Via's in pad can cause some problems in manufacture. If you can avoid it, you should. If you cannot avoid a via in pad structure, you could reduce some manufacturability problems by requesting that the vias be filled with Silver / Epoxy, talk to your PCB manufacturer to see if they can help there. If it is a blind microvia, you can still have solderability problems for a BGA ball where a air pocket could form. I have done it, but not on purpose ! Karl From: Dave Schaefer <[log in to unmask]> Reply-To: "(Designers Council Forum)" <[log in to unmask]>, Dave Schaefer <[log in to unmask]> To: [log in to unmask] Subject: Re: [DC] VIA in Pad Date: Fri, 25 Jun 2004 10:37:47 -0500 If "Via in Pad" refers to laser microvias, this is a fairly common practice, and likely everyone owns a product (digital camera, cell phone, camcorder) than uses this type of design. If properly designed and fabricated you should have no problems manufacturing the assembly. Check the DC archives, as there's probably a wealth of information on the subject. Dave -----Original Message----- From: DesignerCouncil [mailto:[log in to unmask]] On Behalf Of Tom Parkinson Sent: Friday, June 25, 2004 10:14 AM To: [log in to unmask] Subject: [DC] VIA in Pad We're a CM. One of our customers is asking us to build a board assembly that will be using BGAs with VIAs in pads. They are in the design stages at this point, and we have some concerns with having a Via in the middle of a BGA pad. Anyone have suggestions and/or experience with this?? Thanks Tom Parkinson - Quality System Manager - CIT WinTronics, Inc. Ph: 724-981-5770 Ext. 235 Fax: 724-981-1772 ---------------------------------------------------------------------------- ----- DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF DesignerCouncil. To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 847-509-9700 ext.5315 ---------------------------------------------------------------------------- ----- --------------------------------------------------------------------------------- DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF DesignerCouncil. To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 847-509-9700 ext.5315 --------------------------------------------------------------------------------- _________________________________________________________________ Watch the online reality show Mixed Messages with a friend and enter to win a trip to NY http://www.msnmessenger-download.click-url.com/go/onm00200497ave/direct/01/ --------------------------------------------------------------------------------- DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF DesignerCouncil. To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 847-509-9700 ext.5315 ---------------------------------------------------------------------------------