wm8903 Wolfson Microelectronics plc, wm8903 Datasheet - Page 41

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

Pre-Production
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Figure 30 DRC Compression Characteristic
The slope of R0 and R1 are determined by register fields DRC_R0_SLOPE_COMP and
DRC_R1_SLOPE_COMP respectively. A slope of 1 indicates constant gain in this region. A slope
less than 1 represents compression (i.e. a change in input amplitude produces only a smaller change
in output amplitude). A slope of 0 indicates that the target output amplitude is the same across a
range of input amplitudes; this is infinite compression.
The “knee” in Figure 30 is represented by T and Y, which are determined by register fields
DRC_THRESH_COMP and DRC_AMP_COMP respectively.
Parameter Y0, the output level for a 0dB input, is not specified directly, but can be calculated from
the other parameters, using the equation
The DRC Compression parameters are defined in Table 15.
PP, Rev 3.1, August 2009
WM8903
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