U4083B

Preliminary Information

TELEFUNKEN Semiconductors

Rev. A2, 07-Apr-97

1 (11)

Low-Power Audio Amplifier for Telephone Applications

Description

The integrated circuit, U4083B, is a low power audio

amplifier for a telephone loudspeaker. It has differential

speaker outputs to maximize the output swing at low

supply voltages. There is no need for coupler capacitors.

The U4083B has an open loop gain of 80 dB whereas the

closed loop gain is adjusted with two external resistors. A

chip disable pin permits powering down and/or muting

the input signal.

Features

D Wide operating voltage range: 2 to 16 V

D Battery powered application due to low quiescent

supply current: 2.7 mA typical

D Chip disable input to power down the integrated

circuit

D Low power down quiescent current

D Drives a wide range of speaker loads

D Low harmonic distortion (0.5% typical)

D Wide range gain adjustable: 0 dB to 46 dB

Benefits

D Low number of external components

D Low current consumption

Block Diagram / Application Circuit

0.1 F

–

+

–

+

4 k

4 k

125 k

50 k

50 k

Amp.1

Amp.2

Bias

circuit

V

S

6

5

8

VO1

VO2

1

CD

GND

7

4

Vi

3

2

Rf

75 k

Ri

3 k

C

i

Input

C2

5 F

C1

1 F

93 7781 e

W

W

W

W

W

W

W

m

m

m

FC1

FC2

Figure 1.

Order Information

Extended Type Number

Package

Remarks

U4083B-AFP

SO8

U4083B-AFPG3

SO8

Taped and reeled