STA328

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and bass/treble tone control. Automodes™ enable a time-to-market advantage by substantially reducing

the amount of software development needed for certain functions. This includes Auto Volume loudness,

preset volume curves, preset EQ settings, etc. New advanced AM radio inerference reduction modes.

Three channels of DDX® processing are provided. This high quality conversion from PCM audio to DDX's

patented tri-state PWM switching waveform provides over 100dB SNR and dynamic range.

3

ORDERING INFORMATION

Figure 2. Block Diagram

Figure 3. Channel Signal Flow Diagram through the Digital Core

3.1 EQ Processing

Two channels of input data (re-sampled if necessary) at 96 kHz are provided to the EQ processing block.

In this block, upto 4 user-defined Biquads can be appplied to each of the two channels.

Pre-scaling, dc-blocking high-pass, de-emphasis, bass, and tone control filters can also be applied based

on various configuration parameter settings.

The entire EQ block can be bypassed for all channels simulatneously by setting the DSPB bit to '1'. And

the CxEQBP bits can be used to bypass the EQ functionality on a per channel basis. Figure below shows

the internal signal flow through the EQ block.

Serial Data

Input,

Channel

Mapping &

Resampling

DDX

®

Processing

Quad

Half-Bridge

Power Stage

OUT1A

OUT1B

OUT2A

OUT2B

LRCKI

SDI_12

SDA

SCL

PLL

CLK

EAPD

BICKI

FAULT

TWARN

Power-Down

I

System Contro

l

Audio EQ, Mix,

Crossver,

Volume, Limiter

Processing

System Timing

DDX-SPIRIT

Serial Data

Input,

Channel

Mapping &

Resampling

DDX

®

Processing

Quad

Half-Bridge

Power Stage

OUT1A

OUT1B

OUT2A

OUT2B

LRCKI

SDI_12

SDA

SCL

PLL

CLK

EAPD

BICKI

FAULT

TWARN

Power-Down

I

System Contro

l

Audio EQ, Mix,

Crossver,

Volume, Limiter

Processing

System Timing

DDX-SPIRIT

Channel

Mapping

Re-sampling

EQ

Processing

Mix

Volume

Limiter

4X

Interp

I

Input

DDX

Output

Crossover

Filter