AK7755EN_16 Datasheet, PDF (59/109 Pages) Asahi Kasei Microsystems – DSP with Mono ADC Stereo CODEC + Mic/Lineout Amp

[AK7755]
■ Serial Data Interface
Serial audio data pins; the SDIN1, SDIN2, SDOUT1, SDOUT2 and SDOUT3 pins are interfaced with
an external system by LRCK and BICK. Control register settings are needed to use these interfaces
(Refer to ■ Block Diagram (Figure 1) and Control register setting).
The data format is 2's compliment MSB first. I/O format supports MSB justified, LSB justified, I²S
compatible and PCM format. (In I²S compatible/PCM mode, all audio data input and output pins are in
I²S compatible/PCM format, respectively.)
The input (SDIN1 and SDIN2) format is 24-bit MSB justified at default. 24-bit/20-bit/16-bit LSB
justified, I²S and PCM formats are also selectable by control register DIF[1:0] bits. The output
(SDOUT1, ADOUT2 and SDOUT3) format is 24-bit MSB justified at default. 24-bit/20-bit/16-bit LSB
justified, I²S and PCM formats are selectable by setting DOF[1:0] bits. The SDOUT1 also supports 8-bit
MSB justified μ-Law and 8-bit MSB justifid A-Law formats. The output data of the ADC (SDOUTAD
and SDOUTAD2) is fixed to 24-bit MSB justified.
mode
0
1
2
3
4
5
6
7
8
LRIF[1:0]
000h
000h
000h
000h
0h
0h
011h
102h
113h
DIFDIF2, DIFDA[1:0]
or
DOF2, 3, 4[1:0]
000h
011h
102h
113h
N/A
N/A
000h
000h
000h
DIF1[2:0]
or
DOF1[2:0]
0h
1h
2h
3h
4h
5h
0h
0h
0h
BITFS[1:0] Format
0h
0h/1h
0h/1h
0h/1h/2h
0h
0h
0h
0h/3h
0h/3h
MSB 24-bit 64fs
LSB 24-bit 64fs/48fs
LSB 20-bit 64fs/48fs
LSB 16-bit 64fs/48fs/32fs
MSB 8-bit μ-Law
MSB 8-bit A-Law
I²S Compatible
PCM Short Frame 64fs/256fs
PCM Long Frame 64fs/256fs
Serial Data Format Examples
1. MSB justified (mode 0)
LRCK
Left ch
BICK
SDIN1, 2
DIF Mode 0
SDOUT1, 2, 3
DOF Mode 0
31 30 29 28 27
M 22 21 20 19
10 9 8 7 6 5 4 3 2 1 0 31 30 29 28 27
21L
M 22 21 20 19
M 22 21 20 19
21L
M 22 21 20 19
Figure 33. MSB Justified BICK 64fs
Right ch
10 9 8 7 6 5 4 3 2 1 0
2 1 L ^{M: MSB, L: LSB}
2 1 L ^{M: MSB, L: LSB}
014006643-E-00
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2014/10