CMX909BP4 参数 Datasheet PDF下载

GMSK Packet Data Modem

CMX909B

1.4

External Components

Figure 2 Recommended External Components

R1

R2

R3

R4

See section 1.5.1.10

100k ohm

1M ohm *

See section 1.5.1.12

C1

C2

C3

C4

0.1 µF

0.1 µF

See section 1.5.4.3 *

See section 1.5.4.3 *

C5

C6

C7

X1

See section 1.5.1.12

See note below

See note below

See section 1.5.4.3 *

* Refer also to 1.5.1.14

Tolerances:

R4 ±5%

R2, C5 ±10%

all other components ±20%

C6 and C7 values should satisfy the following: C (in Farads) x data rate (bits/second) = 120 x 10-6

e.g.

Data Rate

(kbits/sec)

4.0

4.8

8.0

9.6

16.0

19.2

32.0

38.4

C6/C7 (nF)

30

22

15

12

6.8

6.8

3.9

3.3

©

2001 Consumer Microcircuits Limited

6

D/909B/1