User's Manual

Bluetooth Low Energy Module
Shanghai Ehong Technologies Co., Ltd
8. Layout and Soldering Considerations
8.1. Soldering Recommendations
EH-MC20 is compatible with industrial standard reflow profile for Pb-free solders. The
reflow profile used is dependent on the thermal mass of the entire populated PCB, heat
transfer efficiency of the oven and particular type of solder paste used. Consult the
datasheet of particular solder paste for profile configurations.
Comply will give following recommendations for soldering the module to ensure reliable
solder joint and operation of the module after soldering. Since the profile used is
process and layout dependent, the optimum profile should be studied case by case.
Thus following recommendation should be taken as a starting point guide.
 Refer to technical documentations of particular solder paste for profile
configurations
 Avoid using more than one flow.
 Reliability of the solder joint and self-alignment of the component are dependent on
the solder volume. Minimum of 150um stencil thickness is recommended.
 Aperture size of the stencil should be 1:1 with the pad size.
 A low residue, “no clean” solder paste should be used due to low mounted height of
the component.
8.2. Layout Guidelines
For optimal performance of the antenna place the module at the corner of the PCB as shown in the figure
3. Do not place any metal (traces, components, battery etc.) within the clearance area of the antenna.
Connect all the GND pins directly to a solid GND plane. Place the GND vias as close to the GND pins as
possible. Use good layout practices to avoid any excessive noise coupling to signal lines or supply
voltage lines. Avoid placing plastic or any other dielectric material closer than 6 mm from the antenna.
Any dielectric closer than 6 mm from the antenna will detune the antenna to lower frequencies.