WM8750L Datasheet, PDF (37/56 Pages) Wolfson Microelectronics plc – STEREO CODEC FOR PORTABLE AUDIO APPLICATIONS

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WM8750L
AUDIO DATA FORMATS
In Left Justified mode, the MSB is available on the first rising edge of BCLK following a LRCLK
transition. The other bits up to the LSB are then transmitted in order. Depending on word length,
BCLK frequency and sample rate, there may be unused BCLK cycles before each LRCLK transition.
DACLRC/
ADCLRC
BCLK
1/fs
LEFT CHANNEL
RIGHT CHANNEL
DACDAT/
ADCDAT
12
MSB
3
n-2 n-1 n
LSB
Input Word Length (WL)
123
MSB
n-2 n-1 n
LSB
Note: Input word length is defined by the WL register.
Timing is shown with LRP = 1
Figure 14 Left Justified Audio Interface (assuming n-bit word length)
In Right Justified mode, the LSB is available on the last rising edge of BCLK before a LRCLK
transition. All other bits are transmitted before (MSB first). Depending on word length, BCLK
frequency and sample rate, there may be unused BCLK cycles after each LRCLK transition.
DACLRC/
ADCLRC
BCLK
1/fs
LEFT CHANNEL
RIGHT CHANNEL
DACDAT/
ADCDAT
12
MSB
3
n-2 n-1 n
LSB
Input Word Length (WL)
123
MSB
n-2 n-1 n
LSB
Note: Input word length is defined by the WL register.
Timing is shown with LRP = 1
Figure 15 Right Justified Audio Interface (assuming n-bit word length)
In I²S mode, the MSB is available on the second rising edge of BCLK following a LRCLK transition.
The other bits up to the LSB are then transmitted in order. Depending on word length, BCLK
frequency and sample rate, there may be unused BCLK cycles between the LSB of one sample and
the MSB of the next.
DACLRC/
ADCLRC
BCLK
DACDAT/
ADCDAT
1/fs
LEFT CHANNEL
RIGHT CHANNEL
1 BCLK
123
n-2 n-1 n
MSB
LSB
Input Word Length (WL)
1 BCLK
123
MSB
n-2 n-1 n
LSB
Note: Input word length is defined by the WL register.
Timing is shown with LRP = 1
Figure 16 I²S Justified Audio Interface (assuming n-bit word length)
In DSP mode, the left channel MSB is available on either the 1^st (mode B) or 2^nd (mode A) rising
edge of BCLK (selectable by LRP) following a rising edge of LRCLK. Right channel data immediately
PP Rev 1.77 May 2003
37