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8.Alignment
1).
Turn on the laser, make sure the laser is pointed to the center of the pad for the BGA, put the BGA chip
on the PCB board
2).
Select the proper profile, choose the mouting model Then click
3).
The upper sucker will goes down to
welding position as settled in picture 6 to pick up the
BGA chip, and goes up the Optic position settled in picture 6
,
4).
Pull the optical lens out, the BGA tin ball and welding pad will be displayed on the screen You can
check images of tin balls on the screen through the adjusting angle handle.X axis.Y axis The tin ball and
PCB welding position must be coincide completely on the screen
5).
Push the CCD carmera back, the screen will appear like this. Click yes to soldering the chip
9. Soldering
1
. Switch on the power, select the proper stored temp profile or set for yourself if needed.
2
. Switch on the laser, put the BGA soldering pad center to the laser. Fasten the supporter. Install the
proper nozzle, 2mm-3mm larger than the BGA.
3.install the right nozzle 2mm larger than the BGA chip,
click
.heating as your
chosen data Cool the BGA chip after the procedure finished Raise the upper heater to make the bottom
of upper heater has 3-5mm distance from the upper surface of BGA chip, and keep cooling for 30-40
seconds Or you can move away the warm heater after the starting light off Then take away the PCB
board from the supporter
(1) Null welding:
Because of counterpoint by hand will cause deviation between chip and welding plate, surface tension of
tin ball will have a process of automatic correction between BGA chip and welding pad Once heating,
BGA falls not evenly, which will cause that the chip drops not evenly It will cause the phenomenon of
missing weld and false weld if stop reflowing at this time, the chip will not fall normally So it is necessary
for you to extend heating time of third .forth temperature zones or add the bottom pre-heating
temperature to make the tin balls meltdown and drop evenly
(2) short-circuiting
：
When the ball reached the melting point, it is in a liquid state , if too long or too high temperature and
pressure, it will destroy surface tension of solder balls and the supporting role, resulting in short-circuit
phenomenon when reflows, the chips fall entirely on the PCB pads the , so we need to appropriately
Содержание DH-G200
Страница 5: ...5 Functions...
Страница 9: ...9 3 Click the input box it will appear as follow...
