ETC GS3001

Preamp Hybrid for Class D
GS3001 - HYB DATA SHEET
FEATURES
DESCRIPTION
• designed to drive class D integrated receivers
The GS3001 incorporates Gennum’s GL504 preamp, all the
required coupling and decoupling capacitors, and a midsupply referencing 48 kΩ 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.
• adjustable peak clipper
• low current drain (150 µA typical)
• 46 dB of adjustable gain
• low external parts required (R
, RMPO)
VC
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.
• low noise and distortion
• mid supply referenced output
STANDARD PACKAGING
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.
• 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)
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
RMPO resistor. The receiver output level is thus limited,
preventing it from exceeding the discomfort level.
VMIC
6
3
10 VB
RPULL
C4
-B
-A
2
47n
CIN
7
C1
3µ3
C2
AIN
RMIC
9 BOUT
8
5
47n
R1
48k
1
GL504
3
4
2
1
MGND 4
C3
GS3001
HYBRID
All resistors in ohms, all capacitors
in farads unless otherwise stated.
47n
5
AOUT
6
BIN
8a
8
PGND
7
MPO
BLOCK DIAGRAM
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: [email protected]
PIN CONNECTION
ABSOLUTE MAXIMUM RATINGS
PARAMETER
CIN
VALUE & UNITS
Supply Voltage
3 V DC
Power Dissipation
25 mW
Operating Temperature
-10 to + 40 °C
Storage Temperature
-20 to +70 °C
AIN
2
VMIC
10
VB
3
9
BOUT
MGND
4
8a
PGND
AOUT
5
8
PGND
1
BIN
CAUTION
7
6
TOP VIEW
MPO
CLASS 1 ESD SENSITIVITY
ELECTRICAL CHARACTERISTICS
Conditions: Temperature 25 oC, Frequency = 1 kHz.
PARAMETER
SYMBOL
CONDITION
MIN
TYP
MAX
UNITS
44.5
46.5
48.5
dB
System Gain
AV
VIN = -80 dBV, Frequency = 5 kHz
Amplifier Current
IAMP
VIN = 0, RMPO = 0 Ω
75
150
225
µA
Maximum Output
MPO
VIN = -50 dBV, RMPO = 0 Ω
-16
-14
-12
dBV
MPO Range
∆MPO
VIN = -50 dBV, RMPO = 10 kΩ
10
12
14
dB
Input Referred Noise
IRN
NFB at 200 Hz to 10 kHz
-
2
-
µVRMS
Distortion
THD
-
<1.0
-
%
On Chip Pull-up Resistance
RPULL
-
48
-
kΩ
On Chip Microphone Resistor
RMIC
-
4
-
kΩ
Mic Decoupling Capacitor
C1
-20%
3.3
+20%
µF
Input Coupling Capacitor
C2
-10%
0.047
+10%
µF
Interstage Coupling Capacitor
C3
-10%
0.047
+10%
µF
Output Coupling Capacitor
C4
-10%
0.047
+10%
µF
Output Resistor
R1
-5%
48
+5%
kΩ
Output Impedance (Pad 9)
ROUT
-
24
-
kΩ
(All conditions and parameters remain as shown in test circuit unless stated in condition column)
520 - 46 - 08
2
6
3
RMIC
C1
3µ3
3k9
10
IAMP
RPULL
C2
5
9
8
47n
VIN
R1
48k
1
1kHz
GL504
3
4
4
2
1
VOUT
C4
-B
-A
2
47n
VB = 1.3 VDC
7
C3
GS3001
HYBRID
47n
5
8a
6
8
7
RMPO =10k
RFA =100k
All resistors in ohms, all capacitors
in farads unless otherwise stated.
Fig. 1 Production Test Circuit
1.3 VDC
3
6
7
C1
3µ3
2
5
47n
10
RPULL
C2
MIC
RMIC
C4
-B
-A
CLASS D
RECEIVER
9
8
47n
1µ
R1
48k
1
GL504
3
4
4
2
1
C3
GS3001
HYBRID
47n
5
6
RFA =100k
8a
8
7
RMPO =10k
All resistors in ohms, all capacitors
in farads unless otherwise stated.
Fig. 2 Typical Hearing Instrument Application
3
520 - 46 - 08
-10
-10
-15
RVC = 100k
-15
R
MPO
R
= 33k
VC
-45
RVC = 10k
-55
-65
R
-75
VC
= 3.3k
RMPO = 3.3k
-25
RMPO = 10k
-30
-35
-40
-85
-45
-95
-140
-120
-100
-80
-60
-40
-50
-100
-20
-90
-80
INPUT (dBV)
-50
-40
-30
-20
10
0
C = 0.47µ
9
-2
8
-4
THD (%)
RELATIVE OUTPUT (dB)
-60
Fig. 4 I/O for Various RMPO Settings
2
-6
-8
C = 0.1µ
-10
7
6
5
4
-12
3
-14
2
-16
NO CAP.
-18
1
0
-90
-20
20
200
2k
20k
-86
-82
-78
-74
-70
-66
-62
-58
INPUT (dBV)
FREQUENCY (Hz)
Fig. 6
Fig. 5 Frequency Response for Various C//C2 Values
0
-10
-10
-14
Distortion vs Input Level (RVC = 100 kΩ)
No Load
-18
-20
-30
OUTPUT (dBV)
RELATIVE AMPLIFIER CURRENT (µA)
-70
INPUT (dBV)
Fig. 3 I/O for Various RVC Settings
-40
-50
-60
-22
50kΩ Load
-26
-30
-34
-38
-70
-42
-80
-46
-50
-90
0
5
10
15
20
25
30
1
10
100
1k
10k
(kΩ)
MPO
R MPO (Ω)
Fig. 7 Quiescent Current vs MPO Resistance
Fig. 8 Output vs MPO Resistance
R
520 - 46 - 08
= 0Ω
-20
-35
OUTPUT (dBV)
OUTPUT (dBV)
-25
4
100k
VOLUME CONTROL
2
MIC
+
1
10
+
3
9
4
8a
REC
5
7
+
8
6
BATTERY
MPO TRIMMER
Fig. 9 Typical Assembly Diagram
TOP VIEW
2
10
1
3
9
3001
0.140
(3.56)
XXXXXX
8a
4
5
7
6
8
0.240
(6.10 )
0.125 (MAX)
(3.18)
BOTTOM VIEW
C4
C1
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.
C2
C3
Fig. 10 Hybrid Layout and Dimensions
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.
REVISION NOTES:
Updated to Data sheet
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.
5
Printed in Canada.
520 - 46 - 08