Right. That has been my experience also. But for .5mm, things get a
little tougher.
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of David Greig
Sent: Friday, March 02, 2007 11:35 AM
To: [log in to unmask]
Subject: Re: [TN] BGA footprint
Richard,
For TI's 0.8mm lead free BGA's, I know from my own experience that a
0.38/0.40mm NSMD land gives better results, rather than their suggested
0.35mm.
This is for 532 ball DSP's that I've been designing in recently.
Best Regards
David Greig
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Stadem, Richard D.
Sent: 02 March 2007 17:09
To: [log in to unmask]
Subject: Re: [TN] BGA footprint
Hey, Kim, thanks!
This is good info. To make it easier to find for others who may be
interested, I have included a direct link to the document with the pad
design information for a .5mm pitch design. Look at the Reliability
section also. Lots of good information.
http://focus.ti.com/lit/an/ssyz015b/ssyz015b.pdf
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Haynes, Kim
Sent: Friday, March 02, 2007 10:42 AM
To: [log in to unmask]
Subject: Re: [TN] BGA footprint
Check www.ti.com and enter microstar in the text search box. There are
several papers on small pitch BGA devices and the PCB designs to make
them usuable. The thermal issues may also be important in a CSP.
Good luck,
Kim
________________________________
From: TechNet on behalf of Bob Perkins
Sent: Thu 3/1/2007 6:36 PM
To: [log in to unmask]
Subject: [TN] BGA footprint
Hi
I am working on a new board with a 0.5mm pitch BGA and I am wonder if
someone can advise me on the footprint.
1) the datasheet says the solder ball is 0.3mm +/-0.05mm
2) IPC recommends to use 80% of ball diameter for the pad which would be
0.24mm
3) Would it be OK to use a 0.2mm pad? I am hesitant to go against
recommended size without some corroborating documentation. The reason I
would want to use 0.2mm pad is to avoid using via-in-pad.
I am curious if IPC defines footprints based on what is good for
manufacturing or is it simply theoretical?
Thanks
Bob
---------------------------------------------------
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
-----------------------------------------------------
---------------------------------------------------
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
-----------------------------------------------------
--
Virus scanned by Lumison.
---------------------------------------------------
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
-----------------------------------------------------
|