AK4679EG Datasheet, PDF (121/220 Pages) Asahi Kasei Microsystems – 24bit Stereo CODEC with DSP and MIC/RCV/HP/SPK/LINE-AMP

[AK4679]
■ System Clock (PCM I/F)
The AK4679 has two PCM I/F ports. PCM I/F A is for baseband module and PCM I/F B is for Bluetooth mode. PCM I/F
A, PCM I/F B and Audio I/F can be operated by asynchronous clock because the AK4679 has four SRCs. PCM I/F A and
PCM I/F B support slave mode only. The required clock PCM I/F is BICKA (BICKB) and SYNCA (SYNCB).When
PMPCMA bit is “1”, PCM I/F A port is powered-up. When PMPCMB bit is “1”, PCM I/F B port is powered-up.
CODEC
SYNCA
BICKA
SDTOA
SDTIA
1fs2
≥ 16fs2
DSP
SYNC2
SYNC1
BCLK2
SDIN2
BCLK1
SDOUT1
SDOUT2
SDOUT2
Baseband
SYNC
BICK
SDTI
SDTO
SYNCB
BICKB
SDTOB
SDTIB
1fs3
16fs3 or ≥ 32fs3
Bluetooth Module
SYNC
BICK
SDTI
SDTO
Figure 87. PCM I/F A and B
■ SRC (Sample Rate Converter)
The AK4679 has four asynchronous SRCs. The SRCs are operated by internal oscillator. When PMSRAI, PMSRAO,
PMSRBI or PMSRBO bit is “1” and PMOSC bit is “1”, SRC starts operation. Initial time of SRC is 164/fs2(164/fs3) for
SDTOA(SDTOB) output enable after power-down state is released by a clock input(SYNC clock). Until then, SDTOA
and SDTOB output data as shown in Table 113. Ratio of Input / Output is decided by PMMIX bit.
Mode
PMSRx bit = “0”
After PMSRx bit = “0” → “1”
& Before SYNCA/SYNCB Input
PMSRx bit = “1”
During initial time
16bit Linear
L
L
0000H
8bit A-Law
L
H
11010101b
8bit μ-Law
L
H
11111111b
Table 113. SDTOA and SDTOB pins Output Data (PMSRx: PMSRAI, PMSRAO, PMSRBI, PMSRBO)
PMMIX
bit
0
1
SRC
Input Sampling Rate
(FSI)
Output Sampling Rate
(FSO)
SRCAI
SYNCA
SYNCB
SRCAO
SYNCB
SYNCA
SRCAI
SYNCA
LRCK
SRCAO
LRCK
SYNCA
SRCBI
SYNCB
LRCK
SRCBO
LRCK
SYNCB
Table 114. PCM I/F Input Output rate
MS1402-E-06
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2013/02