Amol,
I don't know the surface tension of solder off hand, but I would think
that for a small QFN, the volume of solder would be a better place to
start. Figure out how high you want the part to sit, and then determine
the volume of solder that will be under it at that height.
Ben
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Kane, Amol (349)
Sent: Wednesday, May 07, 2008 8:09 AM
To: [log in to unmask]
Subject: [TN] Part floating on solder
Dear Technetters,
I am trying to determine if a small SMT QFN part (it has a rather large
center ground pad that needs to be soldered) is floating on the center
pad solder deposit. What is the value of solder surface tension (Sn-Pb)
that I can use with this? I am trying to balance the part wt with the
force due to surface tension to prevent floating.
Any help will be greatly appreciated.
Thanks,
Amol
WARNING: Export Control
This document may contain technical data within the definition of the
International Traffic in Arms Regulations (ITAR), and subject to the
Export Control Laws of the U.S. Government. Transfer of such data by
any means to a foreign person, whether in the United States or abroad,
without proper export authorization or other approval from the U.S.
Department of State is prohibited.
CONFIDENTIALITY NOTICE:
This e-mail, and any attachments, is for the sole use of the intended
recipient(s) and may contain information that is confidential and
protected from disclosure under the law. Any unauthorized review, use,
disclosure, or distribution is prohibited. If you are not the intended
recipient, please contact the sender by reply e-mail, and delete/destroy
all copies of the original message and attachments.
Thank you.
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0 To
unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or
(re-start) delivery of Technet send e-mail to [log in to unmask]: SET
Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the
posts: send e-mail to [log in to unmask]: SET Technet Digest Search the
archives of previous posts at: http://listserv.ipc.org/archives Please
visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for
additional information, or contact Keach Sasamori at [log in to unmask] or
847-615-7100 ext.2815
-----------------------------------------------------
---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 15.0
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815
-----------------------------------------------------
|
