PPM requirement

Guest

Folks,
On Qualification:
Stress used : EFR , 96hours

Question :
If we have company std for PPM (memory devices) = 333PPM, SS : 3000, A:1, R:2
Mechanical rejects were occured after stress, and 1 valid reject out of 2987 revealed during electrical testing.
This was resulted to 335PPM, (1/2987), would it be acceptable?

is this 2PPM can be resulted qualification failure? or any other option that we can use?

Any calculator to justify that this 335 PPM can be acceptable

Guest

if you think about it, only reason you're not meeting 333 ppm is because of your mech rejects. how bad is mech damage? if only bent leads, try to rework and get them tested. they might be test good and you can declare your qual as a 'pass.' by the way, i suggest you load a sample size bigger than 3000 next time, like 3020, because losing just one unit make you fail qual if you get one valid failure. re ur problem, ask your qa manager if qual is passed, because this is his call. gud luck...

siksik