Electronics Forum | Thu Feb 03 07:39:24 EST 2005 | davef
The component orientation was just for the calculation. It has no affect on what you're seeing. As an alternate explanation, it's possible that difference in temperature is causing the board to flex in the z-direction [as you say, it may not be f
Electronics Forum | Fri Jun 20 10:27:19 EDT 2003 | Cristiano Dick Smiderle
Hi We are experiencing serious problem with ceramic capacitors. They are with low electrical resistence and the problem is intermittent. We found some of them with micro cracks but not all. What could be the causes for this problem? We are su
Electronics Forum | Fri Apr 18 16:53:25 EDT 2003 | takfire
DST, What was the crack signature? Was the crack parallel with the internal electrodes or 45� with the terminal electrode? It is also important to determine the orientation of the failed caps on the PCB (in regards to depaneling). Perhaps the cap
Electronics Forum | Fri Jun 25 08:38:37 EDT 2010 | mun4o
Thanks, Dennis. That is a good idea, but I have problem :) - our logistic department lookig for cheap components...What other mnfg of cap you use? Regards,
Electronics Forum | Fri Jun 25 09:18:23 EDT 2010 | flipit
Thanks, Dennis. That is a good idea, but I > have problem :) - our logistic department lookig > for cheap components...What other mnfg of cap you > use? Regards, The capacitor dielectric material might be something you could look at also. COG,
Electronics Forum | Mon Feb 07 08:34:46 EST 2005 | Dougs
we are still looking into possible causes, we have rigged up a test to determine whether the cap is cracked and have ran a controlled batch off of SMT, these were all tested and look OK. I'm looking into buying some small strain gages to place over
Electronics Forum | Mon Jul 07 11:45:45 EDT 2003 | lromero
Do you know what the maximum temperature rating is for the devices. But in my past experience you could be seeing the following. Excess thermal ramp rates typically you would like to see 2 to 3C/sec in the reflow oven, if it is greater than this i wo
Electronics Forum | Wed Jun 24 18:41:23 EDT 1998 | Bill Chrisitian
| Dennis, thanks for your input. I myself can't remember having any caps fail due to thermal stress/cracking. But the guru's here says it happens and since the assembly is for space flight, it's a requirement to preheat. Also, your process is exactl
Electronics Forum | Thu Jun 25 11:53:09 EDT 1998 | Dave F
| | Dennis, thanks for your input. I myself can't remember having any caps fail due to thermal stress/cracking. But the guru's here says it happens and since the assembly is for space flight, it's a requirement to preheat. Also, your process is exac
Electronics Forum | Fri Jul 09 19:09:52 EDT 2010 | rway
A couple of things: Does the cap break if you try to remove it with hot air? If not, than you are breaking the caps do to mechanical stress. We have had similar issues. I don't think your board is suffering from mechanical stress from depaneling o