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Zarlink Semiconductor Inc.
Zarlink, ZL and the Zarlink Semiconductor logo are trademarks of Zarlink Semiconductor Inc.
Copyright 2004-2010, Zarlink Semiconductor Inc. All Rights Reserved.
Zarlink has introduced a new generation family of
AEC (ZL38002 and ZL38004). Zarlink recommends
these products for new designs.
Features
• Contains two echo cancellers: 112 ms acoustic
echo canceller + 16 ms line echo canceller
• Works with low cost voice codec. ITU-T G.711 or
signed mag /A-Law, or linear 2’s comp
• Each port may operate in different format
• Advanced NLP design - full duplex speech with
no switched loss on audio paths
• Fast re-convergence time: tracks changing echo
environment quickly
• Adaptation algorithm converges even during
Double-Talk
• Designed for exceptional performance in high
background noise environments
• Provides protection against narrow-band signal
divergence
• Howling prevention stops uncontrolled oscillation
in high loop gain conditions
• Offset nulling of all PCM channels
• Serial micro-controller interface
• ST-BUS, GCI, or variable-rate SSI PCM interfaces
• User gain control provided for speaker path
(-24dB to +48dB in 3dB steps)
• 18 dB gain at Sout to compensate for high ERL
environments
• AGC on speaker path
• Handles up to 0 dB acoustic echo return loss
• Transparent data transfer and mute options
• 20 MHz master clock operation
• Low power mode during PCM Bypass
• Bootloadable for future factory software upgrades
• 2.7 V to 3.6 V supply voltage; 5 V tolerant inputs
September 2010
Ordering Information
ZL38001QDG1 48 Pin TQFP* Trays, Bake & Drypack
ZL38001DGF1 36 Pin SSOP* Tape & Reel,
Bake & Drypack
ZL38001DGE1 36 Pin SSOP* Tubes, Bake & Drypack
*Pb Free Matte Tin
-40C to +85C
ZL38001
AEC for Analog Hands-Free
Communication
Data Sheet
Figure 1 - Functional Block Diagram
Rout
MD1
MD2
PORT 2
Sin
Line ECho Path
S
1
Micro
Interface
Program
RAM
Program
ROM
FORMAT
Linear/
/A-Law
Offset
Null
Linear
/A-Law/
Linear/
/A-Law
Adaptive
Filter
Offset
Null
VDD
VSS
RESET
F0i
BCLK/C4i
MCLK
Sout
Rin
DATA1
DATA2
CS
SCLK
ENA2
LAW
AGC
User
Gain
+
-
ADV
+
-
-24 -> +21 dB
R
1
R
2
R
3
S
2
S
3
NLP
ADV
NLP
Linear
/A-Law/
+
+
Howling
Controller
PORT 1
NBSD
Adaptive
Filter
UNIT
CONTROL
Detector
Talk
Double
NBSD
ENA1
Limiter
Limiter
ACOUSTIC ECHO PATH
18dB
Gain
