STA333BW datasheet(17/68 Pages) STMICROELECTRONICS

17 / 68 page

DocID13773 Rev 5

17/68

STA333BW

Processing data paths

Figure 7 and Figure 8 below show the data processing paths inside STA333BW. The whole

processing chain is composed of 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 DRC block (2.0

output configuration with crossover filters used to define the cut-off frequency of the two

bands).

The first section, Figure 7, begins with a 2x oversampling FIR filter providing 2 * fS audio

processing. Then a selectable high-pass filter removes the DC level (enabled if HPB = 0).

The left and right channel processing paths can include up to 8 filters, depending on the

selected configuration (bits BQL, BQ5, BQ6, BQ7 and XO[3:0]). By default, four user

programmable, independent filters per channel are enabled, plus the preconfigured

de-emphasis, bass and treble controls (BQL = 0, BQ5 = 0, BQ6 = 0, BQ7 = 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.

Figure 7. Left and right processing, section 1

Moreover, the common 8th filter can be available on both channels provided the predefined

crossover frequencies are not used, XO[3:0] = 0, and the DRC is not used.

In the second section, Figure 8, mixing and crossover filters are available. If DRC is not

enabled they are fully user-programmable and allow the generation of a third channel

(2.1 outputs). Alternatively, in mode DRC, these blocks are used to split the sub-band and

define the cut-off frequencies of the two bands. A prescaler and a final postscaler allow full

control over the signal dynamics before and after the filtering stages. A mixer function is also

available.

From

I2S input

interface

PreScale

Biquad

If HPB=0

User Defined Filters

If DSPB=0 and C1EQBP=0

FIR

over

Sampling

frequency=Fs

Sampling

frequency=2xFs

From

I2S input

interface

PreScale

Hi-Pass

Filter

Hi-Pass

Filter

Biquad

De-Emph.

If DEMP=0

FIR

over

sampling

Sampling

frequency=Fs

Sampling

frequency=2xFs

Bass

Treble

If C1TCB=0

BTC: Bass Boost/Cut

TTC: Treble Boost/Cut

PreScale

Hi-Pass

Filter

Biquad

If HPB=0

User Defined Filters

If DSPB=0 and C2EQBP=0

FIR

over

PreScale

Hi-Pass

Filter

Biquad

De-Emph.

If DEMP=0

FIR

over

sampling

Bass

Treble

If C2TCB=0

BTC: Bass Boost/Cut

TTC: Treble Boost/Cut

If BQ5=1

and BQL=1

Biquad

If BQ6=1

and BQL=1

Biquad

IF BQ7=1

and BQL=1

Biquad

If BQ5=1

and BQL=1

Biquad

If BQ6=1

and BQL=1

Biquad

IF BQ7=1

and BQL=1

Biquad

From

I2S input

interface

PreScale

Biquad

If HPB=0

User Defined Filters

If DSPB=0 and C1EQBP=0

FIR

over

Sampling

frequency=Fs

Sampling

frequency=2xFs

From

I2S input

interface

PreScale

Hi-Pass

Filter

Hi-Pass

Filter

Hi-Pass

Filter

Hi-Pass

Filter

Biquad

De-Emph.

If DEMP=0

FIR

over

sampling

Sampling

frequency=Fs

Sampling

frequency=2xFs

Bass

Treble

If C1TCB=0

BTC: Bass Boost/Cut

TTC: Treble Boost/Cut

PreScale

Hi-Pass

Filter

Biquad

If HPB=0

User Defined Filters

If DSPB=0 and C2EQBP=0

FIR

over

PreScale

Hi-Pass

Filter

Biquad

De-Emph.

If DEMP=0

FIR

over

sampling

Bass

Treble

If C2TCB=0

BTC: Bass Boost/Cut

TTC: Treble Boost/Cut

If BQ5=1

and BQL=1

Biquad

If BQ6=1

and BQL=1

Biquad

IF BQ7=1

and BQL=1

Biquad

If BQ5=1

and BQL=1

Biquad

If BQ6=1

and BQL=1

Biquad

IF BQ7=1

and BQL=1

Biquad

STA333BW bảng dữ liệu(PDF) 17 Page - STMicroelectronics

STA333BW bảng dữ liệu(HTML) 17 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68

bảng dữ liệu tải về

Link URL