GENNUM LD512

Low Parts
Compression Amplifier
GB512/LD512 DATA SHEET
DESCRIPTION
FEATURES
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.
• 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
• greater than 40 dB volume control range
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.
STANDARD PACKAGING
The GB512 and LD512 are recommended for low to medium
gain/output ITE and ITC type hearing aids.
• 8 pin PLID
The GB512 is tested to tighter test limits.
• operation down to 1.1 VDC
• 8 pin SLT (LD512)
• Chip (61 x 61 mils)
Au Bump
VB
5
VREG
4
28 dB
A IN
3
200 mV
REF
VREG
-A
16 dB
+
C
_
- B
7
C OUT
CONTROL
2
6
CAGC
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
PIN CONNECTION
ABSOLUTE MAXIMUM RATINGS
PARAMETER
VALUE/UNITS
5 V DC
VREG
25mW
A IN
-10°C to 40°C
CAGC
-20˚C to 70˚C
B OUT
Supply Voltage
Power Dissipation
Operating Temperature Range
Storage Temperature Range
5
4
VB
GND
C OUT
1
C IN
8
CAUTION
CLASS 1 ESD SENSITIVITY
ELECTRICAL CHARACTERISTICS
Conditions : Temperature 25˚C, Frequency 1 kHz, Supply Voltage 1.3 VDC.
PARAMETER
SYMBOL
GB512
CONDITIONS
LD512
MIN
TYP
MAX
MIN
TYP
MAX
200
290
110
200
290
UNITS
µA
Amplifier Current
IAMP
110
Regulator Voltage
VREG
0.88
0.93
0.98
0.88
0.93
0.98
VDC
Output Level
VO1
VIN = -88 dBV
-47
-44
-41
-48
-44
-40
dBV
Output Level
VO2
VIN = -74 dBV
VO1 + 7 VO1 + 9 VO1 + 11
-
-
-
dB
Output Level
VO3
VIN = -54 dBV
VO2 + 8 VO2+10
VO2+10
VO2+13
dB
Output Level
VO4
VIN = -40 dBV
Input Referred Noise
IRN
Total Harmonic Distortion
VO2+12 VO2 + 7
-23
-20
-18
-23.5
-20
-17.5
dBV
NFB 0.2-10kHz at 12dB/oct
-
1
3
-
1
3
µVRMS
THD
VIN = -54 dBV
-
2
4
-
2
4
%
Receiver Bias Voltage
VBIAS
Note 3
100
200
300
160
200
240
mVDC
Current Sinking Capability
ISINK
Note 4
3
8
-
3
8
-
mA
Release Time Factor
TREL
-
100
-
-
100
-
ms/µF
Attack Time Factor
TATT
-
5
-
-
5
-
ms/µF
All parameters and switches remain as shown in the Test Circuit unless stated in CONDITIONS column.
VPX - actual voltage measured on the pin at given condition (X is pin number).
VO4
Notes:
1. VO and Distortion measurements are taken
at pin 1.
VO3
2. Output stage gain = 20 log (RF / RS).
O/P
LEVEL VO2
(dBV)
at PIN 1
A gain of 14 dB is recommended for
optimal stability. Stability is dependent
upon the ratio of the receiver impedance
VO1
(Z L) and the battery impedance to RF & RS.
(RF / RS) < (ZL/ RB)
-88 dBVIN
-74 dBVIN
-54 dBVIN
-40 dBVIN
3. VBIAS = VP5 - VP7
4. Measured at pin 7
500 - 75 - 08
2
RB
IAMP
VB= 1.3 VDC
4Ω7
5
2k2
4
200 mV
REF
VREG
1µ0
16 dB
28 dB
3
3k9
-A
+
C
_
- B
0µ1
7
VIN
CONTROL
6
2
1
8
RF
0µ1
1µ0
22k
VO
100k
All resistors in ohms, all capacitors
in farads unless otherwise stated
Fig. 1 Test Circuit
5
7
8
4
REGULATOR
1
BASE CURRENT
COMPENSATION
3
6
_
CONTROL
_
1k
120k
2
Fig. 2 Functional Schematic
3
500 - 75 - 08
VB=1.3 VDC
5
ED1913
4
200 mV
REF
VREG
1µ0
RS
3k9
16 dB
28 dB
CS
3
-A
+
C
_
- B
0µ1
7
CONTROL
1
6
2
8
1µ0
0µ1
20K
100k
RVC
All resistors in ohms, all capacitors
in farads unless otherwise stated
Fig. 3 Typical Hearing Aid Application
0
0
RVC = 100k
-10
-10
RVC = 47k
-20
RVC = 22k
OUTPUT (dBV)
OUTPUT (dBV)
-20
-30
-40
-50
RVC = 3.3K
-60
-30
-40
-50
-60
RVC = 10K
-70
-70
-80
-100
-90
-80
-70
-60
-50
-80
-100
-40
-90
-80
-70
-60
-50
INPUT (dBV)
INPUT (dBV)
Fig. 4 I/O Characteristics at Various
RVC Values (Pin 7)
Fig. 5 I/O Characteristics at Pin 1
-40
5
4
2
-2
CS = 0.1µF
-4
RELATIVE GAIN (dB)
RELATIVE OUTPUT (dB)
0
CS = 0.22µF
0
CS = 0.033µF
-6
CS = 0.047µF
-8
-10
-12
-5
-10
-15
-20
-14
-16
-25
-18
-20
-30
20
200
FREQUENCY
2K
0.7
20K
0.9
1.0
1.1
1.2
SUPPLY VOLTAGE (VDC)
Fig. 6 Closed Loop Frequency Response
at Various CS Values
500 - 75 - 08
0.8
Fig. 7 Gain vs Supply Voltage
4
1.3
1.4
RELATIVE REFERENCE VOLTAGE (mVDC)
1.4
1.2
RELATIVE GAIN (dB)
1.0
0.8
0.6
0.4
0.2
0.0
-0.2
-0.4
-0.6
-0.8
-1.0
-20
-10
0
10
20
30
40
30
20
10
0
-10
-20
-30
-40
-50
50
-20
-10
0
10
20
30
40
50
TEMPERATURE (˚C)
TEMPERATURE (˚C)
Fig. 8 Gain vs Temperature
Fig. 9 Receiver Bias Voltage vs Temperature
RELATIVE AMPLIFIER CURRENT (µA)
50
40
30
20
10
0
-10
-20
-30
-40
-50
-60
-70
-20
-10
0
10
20
30
40
50
TEMPERATURE (˚C)
Fig. 10 Amplifier Current vs Temperature
REVISION NOTES
Changes to standard packaging information.
DOCUMENT
IDENTIFICATION
PRODUCT PROPOSAL
This data has been compiled for market investigation purposes
only, and does not constitute an offer for sale.
ADVANCE INFORMATION NOTE
This product is in development phase and specifications are
subject to change without notice. Gennum reserves the right to
remove the product at any time. Listing the product does not
constitute an offer for sale.
PRELIMINARY DATA SHEET
The product is in a preproduction phase and specifications are
subject to change without notice.
DATA SHEET
The product is in production. Gennum reserves the right to make
changes at any time to improve reliability, function or design, in
order to provide the best product possible.
Gennum Corporation assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement.
© Copyright Sept. 1982 Gennum Corporation.
All rights reserved. Printed in Canada.
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500 - 75 - 08