7

GTR

1

23

4

5

6

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

I

LS

47 F

1N4148

V

CC

IVLS

MIC1

MIC2

EAR-

EAR+

GREC

470nF

2k

Ω

2.2 F

300

Ω

15k

Ω

10k

Ω

1.3k

Ω

V

REF

10 F

24V

47

Ω

47nF

100 F

V

RING

BUZ

V

MC

V

REF

DTMF

V

RMC

SOFT

AGC

10 F

100nF

10 F

560k

Ω

100nF

V

CC

TE A7088A

3.9k

Ω

V

REF

47 F

620

Ω

13V

1 F

82k

Ω

33

Ω

C2

4.7nF

1.6k

Ω

100nF

600

Ω

100 F

I

L

15k

Ω

S ide tone

V

CC

Vm

Gtl/Gts = 20 log

V

12

V

m

Mmic = 20 log

V

V

Eff = 20 log

V

ear

V

m

V

ear

Figure 13 : Test 3 (Gtl / Gts / Zmic / Nt / Mmic / Dt / Vlmax / Eff)

7

GTR

1

23

4

5

6

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

I

LS

47 F

1N4148

V

CC

IVLS

MIC1

MIC2

EAR-

EAR+

GREC

470nF

2k

Ω

2.2 F

300

Ω

15k

Ω

10k

Ω

1.3k

Ω

V

REF

10 F

47

Ω

47nF

100 F

V

RING

BUZ

V

MC

V

REF

DTMF

V

RMC

SOFT

AGC

10 F

100nF

10 F

560k

Ω

100nF

V

CC

TEA7088A

3.9k

Ω

V

REF

47 F

620

Ω

13V

1 F

82k

Ω

33

Ω

C2

4.7nF

1.6k

Ω

100nF

100 F

I

L

15k

Ω

Sidetone

V

CC

I

AC

V

AC

Grl/Grs = 20 log

24V

V

ear

V

ear

V

12

Figure 14 : Test 4 (Grl / Grs / Dr / Mear / Nr)

TEA7088A

13/17