1
5
MPO
6
3
2
7
RPULL
V
B
A
IN
R1
48k
B
OUT
4
47n
8
C2
C1
3
3
5
7
8
6
GS3001
HYBRID
A
OUT
4
1
2
9
3
10
C4
C3
8a
V
MIC
C
IN
B
IN
PGND
MGND
R
MIC
-
A
-
B
GL504
47n
47n
DESCRIPTION
The GS3001 incorporates Gennum's GL504 preamp, all the
required coupling and decoupling capacitors, and a mid-
supply referencing 48 k
resistor. All that is required further
for a fully functioning hearing aid system is the addition of a
microphone, receiver, volume control and an MPO adjusting
potentiometer.
The GS3001 can be mounted on the back of the hearing aid's
battery compartment. It has several access pads allowing for
adjustment of the frequency characteristics. An additional
ground pad (8a) is also included to aid in the manufacturability
of the system.
The GL504 chip is Gennum's proprietary low current
preamplifier designed to drive class D integrated receivers.
This preamp has a built-in symmetrical peak clipping output
limiter and up to 46 dB of adjustable gain.
The major advantage of the GL504 over other preamplifiers is
the electronic MPO adjustment. Since conventional MPO is
not possible for integrated receivers, it is provided in the
preamp. The maximum output swing is easily set using an
R
MPO
resistor. The receiver output level is thus limited,
preventing it from exceeding the discomfort level.
GS3001 - HYB DATA SHEET
BLOCK DIAGRAM
FEATURES
designed to drive class D integrated receivers
adjustable peak clipper
low current drain (150
A typical)
46 dB of adjustable gain
low external parts required (R
VC
, R
MPO
)
low noise and distortion
mid supply referenced output
STANDARD PACKAGING
Hybrid typical dimensions
0.140 in. x 0.240 in. x 0.110 in.
(3.56 mm x 6.10 mm x 2.79 mm)
Preamp Hybrid for Class D
All resistors in ohms, all capacitors
in farads unless otherwise stated.
Revision Date: May 1998
Document No. 520 - 46 - 08
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
520 - 46 - 08
2
9
6
10
4
3
5
8
7
8a
2
1
A
IN
V
MIC
MGND
A
OUT
B
IN
MPO
V
B
B
OUT
PGND
C
IN
PGND
PARAMETER SYMBOL
CONDITION MIN TYP MAX UNITS
System Gain
A
V
V
IN
= -80 dBV, Frequency = 5 kHz
44.5
46.5
48.5
dB
Amplifier Current
I
AMP
V
IN
= 0, R
MPO
= 0
75
150
225
A
Maximum Output
MPO
V
IN
= -50 dBV, R
MPO
= 0
-16
-14
-12
dBV
MPO Range
MPO
V
IN
= -50 dBV, R
MPO
= 10 k
10
12
14
dB
Input Referred Noise
IRN
NFB at 200 Hz to 10 kHz
-
2
-
V
RMS
Distortion
THD
-
<1.0
-
%
On Chip Pull-up Resistance
R
PULL
-
48
-
k
On Chip Microphone Resistor
R
MIC
-
4
-
k
Mic Decoupling Capacitor
C1
-20%
3.3
+20%
F
Input Coupling Capacitor
C2
-10%
0.047
+10%
F
Interstage Coupling Capacitor
C3
-10%
0.047
+10%
F
Output Coupling Capacitor
C4
-10%
0.047
+10%
F
Output Resistor
R1
-5%
48
+5%
k
Output Impedance (Pad 9)
R
OUT
-
24
-
k
ABSOLUTE MAXIMUM RATINGS
PARAMETER
VALUE & UNITS
Supply Voltage
3 V DC
Power Dissipation
25 mW
Operating Temperature
-10 to + 40
C
Storage Temperature
-20 to +70
C
CAUTION
CLASS 1 ESD SENSITIVITY
PIN CONNECTION
ELECTRICAL CHARACTERISTICS
Conditions: Temperature 25
o
C, Frequency = 1 kHz.
(All conditions and parameters remain as shown in test circuit unless stated in condition column)
TOP VIEW
520 - 46 - 08
4
THD (%)
10
9
8
7
6
5
4
3
2
1
0
OUTPUT (dBV)
R
VC
= 3.3k
20
200
2k
20k
R
VC
= 100k
R
VC
= 33k
NO CAP.
C = 0.1
R
VC
= 10k
-140 -120 -100 -80 -60 -40 -20
Fig. 8
Output vs MPO Resistance
R
MPO
= 0
R
MPO
= 3.3k
R
MPO
= 10k
No Load
50k
Load
0 5 10 15 20 25 30
C = 0.47
-10
-14
-18
-22
-26
-30
-34
-38
-42
-46
-50
1 10 100 1k 10k 100k
-90 -86 -82 -78 -74 -70 -66 -62 -58
-100 -90 -80 -70 -60 -50 -40 -30 -20
-15
-25
-35
-45
-55
-65
-75
-85
-95
-10
Fig. 4 I/O for Various R
MPO
Settings
INPUT (dBV)
-10
-15
-20
-25
-30
-35
-40
-45
-50
Fig. 6 Distortion vs Input Level (R
VC
= 100 k
)
INPUT (dBV)
R
MPO
(
)
R
MPO
(k
)
Fig. 7 Quiescent Current vs MPO Resistance
0
-10
-20
-30
-40
-50
-60
-70
-80
-90
FREQUENCY (Hz)
Fig. 5 Frequency Response for Various C//C2 Values
INPUT (dBV)
Fig. 3 I/O for Various R
VC
Settings
2
0
-2
-4
-6
-8
-10
-12
-14
-16
-18
-20
OUTPUT (dBV)
OUTPUT (dBV)
RELATIVE OUTPUT (dB)
RELATIVE AMPLIFIER CURRENT (
A)
520 - 46 - 08
5
3001
XXXXXX
9
6
10
4
3
5
8
7
8a
2
1
C1
C3
C 4
C2
TOP VIEW
BOTTOM VIEW
0.240
(6.10 )
0.140
(3.56)
0.125 (MAX)
(3.18)
MPO TRIMMER
VOLUME CONTROL
BATTERY
MIC
+
REC
+
1
5
2
3
4
6
8
10
9
8a
7
- +
Fig. 9 Typical Assembly Diagram
Fig. 10 Hybrid Layout and Dimensions
Dimensioning units are inches.
Dimensions shown in parenthesis are
in millimetres,
converted from inches and include minor
round off errors.
1.0000 inches = 25.400mm
Pad size 0.045 x 0.025 (1.14 x 0.64)
Dimension tolerances
0.005 (+0.13)
unless otherwise stated.
XXXXXX - work order number.
Pad numbers and capacitor numbers for
illustration only.
DOCUMENT IDENTIFICATION:
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 September 1991 Gennum Corporation. All rights reserved. Printed in Canada.
REVISION NOTES:
Updated to Data sheet
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