D2-45057_14 Datasheet, PDF (29/31 Pages) Intersil Corporation – Intelligent Digital Amplifier PWM Controller and Audio Processor

D2-45057, D2-45157
COMPRESSORS AND LIMITERS
Two individual input compressors are included in the
input audio path, one for each of the two input channels.
Five output limiters are also included in the five output
path channels. The Compressor and Limiter blocks
operate identically, and their parameter settings allow
independent control of the audio signals. Typically, the
input path blocks are programmed to provide a
compression function, and the output path blocks are
programmed to limit output signal levels. But each can
be programmed as needed. Each Compressor/Limiter
has configurable Compression Ratio, Threshold, Attack
and Release Time, as well as Makeup Gain.
MULTI-BAND EQUALIZERS
Three sets of Multi-Band Parametric Equalizers are
included in the audio signal processing path. Each band
of the equalizers provides for independent gain,
frequency, and Q-factor programming.
A 5-Band Equalizer and a Speaker Equalizers (SEQ) are
included in both of the two input channels. Four 3-Band
Equalizers are also located in the four output channels.
STEREO ROUTER
A 4x4 stereo router is used to assign any one of the 4
input channel paths to each of the 4 output paths. The
router performs path assignment only. It does not have
provision for gain or signal level adjustment.
HIGH/LOW-PASS CROSSOVER FILTERS
High-Pass and Low-Pass filter blocks are provided for
each of the 5 output channels downstream of the Router
and Stereo Mixer. These provide a flexible Crossover
function for all the output channels, including provision
for defining the subwoofer channel’s frequency response.
The High and Low Pass blocks operate together, and are
implemented as a total of 4 cascaded elements, with 2
each of the elements allocated for High Pass, and the
other 2 elements allocated for Low Pass functionality.
Complete flexibility allows each element to be optionally
defined for either High or Low Pass. Each element is
selectable for a slope of 6, 12, 18, or 24dB, or may be or
bypassed. Three filter types of Butterworth, Bessel, or
Linkwitz-Riley implementations can also be chosen.
MASTER VOLUME CONTROL
A software-controlled Master Volume control is used to
adjust the global volume for all 5 output channels.
Master Volume operates a continuously adjustable
attenuator, from unity gain, down to -100dB and cutoff.
Each of the 5 output channels have their own dedicated
output level adjustments, providing individual channel
gain or attenuation after the output limiter stages.
Settings provide output level adjustment from +12dB to
-100dB.
LOUDNESS CONTOUR
An individual software-controlled Loudness Contour is
included for each of the 5 amplifier output channels. The
Loudness Contour curve is customized to allow for
dynamically and automatically enhancing the frequency
response of the audio program material relative to the
Master Volume Level setting. The Loudness Contour
models the frequency response correction as defined by
the Fletcher/Munson audio response curve. It provides
for amplitude or volume changes to those signals to
which the ear does not respond equally at very low
listening levels.
SOUNDSUITE™ PROCESSING
The D2Audio SoundSuite™ audio processing provides a
full set of enhancements to audio that greatly add to the
quality and listening experience of sound in wide scopes
of consumer devices. The D2Audio SoundSuite™
algorithms use psycho-acoustic processing that create a
rich-sounding environment from small speakers, and
synthesizes the sound and quality equivalent to more
complex systems. It is especially suited to consumer
products that include televisions, docking stations, and
mini hi-fi stereo products.
SoundSuite Processing Includes:
• D2Audio^® WideSound™
- An advanced Two-Channel Image Field
Enhancement
• D2Audio^® DeepBass™
- A sophisticated bass enhancement using
psycho-acoustics and Dynamic Filtering
• D2Audio^® AudioAlign™
- Sound Positioning and Alignment to the Video
Display
• D2Audio^® ClearVoice™
- Enhancement of Vocal Clarity
The D2Audio SoundSuite™ algorithms are completely
included within the D2-41051 DAE-4 devices.
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FN6785.0
July 29, 2010