User's Manual

GSM/GPRS/GNSS Module Series
MC20 Hardware Design
MC20_Hardware_Design Confidential / Released 85 / 95
7 Storage and Manufacturing
7.1. Storage
MC20 module is stored in a vacuum-sealed bag. The storage restrictions are shown as below.
1. Shelf life in the vacuum-sealed bag: 12 months at <40ºC and <90%RH.
2. After the vacuum-sealed bag is opened, devices that need to be mounted directly must be:
 Mounted within 72 hours at the factory environment of ≤30ºC and <60% RH.
 Stored at <10% RH.
3. Devices require baking before mounting, if any circumstance below occurs.
 When the ambient temperature is 23ºC±5ºC and the humidity indication card shows the humidity
is >10% before opening the vacuum-sealed bag.
 Device mounting cannot be finished within 72 hours when the ambient temperature is <30ºC and the
humidity is <60%.
 Stored at >10% RH.
4. If baking is required, devices should be baked for 48 hours at 125ºC±5ºC.
As the plastic package cannot be subjected to high temperature, it should be removed from devices
before high temperature (125ºC) baking. If shorter baking time is desired, please refer to
IPC/JEDECJ-STD-033 for baking procedure.
7.2. Soldering
Push the squeegee to apply the solder paste on the surface of stencil, thus making the paste fill the
stencil openings and then penetrate to the PCB. The force on the squeegee should be adjusted properly
so as to produce a clean stencil surface on a single pass. To ensure the module soldering quality, the
NOTE