CLM920_AC3 Module Hardware Usage Guide
Shanghai Yuge Information Technology co., LTD
- 39 -
tube at the D1/D2 of the antenna connection.
The parasitic capacitance of the TVS tube pins themselves must be small to avoid signal
interference. The ESD protection component used on the antenna must take into account
the frequency band used by the antenna and the minimum parasitic capacitance that can
be accepted by different frequency bands. The ESD protection component usually used
on the antenna must have a parasitic capacitance value of less than 0.5pF or even more.
low.
Antenna impedance traces need to be away from digital signal lines, power supplies and
other interference signals.
The antenna impedance traces need to be three-dimensionally packaged, and the ground
holes are added on both sides of the trace to isolate.
3.14.2 RF trace reference
The main set and diversity antenna of the CLM920 AC3 module are extracted by pad. The
antenna pad to the antenna feed point must use microstrip lines or other types of RF traces.
The characteristic impedance of the signal line should be controlled at 50
Ω
.
The impedance of the RF RF signal line is determined by the material's dielectric constant,
trace width (W), ground clearance (S), and reference ground plane height (H). Therefore, the
RF trace requires an impedance simulation tool to calculate the impedance of the RF trace.
Figure 3-25 Complete structure of the microstrip line
