Gennum Corporation LD511 Datasheet

Class A

Compression Amplifier

LD511 DATA SHEET

FEATURES

• 64 dB typical electrical gain

• 0.94 V

DC voltage regulator

• 7 ms attack time, 40 ms release time

• 15 dB threshold adjustment

• low noise and distortion

• compression ratio

∞ : 1

• 0.3 kHz - 6 kHz frequency response

STANDARD PACKAGING

• 10 pin MICROpac

• 10 pin MINIpac

• 10 pin PLID

®

• 10 pin SLT

• Chip (59 x 59 mils)
Au Bump

DESCRIPTION

The LD511 is a Class A compression amplifier which can
operate over a range of DC battery voltages from 1.1 V
to 2.4 V. A voltage regulator, which is independent of supply
voltage variations, is on-chip to supply a stable 0.94 V

DC bias

to the amplifier circuitry and to the microphone.

The LD511, in compression, has approximately 15 dB of
threshold adjustment by varying

R

(see application circuit)

TH

and a compression function ratio of ∞ : 1.

Minimum attack and release times are fixed at 7 ms and 40 ms
respectively and they can be adjusted simultaneously by
changing the filter capacitor on pin 8, although the ratio of
attack to release time is kept constant.

The output stage bias can be set to accommodate different
receiver impedances by changing the value of
voltage across

R

(pin 2 to ground) is a constant 27 mV so the

E

bias current is 27 mV divided by the total value of

R

E

R

in parallel

E

. The

with 500 Ω.

V

REG

A IN

Revision Date: January 2001

A OUT B IN V

10

VOLTAGE

REGULATOR

7

9

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

- A

R

IN

8

C

AGC

BLOCK DIAGRAM

1

10K 35K

RECTIFIER

- B

GND

B

6

20K

3

B OUT

R

E

5

AGC

24

R

E

500 - 32 - 11

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

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

ABSOLUTE MAXIMUM RATINGS

PARAMETER VALUE/UNITS

Supply Voltage 2.4 V DC

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

CAUTION

CLASS 1 ESD SENSITIVITY

AGC

GND

B OUT

R

B IN

PIN CONNECTION

5

E

6

V

B

V

REG

C

AGC

A IN

101

A OUT

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

= 1.3 VDC

B

PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS

COMPRESSION INACTIVE (S1 OPEN)

Gain A

V

60 64 68 dB

Input Referred Noise IRN NFB 0.2 - 10kHz at 12 dB/oct - 2.0 4.0 µV
Total Harmonic Distortion THD - 1 3 %
Amplifier Current I
Transducer Current I
Input Impedance R
Regulated Voltage V
On Chip Emitter Resistance R
Emitter Bias Voltage (pin 2) V

AMP

TRANS

IN

REG

E

RE

- 0.4 0.6 mA

1.35 1.6 2.0 mA

-15 -kΩ

0.90 0.96 1.0 VDC

- 500 - Ω

-27 -mV

COMPRESSION ACTIVE (S1 CLOSED)

Compression Range - ∞ -dB
Total Harmonic Distortion THD
Attack Time T
Release Time T
Compression Output V
Compression Output Change ∆V

COMP

ATT

REL

COMPOUT

COMPOUTV2

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

Notes: 1. ∆V

COMPOUT

R
50

= V

56K

S

OUT[V2

V2

=120mV] - V

3.9K

27K

56

V2 = 1 mV - 4.0 7.0 %
V2 switched from 112µV to 2 mV - 7 - ms

-40 -ms

V2 = 1 mV - 0.10 0.18 VRMS

= 120 mV; Note 1 - 13 20 mVRMS

COMPOUT

C

S

0.047

7

9

VOLTAGE

REGULATOR

- A

84

0.033

10K 35K

RECTIFIER

I

AMP

110

- B

6

0.068

20K

3

R

E

5

2

0.0047

S1

R

B

4.7

I

TRANS

Hammond

99966

VB=1.3 VDC

V

OUT

R

L

600

500 - 32 - 11

10

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

2.2

Fig. 1 Test Circuit

2

15