鈥?/div>
CIC suitable package size
low distortion compression limiting
38dB maximum system gain, adjustable over a
38dB range
output compression threshold, adjustable over
16dB range
2nd order active low cut filter adjustable from 530Hz
to 2.0kHz
designed to drive a class D integrated receiver
averaging detector
flexibility to add high cut filter
DESCRIPTION
The GS3044 CIC hybrid features AGC-O capability for low
distortion output limiting with an active low cut filter in a
package size suitable for CIC instruments. The circuit consists
of an AGC preamplifier and output stage, capable of driving
a class D integrated receiver. The compression control circuit,
connected between the input and output of the AGC
preamplifier, varies the current controlled resistance. It
operates with an 8:1 compression ratio and uses an averaging
detector with a time constant of 270ms, selected to provide
optimal sound quality over a full range of sound and listening
environments. The actual attack and release times are typically
40ms and 150ms respectively when the circuit is fully in the
compression region of operation (measured times vary
depending on gain and threshold settings).
The system gain, compression control and filter corner
frequency can be adjusted by choosing three independent
resistors or 100k trimmers. Maximum system gain is 38dB. It
can be adjusted within a 38dB range. The output compression
threshold can be adjusted within a 16dB range. The filter's
corner frequency can be adjusted from 530Hz to 2kHz.
GS3044
STANDARD PACKAGING
Hybrid typical dimensions:
0.180 x 0.110 x 0.070 in.
(4.57 x 2.79 x 1.78 mm)
V
B
1
R
VC
2
R
TH
3
C7
0碌15
GS3044
7
V
REG
C2
0碌1
REGULATOR
8:1
COMPRESSION
CONTROL
80k
RECT.
VB
48k
C1
C3
-F
15n
6n8
10k
12k
-A
B
48k
C8
10
OUT
33n
6
IN
C4
10n
800
C5
0碌1
R1 = 0
5
R
HP
8
All resistors in ohms, all capacitors
in farad, unless otherwidse stated.
C6
22n
9
4
GND
Note: R1 can be desoldered from hybrid to break connection between F
OUT
and A
IN
F
OUT
A
IN
BLOCK DIAGRAM
Revision Date: March 2000
Document No. 521 - 90 - 02
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
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