ak4683 AKM Semiconductor, Inc., ak4683 Datasheet - Page 32

• Manufacturer Part Number: ak4683
• Description: Asynchronous Multi-channel Audio Codec With Dir/t
• Manufacturer: AKM Semiconductor, Inc.

■
The AK4683 includes the digital de-emphasis filter (tc=50/15μs) by IIR filter. De-emphasis filter is not available in
Double Speed Mode and Quad Speed Mode. This filter corresponds to three sampling frequencies (32kHz, 44.1kHz,
48kHz). De-emphasis of each DAC can be set individually by register.
■
The ADC has a digital high pass filter for DC offset cancel. The cut-off frequency of the HPF is 1.0Hz at fs=48kHz and
scales with sampling rate (fs).
■
Each PORTA/B can select independent audio interface format. The TDMA1-0, DIFA1-0 bits control the audio format
for PORTA and support normal mode, TDM256 mode and TDM128 mode. The DIFB1-0 bits control the audio format
for PORTB and support only normal mode. The default is mode 2. In all modes the serial data is MSB-first, 2’s
complement format. The SDTO pins are clocked out on the falling edge of BICK pins and the SDTI pins are latched on
the rising edge of BICK pins.
MS0427-E-02
1. Setting for the PORTA
1-1. Normal mode: TDMA1-0 bit = “00”
De-emphasis Filter
Digital High Pass Filter
Audio Serial Interface Format
Mode
The TDMA1-0 bits = “00” set the AK4683 audio serial interface format to the normal mode. The DIFA1-0 bits
select following eight serial data format (Table 31).
0
1
2
3
4
5
6
7
Master
Master
Master
Master
Master
/slave
Slave
Slave
Slave
Slave
Table 31 Audio Interface Format (Normal mode, L J: Left justified, R J: Right justified.)
Mode
0
1
2
3
DIFA1
0
0
1
1
0
0
1
1
Sampling Speed
Normal Speed
Normal Speed
Normal Speed
Normal Speed
DIFA0
0
1
0
1
0
1
0
1
Table 30. De-emphasis control
24bit, L J
24bit, L J
24bit, L J
24bit, I
24bit, L J
24bit, L J
24bit, L J
24bit, I
SDTOA
DEM1
2
2
- 32 -
S
S
0
0
1
1
SDTIA1-3
20bit, R J
24bit, R J
20bit, R J
24bit, R J
24bit, L J
24bit, I
24bit, L J
24bit, I
DEM0
2
2
S
S
0
1
0
1
H/L
H/L
L/H
L/H
H/L
H/L
H/L
H/L
LRCKA
44.1kHz
48kHz
32kHz
DEM
OFF
I/O
O
O
O
O
I
I
I
I
≥ 48fs
≥ 48fs
≥ 48fs
≥ 48fs
64fs
64fs
64fs
64fs
BICKA
(default)
I/O
O
O
O
O
I
I
I
I
(default)
[AK4683]
2007/04