GA3216 Datasheet, PDF (1/14 Pages) Gennum Corporation – FOUNDATION-TM Digital Single or Dual Channel DSP Compression System

FEATURES
• efficient, high fidelity 1 or 2-channel WDRC signal
processing
• fully programmable via serial data interface
• SOUNDDESIGN™ high-fidelity audio quality
• four trimmer inputs plus volume control
• flexible trimmer/parameter assignments
• optional two-terminal or three-terminal trimmers
• choice of wideband or independent 2-channel level
detection
• choice of two strategies for AGC-I parametric
adjustment
• 6, 12 or 24 dB/octave band split filter or configurable
as single-channel compressor.
• in-channel, low level squelch control (1:2 expansion)
• output compression limiting (AGC-O)
• flexible pre- and post-emphasis filters
• four independent memories
• pulse-density-modulated output stage drives zero-
bias 2-terminal receivers
thinSTAX™ PACKAGING
Hybrid typical dimensions:
0.190 x 0.123 x 0.060in
(4.82 x 3.12 x 1.52mm)
FOUNDATION™ Digital
Single or Dual Channel
DSP Compression System
GA3216 PRELIMINARY DATA SHEET
DESCRIPTION
The GA3216 hybrid is a trimmer-configurable DSP system
based on a two-channel compression circuit. It can
efficiently replace traditional hearing-aid compression
circuits without compromising fundamental performance
requirements.
A trimmer interface supports manual circuit configuration. It
continuously monitors trimmer positions and translates them
into the hearing-aid parameters of choice. A serial data
interface provides full programmability both at the factory
and in the field.
The GA3216 includes in-channel squelch to attenuate
microphone and circuit noise in quiet environments. It also
includes low-distortion compression limiting and
programmable high and low cut filters as well as five
configurable equalization filters. Unused blocks can be
powered down to save battery current, for example, when
using the device in single-channel mode.
The GA3216 Hybrid code programmed into the GC5020
controller chip is '1'.
This datasheet is part of a set of documents available for
this product. Please refer to Getting Started with Foundation
Digital, document #25786 for a list of other documents.
VREG2 19
VREG ¹
IN ¹⁶
T 17
REGULATOR
A/D
MGND 15
GA3216
MS2
MS
14
13
SDA
12
PROGRAMMING
INTERFACE
EEPROM
TWIN DETECTOR
T-coil EQ
1st to 3rd
ORDER
LC
HP
24db/oct
BAND SPLIT
FILTER
LP
COMPRESSOR
TWIN DETECTOR
SQUELCH
COMPRESSOR
TWIN DETECTOR
SQUELCH
TRIMMER INTERFACE
1st or 2nd
Σ
ORDER
HC
EQ1
EQ2
EQ3
5
2
3
4 18
VC TR1 TR2 TR3 TR4
BLOCK DIAGRAM
VB
11
TONE
GENERATOR
EQ5
EQ4
AGC-O
TWIN DETECTOR
VC GAIN
10 ^VBP
PEAK
CLIPPING
D/A
HBRIDGE
8 OUT+
9 OUT -
7 _PGND
20
GND2
6
GND1
Doc.No.24501 - 3 [Rev. February 2004]
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