N1_Hardware_User_Guide
Copyright © Neoway Technology Co., Ltd
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Figure 7-8
Power supply reference for active antenna
LNA
Active
Antenna
N1
LDO
PWR_input
22uF
33pF
100nH
33pF
50
Ω
impedance line
Add decoupling capacitors if using the active antenna because no decoupling capacitor is designed for
116th pin (GPS_ANT) inside the module.
Do not use active GPS antenna with great gain. Otherwise, the GPS cannot work properly because of
fullsignals.
7.3.3 Passive GPS Antenna Design Reference
If developersadopt a multiple-layer PCB and are experienced in RF design, use a passive ceramic chip
antenna or other types of GPS antenna design. This method might reduce the BOM cost but require high
skills to produce a reliable working board. Figure 7-9 shows a reference design of the passive GPS circuit
(the 33 pF capacitor can be omitted).
