Yehuda,
At a previous employer we were placing BGA's on PCMCIA cards of the same
thickness, and also had fine-pitch on the backside. I am going to assume you are
up to speed with BGA req'mnts (Bake that moisture out!)...we also baked our
boards before use (very thin, multi-layer).
Solid support of the board and panel is very important during paste print,
placement and reflow. We used carrier pallets. I fab'ed these (using our board
router) from a high-temp pcboard mat'l, so it could withstand multiple relows. I
used locating pins in the pallets, and tiny bits of dbl-sided tape in strategic
locations to help with bd hold-down. Sounds hokey, but gosh-durnit, it worked!
We had a fairly dense backside, but pin support underneath during paste print is
also important. We had a 3-up panel, and we had to put hold-down tabs on each
board to keep it from vibrating during routing. and since traces were very close
to the bd edge, I used tapered pins for precise panel/bd alignment. Good Luck.
United Technology Electronic Controls
Jeff L. Hempton, Sr. SMD Engineer
______________________________ Forward Header __________________________________
Subject: [TN] Fw: ASSY: PBGA on PCMCIA card
Author: Orna and Yehuda <[log in to unmask]> at Internet
Date: 9/17/98 12:19 PM
Hi,
I am reposting this message, maybe someone will be able to point me in the right
direction.
Best regards,
Yehuda
-----Original Message-----
From: Orna and Yehuda <[log in to unmask]>
To: IPC TechNet <[log in to unmask]>
Date: Monday, August 31, 1998 11:09 AM
Subject: ASSY: PBGA on PCMCIA card
Hi Technetters,
A friend of mine who deals with assembly asked me to pose the following
question:
Can anyone advise, what considerations should I take, in order to assemble PBGA
components (about 300 pinouts) on a PCMCIA board - 0.5 mm thickness.
Please point out if there are any special steps in the process and what
reliability tests should the finished product pass.
Best regards,
Yehuda
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<DIV><FONT color=#000000 size=2>Hi,</FONT></DIV>
<DIV><FONT color=#000000 size=2></FONT><FONT size=2>I am reposting this message,
maybe someone will be able to point me in the right direction.</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Best regards,</FONT></DIV>
<DIV><FONT size=2>Yehuda</FONT> </DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2><B>-----Original Message-----</B><BR><B>From:
</B>Orna and Yehuda <<A
href="mailto:[log in to unmask]">[log in to unmask]</A>><BR><B>To
:
</B>IPC TechNet <<A
href="mailto:[log in to unmask]">[log in to unmask]</A>><BR><B>Date: </B>Monday,
August 31, 1998 11:09 AM<BR><B>Subject: </B>ASSY: PBGA on PCMCIA
card<BR><BR></DIV></FONT>
<DIV><FONT color=#000000 size=2>Hi Technetters,</FONT></DIV>
<DIV><FONT color=#000000 size=2>A friend of mine who deals with assembly asked
me to pose the following question:</FONT></DIV>
<DIV><FONT color=#000000 size=2><FONT size=4>
<P align=left><FONT size=2>Can anyone advise, what considerations should I take,
in order to assemble PBGA components (about 300 pinouts) on a PCMCIA board - 0.5
mm thickness. </FONT></P>
<P><FONT size=2>Please point out if there are any special steps in the process
and what reliability tests should the finished product pass. </FONT></P>
<P><FONT size=2></FONT> </P>
<P><FONT size=2>Best regards,</FONT></P>
<P><FONT size=2>Yehuda</FONT></P></FONT></FONT></DIV></BODY></HTML>
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