Electronics Forum | Tue Aug 22 16:02:07 EDT 2000 | Dr. Ning-Cheng Lee
If the thermal mass of the products is small, a tent-shaped profile is recommended, with peak temperature around 240C. The hottest spot on board should be less than 250C. However, if the thermal mass of the product is large, such as a large server PC
Electronics Forum | Tue Oct 12 16:08:44 EDT 1999 | Brian
| I need your help! We have been doing double sided surface mount for 4 years now. Up until 6 months ago I have not had a tombstoning problem. Since then I have a fairly high incidence rate of tombstones on the 0603 size resistors (no other parts).
Electronics Forum | Fri Oct 08 16:36:59 EDT 1999 | Dave F
| We've recently encountered this problem where one of our .050" pitch BGA's were reflowing at the wave thus causing shorts... The board was profiled with probes stuck to a QFP solder joint, an 0603, and one of the BGA joints. There was an almost 7
Electronics Forum | Thu Sep 02 16:06:33 EDT 1999 | Earl Moon
| Has anyone done or seen any studies done documenting what may be the affect of hardware such as screws in the parimeter vicinity of BGAs on a circuit board? | | What I'm really after is anything describing how close a screw/washer/nut combination
Electronics Forum | Wed Jun 09 17:29:59 EDT 1999 | Earl Moon
| I am starting a new project which involve 3 oz copper layer with 20 mil components on the top of the board and 0.040" thick copper with D2Pak on the bottom of the board. | There is anybody has experience on metal-based PCB reflow process? I guess
Electronics Forum | Thu Jun 10 11:23:10 EDT 1999 | Gang Pan
| | I am starting a new project which involve 3 oz copper layer with 20 mil components on the top of the board and 0.040" thick copper with D2Pak on the bottom of the board. | | There is anybody has experience on metal-based PCB reflow process? I g
Electronics Forum | Wed Jun 02 09:50:00 EDT 1999 | Earl Moon
| Hello all | I have a question concerning whether or not there is any special requirements to follow for assembly of a Polyimide PCB card. The customer has the following information on there documentation but since we have never built anything with
Electronics Forum | Fri Feb 05 09:22:25 EST 1999 | Dave F
| | | Joni: What is it about your situation with the board/component/process that makes you want to explore alternatives? Dave F | | Dave: In our case the component is placed on metalled footprint which has via holes to transfer the heat via hole
Electronics Forum | Thu Dec 03 13:39:52 EST 1998 | Russ M
| | | | I have some 1.25 mils Al wire bonding chip on board process. After epxoy-based encapsulation, I do some aging test. How can I "see" or prove that there is a "wire break" exist due to the tension of thermal cycling? How can I know the failure
Electronics Forum | Tue Aug 25 21:01:45 EDT 1998 | Peter
We use an Intermec 3240 Thermal transfer printer and print on polyimid label material that survives the reflow and wave solder (top side only) process without turning black. Labels run around 3-4 cents per depending on the size (We found Imtec label
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