Processing data paths
4 Processing data paths
STA559BW
Figure 6 below shows the data processing paths inside STA559BW. The whole processing
chain can be considered as two consecutive sections. In the first one, dual-channel processing is implemented and in the second section each channel is fed into the post mixing block, either to generate a third channel (typically used in 2.1 output configuration and with crossover filters enabled) or to have the channels processed by the dual-band
DRC block (2.0 output configuration with crossover filters used to define the cut-off frequency of the two bands).
The first section contains a 2x oversampling FIR filter providing 2 * f
S
audio processing and a selectable high-pass filter to remove the DC level (enabled if HPB = 0).
If the coefficient sets for the two channels are linked (BQL = 1) it is possible to use the de-emphasis, bass and treble filters in a user defined configuration (provided the relevant
BQx bits are set). In this case both channels use the same processing coefficients and can have up to seven filters each. If BQL = 0 the BQx bits are ignored and the fifth, sixth and seventh filters are configured as de-emphasis, bass and treble controls, respectively.
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STA559BW
Figure 6. Left and right processing
Processing data paths
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