Hi John, That is correct, see IPC SM-782 rev A amendment 2, section 14. Brent -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of John Guy Sent: Tuesday, May 10, 2005 12:59 PM To: [log in to unmask] Subject: [TN] BGA Ball/Pad Size Ratio Hello All, I was wondering if there is some guideline for the recommended pad size for a BGA based on the component's ball size? I have been told that it is recommended that the pad diameter be about 80% of the ball diameter, but I would like some confirmation. Thanks in advance, John Guy Surface Mount Process Engineer diversifiedsystems, inc. Custom Products Division 3939 W. 56th Street Indianapolis, IN 46254-4961 Telephone: 317-299-9547, x336 Fax: 317-298-2055 E-mail: [log in to unmask] Web: www.divsys.com --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 ----------------------------------------------------- **************************************************************** The information transmitted in this message is confidential and may be privileged. Any review, retransmission, dissemination, or other use of this information by persons or entities other than the intended recipient is prohibited. If you are not the intended recipient, please notify Analogic Corporation immediately - by replying to this message or by sending an email to [log in to unmask] - and destroy all copies of this information, including any attachments, without reading or disclosing them. Thank you. --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e 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 -----------------------------------------------------