MOSFET shipped in non-ESD conductive foam

[blueskull]

I always have good experience with major distributors in terms of how they protect the parts, but not this time.
This time, I got 2 MOSFETs in pink foam, the foam is tested with a UniT 2.5kV insulation meter, and shows ~13G resistance -- not exactly ESD conductive.
Usually I expect the foam to be <10M resistance to effectively protect parts, just like those black foams.
Also, the blue-greenish plastic bag is completely non conductive.
BTW, Mouser's TO247 tube is also not quite conductive -- ~5G. ESD-dissipative, but not exactly ESD-conductive.
Mouser's MOSFET foam is better -- standard black foam, <10M resistance.



Any idea how this happens from Digikey? Any similar experience to share?

[sleemanj]

I seem to recall Dave (I think, maybe it was somebody else) got some stuff from Digikey (I think it was) once that was not properly packaged for ESD also, they apologised for the error and replaced it as I recall.

I would certainly expect FETs to be shipped in metalised bags, "pink foam" inside such bag would be OK. 

Pink foam inside a non-shielding bag, nah don't think that's good enough from Digikey, that's barely better than a typical Chinese vendor.

[thm_w]

Digikey will ship those blue ziploc bags inside of a metalized bag. I'm assuming you got that too, but didn't mention it?
I see no problem with this, assuming it came in the metal bag, but I think its a bit overkill.

VGs max rating is -8/+18V, 660pF, so I suppose it could be damaged if not handled carefully.

edit: I don't see it in this device, but a similar cree device had following ESD spec,

Code: [Select]

Test Circuit  Devices Sampled   Resulting Classification
ESD-HBM   All Devices Passed    1000V 2 (>2000V)
ESD-MM    All Devices Passed     400V C (>400V)
ESD-CDM   All Devices Passed   1000V IV (>1000V)

[sleemanj]

Digikey will ship those blue ziploc bags inside of a metalized bag. I'm assuming you got that too, but didn't mention it?

Correct, at least they did this part right. Anyway these parts are not needed anymore due to a design change.

In that case, that's fine, assuming the "blue bag" is dissipative. 

No static will be generated inside the metalized bag, and the metalized bag prevents static discharge from outside the bag getting inside the bag.

It seems wasteful to double bag it though.

As for Chinese sellers, I'm just happen when parts arrive if they are not glad wrapped (saran wrap, depending on your part of the world) onto a rapidly deteriorating and static clinging to everything polystyrene block.

[tautech]

I always have good experience with major distributors in terms of how they protect the parts, but not this time.
This time, I got 2 MOSFETs in pink foam, the foam is tested with a UniT 2.5kV insulation meter, and shows ~13G resistance -- not exactly ESD conductive.
Usually I expect the foam to be <10M resistance to effectively protect parts, just like those black foams.
Also, the blue-greenish plastic bag is completely non conductive.
BTW, Mouser's TO247 tube is also not quite conductive -- ~5G. ESD-dissipative, but not exactly ESD-conductive.
Mouser's MOSFET foam is better -- standard black foam, <10M resistance.



Any idea how this happens from Digikey? Any similar experience to share?

Contact them and have a real good bitch about it.
That sort of behaviour is typical of some eBay and Aliexpress suppliers but I insist that they supply static sensitive devices in proper antistatic packaging and there's no good reason why Digikey should lower themselves to the same level. 
For eBay and Aliexpress sellers I give them fair warning that products need be provided in ESD packaging or negative comments will be placed or a case taken against them. I've even sent them ESD guideline pdf's to make clear what's expected.

Some ESD foam I get from E14 measures 130K , tips ~25mm apart.
#1687855
http://nz.element14.com/multicomp/038-0016/high-density-foam-305x305x6mm/dp/1687855?exaMfpn=true&categoryId=&searchRef=SearchLookAhead&searchView=table&iscrfnonsku=false

It's a Multicomp product #038-0016 and cheap. 

[metrologist]

I would be happy if my eBay order came in on a pink foam -- at least better than just floating in a plastic bag.

I got loose parts floating in a bubble padded envelope, with some pins sticking out and folded over!

[TheSteve]

I've received fet probes just stuffed in a cardboard box from an ebay purchase, and when I bought a PGA pin Intel processor it was just stuffed in a cardboard envelope. I had to straighten 20+ pins but really it is a miracle it survived at all.