TELEFUNKEN Semiconductors

U4313B

Rev. A1: 23.06.1995

11 (14)

16

15

14

13

12

3

4

12

11

10

56

7

9

8

Wake up

out

8.2 k

W

30 k

W

10 nF

1.5 nF

100 k

W

100 k

W

100 nF

100 nF

22 pF

56

W

300

W

100 k

W

10 nF

100 k

W 220 nF

220 nF

R13

100 k

W

10 k

W

220 nF

220 k

W

Wake up

22 k

W

Data filter

output

10 k

W

Comparator

output

IF input

Filter

22 k

W

22 k

W

100 nF

10

mF

10

mF

TOKO A119ACS-19000Z

(L = 2.2

mH, C = 100 pF)

Figure 26. FM test circuit with 2 kHz Bessel low pass data filter

–70

–60

–50

–40

–30

–20

–10

0

10

0

2040

6080

100

IF-input level ( d

mBV )

95 10291

S + N

N

Figure 27. Signal to noise ratio FM; deviation 22.5 kHz

0

0.5

1.0

1.5

2.0

2.5

10.3

10.5

10.7

10.9

11.1

Frequency ( MHz )

95 10290

Figure 28. FM-discriminator characteristic