[ASAHI KASEI]
Audio Block Diagram
Figure 9 shows audio codec block diagram
MICOUT
AIN
AFILT
1/64 times 4th order
4th order
20dB fixed
AMP
-8dB to 27.5dB
AGC
MICIN
decimation digital filter
Σ ∆ modulator
fs
(64 times oversampling)
128fs/
256fs
8fs
CTF &
1bit SC DAC
& 2nd order
LOUT
ROUT
Out Buff
Digital Σ ∆ modulator
4th order,
8 times interpolation
digital filter(LPF type)
Digital ATT
fs
fs
0 to 22.5dB
16bit
2ch
128/256 time oversampling
CTF &
1bit SC DAC
& 2nd order
Out Buff
Figure 9. Audio Codec Block Diagram
<Revision 0.9a>
15
July 00