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ACOUSTIC ECHO CANCELLER WITH DUAL CODECS ZL38003
PRODUCT PREVIEW
Zarlink’s ZL38003 acoustic echo canceller is an integrated solution that
bundles high-quality algorithms with codecs to meet design cost, complexity
and integration issues for a wide range of hands-free communication systems.
Applications include car kits, speaker phones and intercom systems.
The ZL38003 chip deploys field-proven advanced adaptive algorithms designed to deliver exceptional performance in high background noise environments. The ZL38003 AEC’s integrated features, including codecs, programmable gain pads and a four-port cross-point switch eliminate the need for
many external components.
The chip supports full-duplex speech to provide clear signal transmission in
both audio path directions, even when signal levels are low. `Full-duplex operation prevents subjective sound quality problems associated with noise gating or noise contrasting to ensure clear speech and uninterrupted background
signals during conversation.
Performance and Features for
Hands-Free Communications
Full-duplex operation and adaptive
algorithm improve voice quality
Optimized to reduce noise in handsfree communications
Advanced NLP (non-linear
processor) design provides fullduplex speech with no switched
loss on audio paths
Integrated Codec
Two integrated DAC and ADC
codecs with analog gain pads
Mixed dual or single codec mode
Integrated four-port cross-point
switch allows analog signal to be
directed to any of four ports
ZL38003
Simplified Block Diagram
ZL38003 Simplified Block Diagram
Includes microphone and speaker
amplifiers
Acoustic Echo-Canceller
with Noise Reduction
Sin
Analog Input*
From Microphone
Gain
NLP
Comfort Noise
Injection
∑
Noise
Reduction
Sout
PCM Output
Gain
Analog Output
Control Unit
Acoustic
Echo Path
Up to +6 dB
Return Loss
CODEC
A
Adaptive
Filter
Howling Prevention
Double-Talk Detection
Narrow-Band
Network
Signal Protection
Gain
Rout
Analog Output
To Speaker
CODEC
B
Analog Input
User Gain
Rin
PCM Input
Serial Microprocessor Interface
High Quality Performance
Up to 12 dB of noise reduction
Fast re-convergence time quickly
tracks changing echo environment
Control of adaptive filter
convergence speed during periods
of double-talk, far end single-talk
and near-end echo path changes
Provides protection against narrowband signal divergence
Howling prevention stops
uncontrolled oscillation in high loop
gain conditions
Automatic gain control on the
receiver speaker path
Technical Support
Applications
Hands-free car kits
Intercom and pedestal systems
Speakerphones and
videoconference units
Security systems
The ZL38003 chip is supported by a
customer evaluation board, reference designs, online simulation tools and more.
Visit www.voiceprocessing.zarlink.com
ZL38003 ACOUSTIC ECHO CANCELLER WITH DUAL CODECS
APPLICATION
Hands-Free Car Kits
Desktop Phones
Zarlink Solution
Buyer Benefit
Zarlink Solution
Safety: Voice
Recognition (VR) allows
hands-free operation
Noise reduction enables reliable VR,
integrated codecs allow economical VR and
playback implementation
Sound Quality: Clear
sound, no echo
Noise reduction, full-duplex operation, AEC/
LEC algorithms
Convenience: In-car
audio system
Bluetooth, FM transmitter and audio
interfaces
Hands-free Operation:
Clear sound
Noise reduction eliminates background noise
Sound Quality: Clear
speech, reduced noise
Noise reduction and full-duplex operation enhance sound quality
Functionality: Cancel
echo in multi-size
rooms
No tuning required for room conditions,
programmable echo tail and patented NLP
ensure echo cancellation
Interfaces: Bluetooth,
VR, FM transmission
Bluetooth reference design, interfaces allow
use of off-the-shelf chips
Configuration:
Integrated approach
No ROM code required to initialize chip
Configuration: Easy to
install
Bluetooth, FM transmission for seamless
installation of car kits
Ergonomics
Algorithms tunable to different plastic
enclosures
Buyer Benefit
Desktop Phones
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Home Security System
Zarlink Solution
Security: Two-way
communications, faster
emergency service
Audio interface to DAA simplifies establishing
two-way communication
Privacy: Voice
communication
activated only by owner
Noise reduction improves VR
Reduce False
Dispatches: Eliminate
phone verification Improved quality enables direct voice
communication and voice enhancement
Sound Quality
AEC/LEC enhances sound quality
Cost Reduction/Ease
of Use
One chip replaces multiple components
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Micro Controller
Order Pedestal
Buyer Benefit
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Acoustic Echo Canceller
with Integrated Codecs
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Buyer Benefit
Zarlink Solution
Sound Quality: Clear
sound, no echo
Noise reduction, full-duplex operation =
improved customer service
Cost Reduction and
Design Ease
One chip with integrated codecs and
algorithms, supported by reference designs
and modules with discrete components
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Information relating to products and services furnished herein by Zarlink Semiconductor Inc. or its subsidiaries is believed to be reliable.
The products, their specifications, services and other information appearing in this publication are subject to change by Zarlink without notice.
ZARLINK, ZL, and the Zarlink logo are trademarks of Zarlink Semiconductor Inc.
© 2005, Zarlink Semiconductor Inc. All Rights Reserved.
Publication Number PP5924
www.ZARLINK.com