Data Sheet

W M B T 0 1 ( - s , - s c ) D a t a s h e e t
20
/
36
3.2.2 Even only part of PINs are used, it is recommended to do full pad design,
symmetric pad design, or asymmetric pad design (refer to Figure 3-1). During reflow, if
the pad paste melts, the module is vulnerable to non-balanced force pull. It may lead
to PIN short circuit if the module deflects under the action of torque.
Figure 3-1: Asymmetric Pad Design
3.3.3 Layout Requirements
a. For PCB double sided layout, it is recommended to process on 2nd side.
b. The layout of other elements should be avoided on the outermost end 1mm
area of module pad. In order to increase repair space, other elements layouts should
be as far away from the module as possible. The minimum distance between the
module pad and PCB board edge is 1.5mm.
3.3.4 Compatible Design Considerations
To prevent any hidden risks, module placement area (See the red rectangle in
Figure 3-2 below) shouldn’t include any pad design which intends to be compatible
with other elements.
Figure 3-2: Module Placement Area Example
4. SMT Notes