Quectel EG91 Series Hardware Design page 77

 Do not place components on the opposite side of the PCB area where the module is mounted, in order
to facilitate adding of heatsink when necessary.
 Do not apply solder mask on the opposite side of the PCB area where the module is mounted, so as
to ensure better heat dissipation performance.
 The reference ground of the area where the module is mounted should be complete, and add ground
vias as many as possible for better heat dissipation.
 Make sure the ground pads of the module and PCB are fully connected.
According to customers' application demands, the heatsink can be mounted on the top of the module,

or the opposite side of the PCB area where the module is mounted, or both of them.
 The heatsink should be designed with as many fins as possible to increase heat dissipation area.
Meanwhile, a thermal pad with high thermal conductivity should be used between the heatsink and
module/PCB.
The following shows two kinds of heatsink designs for reference and customers can choose one or both
of them according to their application structure.
EG91 Module
Application Board
Figure 39: Referenced Heatsink Design (Heatsink at the Top of the Module)
EG91_Hardware_Design
Heatsink
Thermal Pad
Shielding Cover
LTE Standard Module Series
EG91 Hardware Design
Heatsink
Application Board
76 / 93