0433BM15A0001E Datasheet, PDF (8/27 Pages) Johanson Technology Inc. – Johanson Technology Matched Balun Filters for CC110x & CC111x

Design Note DN025
Figure 8. Alternative Grounding on Layer 1
The routing in Figure 8 is the same as Figure 7 apart from the ground fill around the balun.
Figure 9. Layer 2 of CC1101 JTI 868/915 MHz Reference Design Layout
On the second layer; it is important to have a solid ground plane underneath the RF structure
and to avoid any routing directly underneath the RF. The power routing has been routed in a
star formation and the power tracks must always be routed to the decoupling capacitor first;
then from the decoupling capacitor to the pad of the CC1101.
SWRA250A
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