User's Manual

GS780MIZ Module Data Sheet
NOTES:
1. Perform adequate test in advance as the reflow temperature profile varies according to the
conditions of the parts and boards, and the specifications of the reflow furnace.
2. Max number of reflow supported is two.
3. Temperature uniformity inside the IR reflow oven must be tightly controlled and multiple
thermocouples should be used. The locations should also include multiple points INSIDE the
module RF shield. The temperature profile of all thermocouples must meet the requirements
of the above table.
4. Pay close attention to “Melting Time over 220oC”. Sufficient time is needed to completely
melt all solder.
5. Be careful about rapid temperature rise in preheat zone because it can cause excessive
slumping of the solder paste.
6. If the preheat is insufficient, large solder balls tend to be generated. Conversely, if
performed excessively, fine balls and large balls will generate in clusters at a time.
7. If the temperature is too low, non-melting tends to be caused in the area with large heat
capacity after reflow.
8. Be careful about sudden rise in temperature because it may increase the slump of solder
paste.
9. Be careful about slow cooling because it can cause the positional shift of parts and a decline
in joining at times.
10. A no clean flux should be used during the SMT process.
GS780M-DS-00001 Page 17 Preliminary
Release 1.03 Confidential May 26, 2016