Datasheet GS551 Datasheet (Gennum Corporation)

High Power, Class B

Output Stage

GS551 DATA SHEET

FEATURES

• adjustable gain to 48 dB

• capable of driving low impedance receiver

• low component count, 3 small capacitors and 1 resistor

• gain trim can be used as vol. control for reduced noise

• minimal start-up transient

• no gain expansion

STANDARD PACKAGING

• 10 pin MICROpac

• 10 pin PLID

®

• 10 pin SLT

• Chip (68 x 60 mils)

CIRCUIT DESCRIPTION

The GS551 is a 10 pin, low voltage, class B amplifier which
operates over a battery range of 1.1 VDC to 3 VDC.

The GS551 consists of three gain blocks. The first block is
an inverting amplifier with the gain set by two external
resistors. The gain trim feature can be used as a volume
control in hearing aid applications. The second block is an
inverting unity gain amplifier which serves as a phase
splitter. The outputs from the first and second blocks drive
the differential input of the third block. The third block has
a fixed AC gain of 28 dB when driving a receiver.

The amplifier has internal compensation eliminating the
need for a capacitor across the receiver. Two ground pins
are available for “Star” grounding to reduce any second
order harmonic distortion introduced by ground line resistance.

V

B

6

10

C OUT 2

1

C OUT 1

3

A IN

A OUT

4

U.S. Patent No. 4,719,430
Other Patents Pending

5

- A

29

GND 1

- B

REFERENCE

VOLTAGE

GND 2

C

7

VREF DEC 1

8

DEC 2

BLOCK DIAGRAM

Revision Date: January 2001

GENNUM CORPORATION P.O. Box 489, Stn. A, Burlington, Ontario, Canada L7R 3Y3 tel. [phone]

Web Site: www.gennum.com E-mail: [e-mail]

Document No. 510 - 31 - 04

ABSOLUTE MAXIMUM RATINGS

PIN CONNECTION

PARAMETER VALUE/UNITS

Supply Voltage 5 VDC
Operating Temperature -10 to +40 °C
Storage Temperature -20 to +70 °C

CAUTION

A IN

A OUT

DEC 1

GND 1

C OUT 1

5

VB

6

VREF
DEC 2
GND 2

101

COUT 2

CLASS 1 ESD SENSITIVITY

ELECTRICAL CHARACTERISTICS

Conditions: Frequency = 1 kHz, Temperature = 25°C, Supply Voltage V

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

= 1.3 VDC

B

Gain A

Amplifier Current I

Transducer Current I

V

AMP

TRANS

VO=0.707 VRMS 46 48 50 dB

120 220 335 µA
120 250 390 µA

Input Referred Noise IRN NFB 0.2 to 10 kHz at 12 dB/Oct - 1.3 2.5 µV

Total Harmonic Distortion VO=0.707 VRMS - 0.25 1.3 %

THD

VO=1.3 VRMS - 0.3 1.5 %

Stable with RB to R

Maximum Output Current I

All parameters remain as shown in Test Circuit unless otherwise stated in "Conditions" column

C

R

S

S

10k

0.1

STAB

OUT

5

- A

100k

RB=22Ω - - 22 Ω

VP8=0 - >35 - mA

= 1.3VDC

V

B

6

10

RB = 4.7

I

OUT

V

O

- B
C

RL = 400

510 - 31 - 04

1 kHz

4

All resistors in ohms,all capacitors in farads
unless otherwise stated

REFERENCE

VOLTAGE

1

29783

0.047

0.047

Fig. 1 Test Circuit

2

7

6

4

Base Current

Compensation

2

5

6

1

10

REGULATOR

+
_

4

0.1

30k

R

S

3.9k

3

4.7
2

0.1

230

1

1.0

R

GT

50k

All resistors in ohms,all capacitors in farads unless otherwise stated

5

8

Fig. 2 GS551 Functional Schematic

10k

R

VC

100k

5

- A

4

2

3

2

9

1.3 VDC

6

10

- B

REFERENCE

VOLTAGE

C

1

CI2960

GS551LC506

9783

0.047

0.047

Fig. 3 Application Circuit

3

510 - 31 - 04

10

0

-10

-20

-30

-40

-50

-60

OUTPUT (dBV)

-70

-80

-90

-130 -120 -110 -100 -90 -80 -70 -60 -50 -40 -30 -20 -10

RVC=100k

RVC=47k

RVC=22k

RVC=10k

RVC=3.3k

INPUT (dBV)

Fig. 4 I/O Characteristics at Various

Gain Settings (RS=3.92k)

14
13
12
11
10

9
8
7
6
5
4
3

POWER OUTPUT (mW)

2
1
0

0 100 200 300 400 500 600 700 800 900 1000

LOAD RESISTANCE (Ω)

Fig. 6 Power Outout vs Load Resistance
at 7% Distortion, RB=0Ω, VB=1.35V

0.10

0.08

0.06

0.04

0.02

0

-0.02

-0.04

RELATIVE GAIN (dB)

-0.06

-0.08

-0.10

-20 -10 0 10 20 30 40 50

TEMPERATURE (°C)

Fig. 8 Gain vs Temperature

4
2

CS=0.22 µF

0

-2
CS=0.1 µF

-4

-6

-8

-10

-12

-14

-16

RELATIVE OUTPUT (dB)

-18

-20
20 200 2k 20k

CS=0.047 µF

CS=0.033µF

FREQUENCY (Hz)

Fig. 5 Closed Loop Frequency Response
at Various CS Values (RS=3.92k)

10

5
0

-5

-10

-15

-20

-25

-30

-35

RELATIVE GAIN (dB)

-40

-45

-50
.8 .9 1 1.1 1.2 1.3 1.4

SUPPLY VOLTAGE (VDC)

Fig. 7 Gain vs Supply Voltage

50
40
30
20
10

0

-10

-20

-30

-40

-50

-60

RELATIVE AMPLIFIER CURRENT (µA)

-70

-20 -10 0 10 20 30 40 50

TEMPERATURE (°C)

Fig. 9 Amplifier Current vs Temperature

GENNUM CORPORATION

MAILING ADDRESS:
P.O. Box 489, Stn. A, Burlington, Ontario, Canada L7R 3Y3
Tel. [phone] Fax [phone]
SHIPPING ADDRESS:
970 Fraser Drive, Burlington, Ontario, Canada L7L 5P5

GENNUM JAPAN CORPORATION

C-101, Miyamae Village, 2-10-42 Miyamae, Suginami-ku, Tokyo 168-0081,

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:

Changes to standard packaging information.

Japan Tel. [phone] Fax: [phone]

Gennum Corporation assumes no responsibility for the use of any circuits described herein and makes no representations that they are free from patent infringement.

510 - 31 - 04

© Copyright August 1988 Gennum Corporation. All rights reserved. Printed in Canada.

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