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PurePath™ Smart Amp User Manual (TAS5766M/68M)
5
1.3
What is Smart Amp?
Conventional hardware-based speaker protection matches the continuous power output of the
audio amplifier with the speaker output rating and sometimes incorporates high pass filtering to
prevent over-excursion.
PurePath™ Smart Amp
replaces hardware based speaker protection
methods with predictive algorithms, speaker characterization tools and real-time signal
monitoring to increase the peak output of the speaker without damage.
The first implementation step of
Smart Amp
based audio solutions is characterizing the speaker
with TI’s
PurePath™ Console 3
and the
PurePath™ Learning Board
. These are powerful, easy-
to-use tools designed specifically to simplify system level characterization, tuning and
implementation. The characterization process creates a digital model of the speaker based on
thermal, electro-mechanical and acoustic parameters.
The output of the characterization process is an initial set of coefficients that define the
Safe
Operating Area
(SOA)
which establishes the boundaries of maximum speaker diaphragm
excursion and voice-coil temperature during operation. If the
SOA
is set correctly, the audio
engineer need not worry about speaker damage during the audio tuning process – depending on
how hard the system is pushed audio might sound more or less desirable, but speaker safety is
ensured if configured properly.
EQ / Volume
Smart Bass
Protection
Amp
Smart Amp Control Algorithm
Automatic
bass response
alignment
Smart SOA
Smart Sense*
PurePath™
Smart Amp
Thermal,
Excursion
*Feedback systems
I/V, Supply,
Temperature
Helps keep
loudspeaker
within SOA
Audio
Input
Closed-loop
Class-D Amp
Smart EQ
Automatically
tunes high
frequencies
Figure 1. PurePath™ Smart Amp Block Diagram
PurePath™ Smart Amp
technology enables significant sound quality and system reliability
improvements while reducing component size and cost. The
PurePath™ Console 3
graphical
user interface and
Learning Board
speaker characterization hardware provide simple
configuration of advanced properties fully describing an audio system’s acoustical, electrical,
thermal and reliability capabilities and simplifying system level characterization, tuning and
integration.
