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Doc.No. 20352 - 2 [Rev. July 2004]
GB3212 PRELIMINARY DATA SHEET
1 of 10
G
FEATURES
4-channel WDRC compression
16-band frequency shaping
16-band adaptive noise reduction
adaptive feedback cancellation
F
RONT
W
AVE
directional processing
high fidelity CODEC – dual A/D’s;D/A
16-bit DSP core processor
95dB input dynamic range with HRX Headroom
Extension
drives zero-bias 2-terminal receivers
thinSTAX packaging
4 fully configurable memories with audible memory
change indicator
2 memory select pads
internal/external volume control
AGCo with variable threshold and time constants
thin
STAX PACKAGING
Hybrid typical dimensions:
0.217 x 0.129 x 0.087in.
(5.51 x 3.28 x 2.21mm)
DESCRIPTION
DUET DIGITAL is a high end DSP system with advanced
adaptive algorithms. The signal processing algorithms run
on a hardware platform which is a combination of a high-
fidelity CODEC and a general purpose DSP core.
Algorithms developed and optimized by Gennum, running
on this powerful platform, offer true speech processing. The
reflowable thinSTAX packaging enables easy integration
into a wide range of applications, from CIC to BTE.
As shown in the block diagram below, some of the audio
DSP functions are implemented in hardware as a part of our
high fidelity CODEC while other adaptive algorithms such
as Noise Reduction and Feedback Cancellation use the
DSP core. Pre-processing blocks include
F
RONT
W
AVE
directional processing and programmable filters. Post-
processing blocks include tone generation, volume control,
AGCo and programmable filters.
The GB3212 hybrid code programmed into the EEPROM is
“40”.
This data sheet is part of a set of documents available for
this product. Please refer to
Getting Started with DUET
DIGITAL
, Document #29231 for a list of other documents.
BLOCK DIAGRAM
GND
SDA
MS2
N/A
N/A
MS1
FMIC
MGND
VREG
RMIC
T
OUT-
PGND
OUT+
VBP
VC
A/D
REGULATOR
CODEC
DSP
A/D
A/D
D/A
HBRIDGE
50n
60n
70n
70n
VC
VB
5
14
15
16
2
1
10n
EEPROM
FRONTWAVE
BIQUAD
FILTERS
AGC-O
BIQUAD
FILTERS
Frequency Shaping
16 bands
Noise Reduction
16 bands
TONE
GENERATOR
Frequency
Band
Analysis
Frequency
Band
Synthesis
band 1
Σ
band 16
WDRC
4 channels
Adaptive
Feedback
Cancellation
10
13
11
12
4
6
3
8
7
9
17
BIQUAD
FILTERS
DUET DIGITAL
Advanced DSP System
with
F
RONTWAVE