FEATURES
• dual channel signal processing
• 2nd (4th) order state variable filter
• adjustable crossover frequency
• adjustable compression ratio from 1:1 to 4:1
• independent compression ratio adjustment for
low and high frequency band
• adjustable AGC threshold levels
• unique twin average detectors
• handles high input levels
• low THD and IMD distortion
• drives class D integrated receivers
• MPO range externally adjustable
PACKAGING
• Chip
Au Bump
DynamEQ® II
WDRC IC
GB570/GC570 - DATA SHEET
DEVICE DESCRIPTION
The DynamEQ® II product family is a second generation Wide
Dynamic Range Compression (WDRC) system.
GB570 (GC570) incorporates 12 dB/oct (24 dB/oct) filtering
and is designed to accommodate CIC and ITC size
requirements.
The gain and frequency response is dependant on the user’s
environment.
Twin averaging detector circuits are optimized for sound
quality during normal listening without sacrificing comfort
during sudden loud inputs.
All input signals to DynamEQ® II, are processed by 2:1
compression before subsequent band splitting.
The 12 dB/oct (24 dB/oct) band split filter ahead of the
expander/compressor circuits allows for independent
compression ratio adjustment (1:1 to 4:1) in high and low
frequency channels.
The gain setting stage is followed by a class D integrated
receiver preamplifier stage. Symmetrical peak clipping is used
to achieve MPO adjustment.
VB
18
VREG
8
REGULATOR
CSAD
7
CFAD
2
1M
SLOW
AVERAGE
DETECTOR
1M
FAST
AVERAGE
DETECTOR
1:1 2:1 4:1
1
6
5
85k6 42k8
RHI RLO
4
3
GB570
GC570
RTH 19
1
CONTROL
RECTIFIER
X
50k
RAGC_IN
11
IN
-A
10k
12 dB / Oct
(24 dB / Oct)
BAND SPLIT
FILTER
GND
9
12k
14k
10
12
13
All resistors in ohms, all capacitors
AOUT
REGIN
RÆ’c
in microfarads, unless otherwise stated
VB
RH
High Frequency
Expander / Compressor
48k
-B
-C
OUT
20
RL
Low Frequency
Expander / Compressor
48k
8k4
14 16
17
15 MPO
FOUT BIN
BOUT
FUNCTIONAL BLOCK DIAGRAM
Document No. 521 - 99 - 00
GENNUM CORPORATION P.O. Box 489, Stn. A, Burlington, Ontario, Canada L7R 3Y3 tel. +1 (905) 632-2996
Web Site: www.gennum.com E-mail: hipinfo@gennum.com