AK4631 Datasheet, PDF (32/69 Pages) Asahi Kasei Microsystems – 16-Bit Mono CODEC with ALC & MIC/SPK-AMP

ASAHI KASEI
[AK4631]
FCK
0 1 23 4
BICK(32fs)
9 10 11 12 13 14 15 0 1 2 3 4
9 10 11 12 13 14 15 0 1
SDT O( o)
15 14 13 7 7 6 5 4 3 2 1 0
SD T I( i)
15 14 13
76 54 32 1 0
0 1 23 4
BICK(64fs)
14 15 16 17 18
31 0 1 2 3 4 14 15 16 17 18
SDT O( o)
15 14 13
21 0
31 0 1
SD T I( i)
15 14 13
2 10
Don’t Care
15:MSB, 0:LSB
Data
1/fs
Figure 28. Mode 3 Timing
Don’t Care
„ σΟδλϧHPF
ADC͸DCΦϑηοτΩϟϯηϧ༻ͷHPFΛ಺ଂ͍ͯ͠·͢ɻHPFͷΧοτΦϑप೾਺͸0.62Hz (@fs=8kHz)
ʹͳ͓ͬͯΓɺαϯϓϦϯάप೾਺(fs)ʹൺྫ͠·͢ɻ
„ ϚΠΫ༻ήΠϯΞϯϓ
AK4631͸ϚΠΫ༻ήΠϯΞϯϓΛ಺ଂ͍ͯ͠·͢ɻMGAIN1-0 bits ʹΑΓɺήΠϯΛઃఆ͢Δ͜ͱ͕Ͱ͖·
͢ɻೖྗΠϯϐʔμϯε͸typ. 30kΩͰ͢ɻ
„ ϚΠΫύϫʔ
MGAIN1 bit
0
0
1
1
MGAIN0 bit Input Gain
0
0dB
1
+20dB
0
+26dB
1
+32dB
Table 14. Input Gain
Default
MPI pin͔ΒϚΠΫ༻ͷిݯΛ͢څڙΔ͜ͱ͕Ͱ͖·͢ɻग़ྗిѹ͸(0.75 x AVDD)V (typ)ʹൺྫ͠ɺෛՙ఍
߅͸ɺmin. 2kΩͰ͢ɻMPI pinʹίϯσϯα͸઀ଓ͠ͳ͍ͰԼ͍͞ɻ(Figure 29ࢀর)
MIC Power
MPI pin
MS0317-J-01
≥ 2k Ω
MIC pin
Microphone
MIC-Amp
Figure 29. MIC Block Circuit
- 32 -
2004/11