LPM2100 mg NB Module Hardware User Guide
Shanghai Yuge Information Technology Co., Ltd.
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Figure 4-1 Main antenna matching circuit diagram
The 26-pin of the LPM2100 mg series module is a Bluetooth antenna interface. To
facilitate antenna debugging, a
π
-type matching circuit needs to be added to the
motherboard, and the 50-ohm impedance line is taken. The recommended circuit is as
follows
：
Figure 4-2 Bluetooth antenna matching circuit diagram
LPM2100 mg series module two antennas are 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.
。
