Hardware Development Guide of Module Product
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MF206A
5.
During the layout and wiring of peripheral circuits, for the wiring of power and signal cables, keep a
distance of 2 times of the line width, so as to effectively reduce the coupling between signals and keep a
clean reflux path for the signal.
6.
During the design of peripheral power circuits, the de-coupled capacitor should be placed closed to the
module power PIN, the high-frequency high-speed circuit and the sensitive circuit should be placed far
away from the border of PCB. They should better be separated during layout, so as to reduce the
interference between them and protect the sensitive signal.
7.
For the circuit or device on the side of system board that might interfere with the module, it should be
shielded during design.
5.6.2
ESD Design Requirements
MF206A is embedded on the side of system board, so the user needs to make the ESD protection during design.
For the key input/output signal interface, such as the (U)SIM card signal interface, the ESD device should be
placed closely for protection. Besides, on the side of main board, the user should reasonably design the structure
and PCB layout, guarantee that the metallic shielding shell is fully grounded, so as to leave a smooth discharge
channel for ESD.
5.7
Antenna Indexes
The module supports the AGPS/GPS function, so the system equipment needs to add the GPS antenna. The
design of GPS antenna is consistent with that of the main antenna, and its efficiency index can be 3dB lower.
The separation degree between the main antenna and the diversity antenna is required to be greater than 12dB.
The antenna index is divided into the Inactive index and Active index. The Inactive index includes S11,
efficiency, gains, orientation diagram and polarity, which can be used as the parameter measuring the
performance of the antenna itself. The Active index is also called the OTA index, including TRP (all-round
radiation power), TIS (all-round receiving sensitivity), radiation orientation diagram, which is an important
index measuring the radiation performance of the whole set (including the antenna, module, main board).