio DSP

[AK7722]
DIGITAL FILTER CHARACTERISTICS
■ ADC Block (ADC1/2)
1. fs=48kHz
(Ta=-40ºC ~85ºC, AVDD=DVDD=3.0~3.6V, fs=48kHz, Note 21)
Parameter
Symbol
min
typ
max
Unit
Passband (±0.1dB) (Note 22)
(-1.0dB)
(-3.0dB)
PB
0
18.9
kHz
20.0
kHz
23.0
kHz
Stopband
SB
28
kHz
Passband Ripple
(Note 22)
PR
±0.04
dB
Stopband Attenuation (Note 23, Note 24)
SA
68
dB
Group Delay Distortion
ΔGD
0
μs
Group Delay
(Ts=1/fs)
GD
16
Ts
Note 21. The passband and stopband frequencies are proportional to fs (system sampling rate). High-pass filter
characteristics are not included.
Note 22. The passband is from DC to 18.9kHz when fs=48kHz.
Note 23. The stopband is 28kHz to 3.044MHz when fs=48kHz.
Note 24. When fs = 48kHz, the analog modulator samples the input signal at 512kHz. There is no attenuation of an
input signal in band (n x 3.072MHz ±28kHz; n=0, 1, 2, 3…) of integer times of the sampling frequency by the
digital filter.
■ DAC1-2
(Ta=-40 ºC ~85 ºC; AVDD=DVDD=3.0~3.6V; fs=48kHz)
Parameter
Symbol
min
typ
max
Unit
Passband (±0.05dB) (Note 25)
PB
0
21.7
kHz
(-6.0dB)
24
kHz
Stopband
(Note 25)
SB
26.2
kHz
Passband Ripple
PR
±0.01
dB
Stopband Attenuation
SA
64
dB
Group Delay (Ts=1/fs) (Note 26)
GD
24
Ts
Digital Filter + Analog Filter
Amplitude Characteristics 20Hz~20.0kHz
±0.5
dB
Note 25. The pass band and stop band frequencies are proportional to “fs” (system sampling rate), and represents
PB=0.4535fs (@±0.05dB) and SB=0.5465fs, respectively.
Note 26. The digital filter delay is calculated as the time from setting data into the input register until an analog signal is
output.
MS1328-E-00-PB
14
2011/09