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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi Horst,</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>if the board is manufactured properly (layer adhesion
is according to standards) there is the risk of delamination if there is too
much humidity incorporated in the board. This happens depending on relative
humidity and time of storage before soldering.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>It is always a recommended procedure to bake the
board at 120-130°C for about 3 hours before assembling and soldering. Futhermore
you should do the same procedure with bga and other big chips because they
could have a base board of the same material and the same risk of delamination
or popcorn during the soldering process.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>You should also be sure about the real (measured)
temperture profile on your board during the reflow process. It also depends on
the amount of parts assembled on the board and you have only assembled a few
parts which could result in a higher temperature.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>If you have additional questions I will send you my
tel.no. directly.</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span lang=EN-GB style='font-size:
10.0pt;font-family:Arial'>73 Gerd, DJ8AY</span></font></p>
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12.0pt'> </span></font></p>
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