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 *
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 *
See section 1.5.1.12
* Refer also to 1.5.1.14
Tolerances: R4 ±5%
R2, C5 ±10%
all other components ±20%
-6
C6 and C7 values should satisfy the following: C (in Farads) x data rate (bits/second) = 120 x 10
e.g.
Data Rate
(kbits/sec)
4.0
C6/C7 (nF)
30
4.8
22
8.0
15
9.6
12
16.0
19.2
32.0
38.4
6.8
6.8
3.9
3.3
ã 2001 Consumer Microcircuits Limited
6
D/909B/1
CMLMICRO [ CML MICROCIRCUITS ]
