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Tony

#12781

No-clean for RAM | 28 January, 1999

Hi !

Does any one used no-clean solder paste for SDRAM product ? Please advise. TQ.

Tony

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Steve Gregory

#12782

Re: No-clean for RAM | 28 January, 1999

| Hi ! | | Does any one used no-clean solder paste for SDRAM product ? | Please advise. TQ. | | Tony

Hi Tony!

Yes I have...at a memory company I worked at in the past.

Let me guess why you would ask that...whatever you're building that uses SDRAM is not passing test, huh? At least not until you wash them, right? ...and it dosen't happen with everything either, only every once in a while.

We had the same thing happen with some Pipeline Burst Cache' modules that we built at a memory company I used to work at. One of the test engineers told me why that happened, but I can't remember exactly what it was. He was russian and his name was Boris (big suprise there huh?), he was pretty funny, actually flew on Soviet Bears as a tailgunner during the coldwar period. I remember him telling me; "Da modules no pass testink from da no cleenink, yoo must put da modules thru cleenink...why we no cleenik da modules?"...cracks me up when I think of his accent.

Anyways, Sandia Labs did a very complete study on the effects that no-clean residues have on high-speed designs, you might check that for some information if that's your concern. If that's not what you were looking for, then never mind...(GRIN) The reason I assumed that's what you were asking about is because I do know that syncronous dram performance is one of the few parts that can sometimes be affected by no-clean residues...

-Steve Gregory-

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