LPM2100 bg NB Module Hardware Usage Guide
Shanghai Yuge Information Technology Co., Ltd.
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Figure 4-1 Main antenna matching circuit diagram
LPM2100 bg series module RF antenna is extracted by pad method.
①
The antenna impedance trace needs to be away from the digital signal line, power
supply and other interference signals.
②
The antenna impedance traces need to be three-dimensionally packaged, and more
holes are added on both sides of the trace to isolate.
③
The antenna line loss is less than 0.3dB, so keep the PCB trace as short as possible.
④
The parasitic capacitance of the TVS tube pin itself in antenna matching must be
small to avoid signal interference. Parasitic capacitance must be less than 0.5pF or even lower.
4.3 RF signal line routing guide
For the user, the characteristic impedance of all RF signal lines should be controlled at
50
Ω
. The impedance of the RF signal line is determined by the dielectric constant of the
material, the trace width (W), the ground clearance (S), and the height of the reference ground
plane (H). Please use the impedance simulation tool to calculate the impedance value of the
RF trace. The control of the PCB characteristic impedance is usually in the form of microstrip
lines and coplanar waveguides.
Figure 4-2 Complete structure of the microstrip line
