Silicon Laboratories Si435 Series, Руководство по проектированию оформления

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A N 6 8 5
18 Rev. 0.4
Figure 19. Layout Structure of 4012-PSC10B434 (4012CPSC10B434) Pico Board
6.1. Layout Design Guidelines for the Si4012 RF IC
The layout design principles for the Si4012 RF IC, are the same as the Si435x and Si4455 RF ICs with the
following additional specific issues:
 The separated inductors between the differential output pins (LM2, LM4) should be placed as close as
possible to the TX pins of the RF IC in order to reduce the series parasitic inductance which may cause de-
tuning effects in the matching network
 The length of the leading traces for the two separated inductors (LM2, LM4) should be equal to each other
 The choke inductor (LM1) and the capacitor for suppressing the 2nd harmonic (CM3) should be placed to
the bottom layer and connected into the common symmetric point of the separated inductors
6.2. PCB Antennas for the Si4012 RF IC
The Si4012 RF IC can use the same PCB BIFA antennas with 50

single ended inputs as those that are applied
to the Si4455/435x RF ICs.Refer to section 5 and application note, "AN686: Antennas for the Si4455/4355 RF ICs"
for further details. The manufacturing pack including CAD and CAM files can be found on the
www.silabs.com
home page.