wm8903 Wolfson Microelectronics plc, wm8903 Datasheet - Page 84

• Manufacturer Part Number: wm8903
• Description: Ultra Low Power Codec For Portable Audio Applications
• Manufacturer: Wolfson Microelectronics plc

WM8903
w
Figure 50 TDM in DSP Mode A
Figure 51 TDM in DSP Mode B
COMPANDING
The WM8903 supports A-law and μ-law companding on both transmit (ADC) and receive (DAC)
sides as shown in Table 55. Companding converts 13 bits (μ-law) or 12 bits (A-law) to 8 bits using
non-linear quantization. This provides greater precision for low-amplitude signals than for
high-amplitude signals, resulting in a greater usable dynamic range than 8 bit linear quantization.
Table 55 Companding Control
ADCDAT /
R24 (18h)
Audio
Interface 0
DACDAT
REGISTER
ADDRESS
BCLK
LRC
SLOT0 L
1 BCLK
BIT
3
2
1
0
ADC_COMP
ADC_COMPMO
DE
DAC_COMP
DAC_COMPMO
DE
SLOT0 R
LABEL
SLOT1 L
DEFAULT
1/fs
0
0
0
0
SLOT1 R
ADC Companding Enable
0 = disabled
1 = enabled
ADC Companding Type
0 = μ-law
1 = A-law
DAC Companding Enable
0 = disabled
1 = enabled
DAC Companding Type
0 = μ-law
1 = A-law
PP, Rev 3.1, August 2009
DESCRIPTION
Pre-Production
84