User's Manual

Wi-Fi&Bluetooth Module Series
FC41D_Hardware_Design
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ANT_WIFI/BT
R1
C2
NM
C3
NM
FC41D
0R
C1
NM
L1
NM
Figure 11: RF Antenna Reference Design
When using the PCB antenna on the module, the module should be placed at the side of the motherboard
as far as possible, and the distance of keeout between PCB antenna to GND of motherboard should be at
least 3mm, and the distance between PCB antenna to connectors, pin headers, ethernet port and any
other high components on the motherboard should be at least 16 mm. All layers in the PCB of the
motherboard under the PCB antenna should be designed as keepout areas.
Figure 12: keepout areas on the motherboard
3.13.6. Reference Design of RF Layout
The characteristic impedance of all RF traces on your PCB should be controlled at 50 Ω. The impedance