Electronics Forum | Mon Dec 02 09:47:54 EST 2002 | davef
Most modern spec do not distinguish between process methods. So, there is no allowance "if you are using bla bla bla method, you should see ... . But if you are using bla bla de bla method, ignore that and look for ... ." Most specifications requi
Electronics Forum | Thu Jan 16 15:55:31 EST 2003 | MA/NY DDave
Hi I have a funny feeling that Mike Konrad and I know each other from IBM-Endicott days, yet I could be wrong. It would be funny?? Mike gave a good answer. The Rosin or Rosin Mildly Activated Flux (RMA) if on the board at ICT (In Circuit Test) wil
Electronics Forum | Mon Jan 20 17:42:45 EST 2003 | jonfox
Double check the data sheets for your paste. Just as an example, ou Indium paste has a recommendation for the Heating, Liquidus, and Cooling stagees of reflow. They recommend a linear ramp up of 0.5 to 1.0 degree C. In the Liquidus stage, a peak t
Electronics Forum | Mon Feb 03 22:48:00 EST 2003 | vinesh
Hi all, We are using small CSPs (10x10mm) in one of our products which has a big ground pad in the center (7x7mm). The maximum voiding allowed on this big pad is also no greater than 25% which we are finding very hard to achieve. The centre pad ha
Electronics Forum | Thu Feb 06 14:47:50 EST 2003 | MA/NY DDave
Hi "some customers/designers want to have via holes to be present in the PCB pad, due to some belief that it helps in heat dissipation. " As I think about this I don't know exactly why they would be concerned. I can imagine in some exotic products
Electronics Forum | Sat Mar 08 21:31:17 EST 2003 | MA/NY DDave
Hi Yes DavidF I agree, and that is what I think I am reading in the orginal and follow on post from the poster. I think this problem is just below full failure to solder which was your point, I think. You, and I particularly, are taking opposing y
Electronics Forum | Wed Apr 09 05:55:05 EDT 2003 | Chrissie
We've encountered a little problem with BGA's. There was a process problem in the build of the boards which has ment the BGA are failing open circuit due to the lack of solder paste. Any-one else had this problem? Any suggestions on solutions? We've
Electronics Forum | Fri May 02 12:41:16 EDT 2003 | Chris Lampron
Hi Chris, I had worked for a flex circuit house for 10 years. You should be able to follow your solder paste guidelines for times and temps. You may want to consider pre-baking the flex if it is made with Kapton. Kapton is Hygroscopic and will delam
Electronics Forum | Wed Jun 04 14:33:28 EDT 2003 | joeherz
CAL, Thanks for the input. When I said chemistry I was refering to soldering chemistry and not cleaning. I believe this machine has the capability to incorporate a saponifier but would prefer not to run in this manner. Running a closed loop DI re
Electronics Forum | Thu May 06 19:56:30 EDT 2004 | bruceatknoll
Here is some more info with regarding my Wave. 1. PCB .065" thick 2. leed length .20" (.135" protrution) I know this is high but we use many thousands and cutting each is not practical. 3. no clean flux by way of foam fluxer 4. wave machine is a HOL