Gennum Corporation GM3008 Datasheet

Stand Alone

Class B Hybrid

GM3008 - HYB DATA SHEET

FEATURES

• up to 80 dB of electrical gain

• dedicated preamp for a telecoil

• direct coupling of a telecoil to preamp

• low input referred noise

• on chip voltage regulator

• capable of driving low impedance receivers

STANDARD PACKAGING

• Hybrid typical dimensions

0.250 in x 0.150 in x 0.115 in
(6.35 mm x 3.81 mm x 2.92 mm)

DESCRIPTION

The GM3008 hybrid consists of two of Gennum's proprietary
integrated circuits, the GP537 preamplifier and the GS551
class B output driver. Such a configuration provides up to
80 dB (typ) of electrical gain. Low total harmonic distortion
and input noise make this circuit well suited for high power
applications. Various additional pads have been provided
to allow for maximum flexibility of system performance.

The GP537 contains two low noise inverting preamplifiers
with an open loop voltage gain of typically 50 dB, a telecoil
preamplifier with its own reference voltage which enables
for direct coupling of the telecoil and a voltage regulator
with typically 74 dB of supply rejection capable of working
with a supply voltage down to 1.1 volts. This chip also
enables the user to disconnect the telecoil preamplifier
when it is not required, thereby saving approximately
85 µA of current.

The GS551 class B amplifier contains three basic blocks,
a low noise inverting preamplifier, a unity gain phase
splitter and a fixed gain class B output stage.

V

REG

11

C1

V

BT

T

REF

T

IN

T

OUT

INPUT

MGND

Revision Date: May 1998

3µ3

16
15

14

13
10

12

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

C2
47n

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

5

B

OUT

GM3008

R4 15k

C3 47n

8

9

C

GS551

5

-

C

2

4

R5
60k

65

C

F

IN

C

OUT

-

D

REFERENCE

VOLTAGE

9

1

PGND

6

1

4

OUT 1

3

2

V

CC

OUT 2

E

10

7

C4
47n

C5
47n

3

8

3
2

4

REGULATOR

GP537

+

-

1

11

-

T

9

R1
18k2

-

A

8

10

R2
105k

17

A

IN

18

A

OUT

7

R3
20k

-

B

6

7

B

IN

FUNCTIONAL BLOCK DIAGRAM

Document No. 520 - 70 - 05

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

ABSOLUTE MAXIMUM RATINGS

PAD CONNECTION

PARAMETER VALUE / UNITS

Supply Voltage 3 VDC
Power Dissipation 25 mW
Operating Temperature Range -10° C to 40° C
Storage Temperature Range -20° C to 70° C

1

2

16

3

6

18

17

4

8

5

7

ELECTRICAL CHARACTERISTICS

Conditions: Frequency = 1 kHz, Temperature = 25°C, Supply Voltage VCC = 1.3 V Notes:1. All capacitors on hybrid ±20%, all printed on resistors ±5%

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

Amplifier Current I
Telecoil Current I
Transducer Current I

AMP
TCOIL
TRANS

REGULATOR

Regulator Voltage V

REG

Regulator Supply Rejection PSRR 60 74 - dB

T COIL

Bias Voltage V
Telecoil Offset Voltage V
Input Bias Current I
Output Voltage Swing - Low V
Maximum Sourcing Current I
Open Loop Voltage Gain A

BIAS
TOFF

BIAS

OL

SOURCE

VOL

STAGES A & B

Bias Voltage V
Input Bias Current I
Output Voltage Swing - Low V
Maximum Sourcing Current I
Open Loop Voltage Gain A

BIAS

BIAS

OL

SOURCE

VOL

STAGE C

Bias Voltage V
Input Bias Current I
Output Voltage Swing - Low V
Maximum Sourcing Current I
Open Loop Voltage Gain A

BIAS

BIAS

OL

SOURCE

VOL

STAGE D

Voltage Gain GAIN - 0 - dB

STAGE E

AC Voltage Gain GAIN - 28 - dB
Maximum Sourcing Current I

SOURCE

SYSTEM PERFORMANCE

System Voltage Gain S
Telecoil Gain T

GAIN
GAIN

Total Harmonic Distortion THD VIN = -60dB, RF = 39k - 3 5 %
Input Referred Noise IRN - 2.5 - µV

All parameters and switches remain as shown in the Test Circuit unless otherwise stated in CONDITIONS column.

520 - 70 - 05

S1 = Open 190 365 550 µA

40 85 130 µA

Quiescent Current VIN = 0 V 100 250 390 µA

0.88 0.93 0.98 V

Pads 13, 14 540 580 620 mV
V

P15

- V

P14

-10 0 10 mV

-25 0 25 nA

200 280 - mV

15 30 - µA
46 50 - dB

Pads 7, 9, 17, 18 540 580 620 mV

-25 0 25 nA

200 280 - mV

15 30 - µA
46 50 - dB

Pads 5, 6 540 580 620 mV

-0 -nA

- 280 - mV

-50 -µA

-50 -dB

- >35 - mA

VIN = -60 dBV, RF = 39k 56 60 64 dB
S2 = b; VIN = -60 dBV 16 18.5 20 dB

2

131415

12

11

10

9

V

IN

(0V AC)

GM3008

GS551

5

-

C

B

5

2

-

D

REFERENCE

VOLTAGE

4

9

6

1

E

10

7

3

8

1.3 VDC

4

3

I

AMP+ITCOIL

2

I

TRANS

V

OUT

390

C4

R4 15k

C3 47n

9

R5
60k

8

6

5

47n

C5
47n

1

C1
3µ3

3

2

+

-

1

11

-

T

10

9

11

S1

16
15

1µ

14

10k

1k

REGULATOR

-

A

8

4

R2

13

S2

b
a

C2

10

47n

12

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

R1
18k2

105k

17

GP537

-

7

6

R3
20k

7

18

RF=390k

Fig. 1 Production Test Circuit

MIC
EK3024

C1
3µ3

3
2

+

-

1

11

-

11

16
15

14

10k

13

10

12

C2
47n

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

T

9

R1
18k2

GM3008

5

10

REGULATOR

-

A

8

R2
105k

4

GP537

-

B

7

6

R3
20k

R4 15k

C3 47n

7

17

18

390k

9

V.C.

Fig. 2 Typical Hearing Instrument Application

1.3VDC

GS551

5

-

C

2

4

-

D

REFERENCE

VOLTAGE

9

R5
60k

8

6

5

1

6

1

4

E

7

3

8

3

10

REC

2

CI2960

C4
47n

C5
47n

3

520 - 70 - 05