Baseband Signal Processor
FX829
1.4
External Components
C1
C2
C3
C4
C5
C6
C7
C8
C9
22pF
22pF
68pF
0.1µF
0.1µF
100pF
0.1µF
Note 2
5.6nF
±20%
±20%
±20%
±20%
±10%
±20%
±20%
±20%
±20%
R1
R2
R3
R4
R5
R6
R7
1M
W
Note 1
Note 1
100k
W
100k
W
Note 2
22k
W
±5%
±10%
±10%
±10%
±10%
±10%
±10%
X1
4.032MHz
±100ppm
Notes:
1. R2, R3, R4 and C3 form the gain components for the Summing Amplifier (AMP2).
R2 and R3 should be chosen as required from the system specification, using the
following formulae:
Audio Gain =
−
DTMF Gain =
−
R4
R3
R4
R2
2. R5, R6, C6 and C8 form the gain components for the Rx Input Amplifier (AMP1).
R6 should be chosen as required by the signal level, using the following formula:
Gain
=
−
R5
R6
C8 x R6 should be chosen so as not to compromise the low frequency performance of
this product.
Figure 2 Recommended External Components
©
1997 Consumer Microcircuits Limited
7
D/829/4
CMLMICRO [ CML MICROCIRCUITS ]
