TAS5504 datasheet(17/96 Pages) TI

17 / 96 page

Introduction

SLES123 − October 2004

TAS5504

1.3.5 Digital Audio Processor (DAP)

The DAP arithmetic unit is used to implement all audio processing functions – soft volume, loudness

compensation, bass and treble processing, dynamic range control, channel filtering, input and output mixing.

Figure 1−4 shows the TAS5504 DAP architecture.

The DAP accepts 24-bit data signal from the serial data interface and outputs 32-bit data to the PWM section.

The DAP supports two configurations, one for 32-kHz – 96-kHz data and one for 176.4-kHz to 192-kHz data.

1.3.5.1

TAS5504 Audio Processing Configurations

The 32 − 96 kHz configuration supports four channels of data processing.

The 176.4 − 192 kHz configuration supports three channels of signal processing with one channel passed

though (or derived from the three processed channels).

To efficiently support the processing requirements of both multi-channel 32 – 96-kHz data and the two channel

176.4 and 192-kHz data, the TAS5504 supports separate audio processing features for 32 –96-kHz data rates

and for 176.4 and 192 kHz. See Table 2 for a summary of TAS5504 processing feature sets.

1.3.5.2

TAS5504 Audio Signal Processing Functions

The DAP provides 10 primary signal processing functions.

1. The data processing input has an 8x4 input crossbar mixer. This enables each input to be any ratio of the

eight input channels.

2. Two I2C programmable threshold detectors in each channel support auto mute.

3. Seven biquads per channel

4. Four soft bass and treble tone controls with ±18 dB range, programmable corner frequencies, and 2nd

order slopes. In 4-channel mode, bass and treble controls are normally configured as follows:

−

Bass and Treble 1: Channel 1 (Left), Channel 2 (Right), and Channel 3 (Center)

−

Bass and Treble 2: Channel 4 (Subwoofer)

5. Individual channel and master volume controls. Each control provides an adjustment range of +18 dB to

–127 dB. This permits a total volume device control range of +36 dB to –127 dB plus mute. The DAP soft

volume and mute update interval is I2C programmable. The update is performed at a fixed rate regardless

of the sample rate.

6. Programmable loudness compensation that is controlled via the combination of the master and individual

volume settings.

7. Two dual-threshold dual-rate dynamic range compressors (DRCs). The volume gain values are provided

used as input parameters using the maximum RMS (master volume x individual channel volume).

8. 4x2 output mixer (channels 1 and 2). Each output can be any ratio of any two signal processed channels.

9. 4x3 output mixer (channels 3 and 4). Each output can be any ratio of any three signal processed channels.

10. The DAP maintains three sets of coefficient banks that are used to maintain separate sets of sample rate

dependent parameters for the biquad, tone controls, loudness, and DRC in RAM. These can be set to be

automatically selected for one or more data sample rates or can be manually selected under I2C program

control. This feature enables coefficients for different sample rates to be stored in the TAS5504 and then

select when needed.

TAS5504 датащи(PDF) 17 Page - Texas Instruments

TAS5504 датащи(HTML) 17 Page - Texas Instruments

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 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96

датащи скачать

ссылки URL