Datasheet

Revision 1.5 Page 36 of 41
nRF905 Product Specification
15.2 PCB Layout Example; Differential Connection to a Loop Antenna
Figure 13. shows a PCB layout example for the application schematic in Figure 12. A double sided FR-4
board of 1.6mm thickness is used. This PCB has a ground plane on the bottom layer. Additionally, there
are ground areas on the component side of the board to ensure sufficient grounding of critical components.
A large number of via holes connect the top layer ground areas to the bottom layer ground plane. There is
no ground plane beneath the antenna.
Figure 13. PCB layout example for nRF905, differential connection to a loop antenna
A fully qualified RF layout for the nRF905 and its surrounding components, including antennas and match-
ing networks, can be downloaded from www.nordicsemi.no
.
a) Top silk screen
No components in bottom layer
b) Bottom silk screen
c) Top view
d) Bottom view