AK4687 AKM [Asahi Kasei Microsystems], AK4687 Datasheet - Page 17

• Manufacturer Part Number: AK4687
• Description: Asynchronous Stereo CODEC with Capless Stereo Selector
• Manufacturer: AKM [Asahi Kasei Microsystems]

■
The ADC has a digital high pass filter for DC offset cancellation. The cut-off frequency of the HPF is 1.0Hz at fs=48kHz
and frequency response scales with sampling rate (fs).
■
Each PORT1/2 can select audio interface format independently. The DIF1 bit controls audio data format of the PORT1.
The DIF1-0 bits control the audio data format of the PORT2. In all modes the serial data is MSB-first, 2’s complement
format. The SDTO pin is clocked out on the falling edge of BICK1 and the SDTI pin is latched on the rising edge of
BICK2. SDTI input formats can be used for 16-24bit data by zeroing the unused LSBs.
MS1307-E-00
1. PORT1 (ADC) Setting
2. PORT2 (DAC) Setting
Digital High Pass Filter
Audio Serial Interface Format
The MSN pin and DIF1 bit select following four serial data formats
The DIF21-20 bits select following four serial data formats
Mode
0
1
2
3
Mode
0
1
2
3
DIF21
bit
0
0
1
1
MSN
pin
L
L
H
H
DIF20
bit
0
1
0
1
DIF1
bit
0
1
0
1
16bit, Right justified
24bit, Right justified
Table 17. Audio Interface Format (ADC)
Table 18. Audio Interface Format (DAC)
24bit, Left justified
Left Justified
Left Justified
24bit, I
24bit, I
24bit, I
24/16bit
SDTO
SDTI
24bit
2
2
2
S
S
S
- 17 -
L/R
H/L
L/H
H/L
L/H
(Table
LRCK1
H/L
H/L
H/L
L/H
L/R
LRCK2
18).
(Table
I/O
O
O
I
I
I/O
I
I
I
I
17).
≥ 48fs or
≥ 48fs
speed
32fs
64fs
64fs
≥ 32fs
≥ 48fs
≥ 48fs
≥ 48fs
speed
BICK1
BICK2
I/O
O
O
I
I
I/O
I
I
I
I
(default)
(default)
(default)
[AK4687]
2011/05