TDA5255E1 Datasheet, PDF (45/93 Pages) Infineon Technologies AG – ASK/FSK 434MHz Wireless Transceiver

Confidential
TDA5255 E1
Version 1.1
Application
Sparam_measured_434.pcx
Figure 3-9 Sparam_measured_200M
Above you can see the measurement of the evalboard with a span of 200MHz. The evalboard has
been optimized for 3V. The load is about 250+j0 at 434,2MHz.
A tuning-free realization requires a careful design of the components within the matching network.
A simple linear CAE-tool will help to see the influence of tolerances of matching components.
Suppression of spurious harmonics may require some additional filtering within the antenna
matching circuit. Both can be seen in Figure 3-10 and Figure 3-11 The total spectrum of the
evalboard can be summarized as:
Carrier fc
fc-18.1MHz
fc+18.1MHz
2^nd harmonic
3^rd harmonic
+9dBm
-71dBm
-71dBm
-45dBm
-48dBm
Preliminary Specification
45
2002-11-28