Electronics Forum | Thu Dec 26 12:12:55 EST 2013 | igorfo
Dear Friends, I need your help to understand requirements and measurement methods for bow and twist of assembled PCB (PCBA have and SMT and TH components). I already check all posts on the site but didn't found any related to my question answers.
Electronics Forum | Sun Jul 15 20:10:09 EDT 2001 | Danial
What is the best method to repair Warped PCBA. Obviuosly twisting it back to make it flat would be a disasterous. The method that I've tried wold be mounting the assembled board to the flat holder with the clamp and bake them at 120 Deg C for about 4
Electronics Forum | Thu Oct 14 20:42:07 EDT 1999 | Jeff Ferry
Grace, As deifned in IPC 7721 Procedure 3.2 Bow and Twist Repair "Bow and twist after soldering shall not exceed 1.5% for through hole PC boards and .75% for surface mount PC boards. The bow and twist shall not be sufficient to cause difficulties d
Electronics Forum | Fri May 07 20:08:39 EDT 2004 | Ken
...um also, don't forget that ther are planarity issues associated with BGA devices AND bow-and-twist issues with PCB materials. An example I have one BGA device that has a ball planarity of 7 mils!!! Ant that's the OEM specification! THis will re
Electronics Forum | Fri Jun 11 03:39:26 EDT 1999 | Gyver
| | | | Hello all! | | | | Recently we got a problem about the Funtional test. Some boards passed tests by using the auto-fixture(vacuum), but failed by using manual test fixture(need to plug CPU, DIMM etc.). The error symptom is no picture. We doubt
Electronics Forum | Mon Jun 14 14:30:42 EDT 1999 | Deon Nungaray
| | | | | Hello all! | | | | | Recently we got a problem about the Funtional test. Some boards passed tests by using the auto-fixture(vacuum), but failed by using manual test fixture(need to plug CPU, DIMM etc.). The error symptom is no picture. We d
Electronics Forum | Fri Jun 11 01:40:40 EDT 1999 | Gyver
| | | Hello all! | | | Recently we got a problem about the Funtional test. Some boards passed tests by using the auto-fixture(vacuum), but failed by using manual test fixture(need to plug CPU, DIMM etc.). The error symptom is no picture. We doubt it'
Electronics Forum | Wed Jul 12 05:04:01 EDT 2000 | JohnW
Hi Guy's.... Was thinkng about i more this moning..in the shower actually...sometimes think I do my best work there!. So far I'm looking at stuff like integrating the DFM study to show thing's that are going to present production / process issues e
Electronics Forum | Fri Jun 11 04:38:05 EDT 1999 | Gyver
| | | | | Hello all! | | | | | Recently we got a problem about the Funtional test. Some boards passed tests by using the auto-fixture(vacuum), but failed by using manual test fixture(need to plug CPU, DIMM etc.). The error symptom is no picture. We d
Electronics Forum | Mon Jun 14 09:16:58 EDT 1999 | Adam Pratt
| | | | | Hello all! | | | | | Recently we got a problem about the Funtional test. Some boards passed tests by using the auto-fixture(vacuum), but failed by using manual test fixture(need to plug CPU, DIMM etc.). The error symptom is no picture. We d
