I was not talking about a solderability issue, but a lack of any wetting to the bottom of the part.

-----Original Message-----
From: Vladimir Igoshev. PhD [mailto:[log in to unmask]] 
Sent: Tuesday, December 24, 2013 11:35 AM
To: Stadem, Richard D.
Cc: [log in to unmask]
Subject: Re: [TN] IPC-A-610E, Voids in Thermal exposed pad of QFNs

Hello Richard,

I might be wrong but I don't think one can call a "slit" or a gap between a surface and solder a void. the situation you refer to is rather a solderability issue with a QFN pad, but not voiding one.

And if that is the case then, yes, you are absolutely right it's not detectable by X-ray. however, if it's a solderability issue then  it should spread over the affected batch, not just one QFN and it's always the best practice to qualify (by X-sectioning) any new batch of any or at least the most vulnerable components.

--
Best regards,

Vladimir Igoshev. PhD                          mailto:[log in to unmask]

SENTEC Testing Laboratory Inc.
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