Low Parts
Compression Amplifier
GB512/LD512 DATA SHEET
FEATURES
• 44 dB typical preamplifier gain
• 14 dB typical output stage gain
• compression function ratio 1:1 to 2:1 to
∞
:1
• automatic setting of transducer current
• operation down to 1.1 VDC
• greater than 40 dB volume control range
DESCRIPTION
The GB512 and LD512 are 8 pin stand-alone input compression
amplifiers requiring minimal external parts. Each consists of a
voltage regulator for the electret microphone providing a high
power supply rejection ratio (PSRR), a compression stage
which has a 2:1 compression ratio, and an auto-biasing,
class A, voltage drive output stage.
The auto-bias output stage can drive a variety of impedances
ranging from 500
Ω
to 5 kΩ without adding any external
resistors to set the bias.
The GB512 and LD512 are recommended for low to medium
gain/output ITE and ITC type hearing aids.
The GB512 is tested to tighter test limits.
STANDARD PACKAGING
•
8 pin PLID
•
8 pin SLT (LD512)
•
Chip (61 x 61 mils)
Au Bump
V
B
5
V
REG
4
V
REG
200 mV
REF
28 dB
16 dB
A IN
3
-
A
-
B
+
C
_
7
C OUT
CONTROL
2
C
AGC
6
GND
1
8
B OUT C IN
BLOCK DIAGRAM
Revision Date: January 2001
Document No. 500 - 75 - 08
GENNUM CORPORATION P.O. Box 489, Stn A, Burlington, Ontario, Canada L7R 3Y3 tel. (905) 632-2996 fax: (905) 632-5946
Japan Branch: A-302, Miyamae Village, 2-10-42, Miyamae, Suginami-ku, Tokyo 168, Japan
tel. (03) 3334-7700
fax (03) 3247-8839
GENNUM [ GENNUM CORPORATION ]
