APPLICATION NOTE

TEA7092 - TELEPHONE SET INTEGRATED CIRCUIT

AN848/1096

CONTENTS

Pages

I.

TEA7092 GENERAL INFORMATION . . . .... . . . . . . . . . . . .... .. . . . . . . . ... . . . .

3

I.1.

SETTING THE TEA7092 APPLICATION . . . . . . . . . . . . . . . . . .... .. .. .. . . . . . . ...

3

I.2.

PINOUT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .... ... .. . . .. ... ... ... .... ...

4

I.3.

BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . .... ... .. . . .. ... ... ... .... ...

5

I.4.

INPUT/OUPUT CONFIGURATIONS . . . . . . . . . . . . . .... ... ... . ... . . . . . . . . ....

6

II.

SPEECH FEATURE . . . . .... ... .. . . . . . . . . . . . ... .. . . . . . . . ... ... ... .... .. .

14

II.1.

DC CHARACTERISTICS . . . . . . . . . . ... ... ... .... ... ... ... ... ... ... .... ...

14

II.1.1.

TEA7092 DC Voltage . . . . . . . . . . . . . ... ... ... .... ... ... ... ... ... ... .... ...

14

II.1.2.

Telephone Set DC Voltage . . .... .. . . . . . . . . . . . ... ... .. . . . . ... ... ... .... ...

14

II.1.3.

Start Up Characteristics . . . . . . . . . . . ... ... ... .... ... ... ... ... ... ... .... ...

15

II.1.4.

17

II.2.

IMPEDANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... ... ... .... .. .

18

II.3.

TRANSMIT CHANNEL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .... .. .. .. . . . . . . ...

19

II.3.1.

General Information - Maximum Gain Adjustment . . . . . . . . . . . . . . . . . . . . . . .... ...

19

II.3.2.

Softclipping Threshold (Maximum Line Level). . . . . . . . . . . . . . . . . ... ... ... .... ...

20

II.3.3.

Line Loss Compensation A.G.C. Adjustment . . . . .... ... ... ... ... ... ... .... ...

21

II.3.4.

A.G.C. Inhibition . . . . . . . . . . . . . . . . . ... ... ... .... ... ... ... ... ... ... .... ...

21

II.3.5.

Transmit Squelch / Antiacoustic Feedback Stage . . . . .... ... ... . ... . . . . . . . . ....

22

II.4.

SIDETONE . . . . . . . . . . . . . . . . . . . . . ... ... ... .... ... ... ... ... ... .... . . . ...

23

II.4.1.

General Information . .... ... ... .. . ... ... ... .... ... ... ... ... ... .... . . . ...

23

II.4.2.

One Sidetone Network Principle . . . . . . . . . . . . . . . . . . . . . . . . . . . ... ... ... .... .. .

24

II.4.3.

Line Tracking Sidetone Network Principle. . . . . . . . . . . . . . . . . . . . ... ... ... ... . . . .

24

II.4.4.

Sidetone Programming for PABX Application .... . . . . . . . ... ... .. . . . . . . . . . . . . . .

25

II.5.

RECEIVE CHANNEL . . . . . . . . . . . . . ... ... ... .... ... ... ... ... ... ... .... ...

26

II.5.1.

General Information - Maximum Gain Adjustment . . . . . . . . . . . . . . . . . . . . . . .... ...

26

II.5.2.

Maximum Output Level . . . . . .... .. . . . . . . . . . . . ... .. . . . . . . . ... ... ... .... .. .

27

II.5.3.

Line Loss Compensation / A.G.C. Adjustment . . . . . . . . . . . . . . . . ... ... ... ... . . . .

30

II.5.4.

A.G.C. Inhibition . . . . . . . . . . . . . . . . . ... ... ... .... ... ... ... ... ... ... .... ...

30

II.5.5.

+6dB Mode . .... .... ... .. . . . . . . . ... ... ... .... ... ... ... ... ... ... .... ...

30

II.6.

HANDSFREE INTERFACE. . . . . . . . . . . . . . . . . . .... ... ... ... ... ... ... .... ...

30

III.

CALL PROGRESS MONITOR AND GROUP LISTENING MODES . .... ... .... ...

31

III.1.

GENERAL INFORMATION. . . . . . . . .... ... ... .... ... ... ... ... ... . . . . . . . ...

31

III.2.

LOUDSPEAKING PART SUPPLY . . .... ... ... .... ... ... ... ... .... . . . . . . ...

32

III.3.

SOFTCLIPPING STAGE. . . . . . . . . . . ... ... ... .... ... ... ... ... ... ... .... ...

33

III.4.

ANTIACOUSTIC FEEDBACK FEATURES . . . . . . .... ... ... ... ... ... ... .... ...

33

III.5.

MAXIMUM OUTPUT POWER. . . . . . . . . . . . . . . . . . . . . . .... ... ... ... . . . ... ... .

35

III.6.

EXTERNAL POWER SUPPLY FACILITY. . . . . . . .... ... ... ... ... ... ... .... ...

36

III.7.

RING MELODY CONTROL MODE. . . . . . . . . . . . .... ... ... ... ... ... ... .... ...

37

III.8.

BEEP ERROR GENERATOR . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... ... ... .... .. .

38

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