wm8351 Wolfson Microelectronics plc, wm8351 Datasheet - Page 90

• Manufacturer Part Number: wm8351
• Description: Wolfson Audioplus? Stereo Codec With Power Management
• Manufacturer: Wolfson Microelectronics plc

WM8351
13.10 DIGITAL AUDIO INTERFACE
w
The audio interface enables the WM8351 to exchange audio data with other system components. It
is separate from the control interface and has four dedicated pins:
The LRCLK and BCLK pins are outputs when the WM8351 operates as a master device and are
inputs when it is a slave device.
In order to allow the ADC and DAC to run at different sampling rates, separate ADCLRCLK and
ADCBCLK signals are both available through GPIO pins: GPIO5 (ADCLRCLK) and GPIO6 or GPIO8
(ADCBCLK). This feature also allows mixed Master/Slave operation between the ADC and DAC.
13.10.1 AUDIO DATA FORMATS
The audio interface supports six different audio data formats:
In all of these formats, the MSB (most significant bit) of each data sample is transferred first and the
LSB (least significant bit) last.
R112 (70h)
Audio
Interface
ADDRESS
•
•
•
•
•
•
•
•
•
•
ADCDAT: Output pin for data coming from the audio ADC
DACDAT: Input pin for audio data going to the audio DAC
LRCLK: Data Left/Right alignment clock (also known as “word clock”)
BCLK: Bit clock, for synchronisation
Left justified
Right justified
I
DSP mode A
DSP mode B
TDM Mode
2
S
11:10
BIT
8:9
15
13
12
AIF_BCLK_INV
AIF_TRI
AIF_LRCLK_IN
V
AIF_WL [1:0]
AIF_FMT [1:0]
LABEL
DEFAULT
(24 bits)
10
10
0
0
0
edge after LRCLK rising edge (mode A)
1 = MSB is available on 1
edge after LRCLK rising edge (mode B)
Data word length
11 = 32 bits
10 = 24 bits
01 = 20 bits
00 = 16 bits
Note: When using the Right-Justified
data format (AIF_FMT=00), the
maximum word length is 24 bits.
BCLK polarity
0 = normal
1 = inverted
Sets Output enables for LRCLK and
BCLK and ADCDAT to inactive state
0 = normal
1 = forces pins to Hi-Z
LRCLK clock polarity
0 = normal
1 = inverted
DSP Mode – mode A/B select
0 = MSB is available on 2
Data format
DESCRIPTION
PD, June 2009, Rev 4.1
nd
st
Production Data
BCLK rising
BCLK rising
90