Rod:
The guidelines we have established here are as follows:
        Total combined voiding <25%
        Less than or equal to 3 separate voids
        No two voids can intersect, irrespective of size/percentage

Another 2cents...

> -----Original Message-----
> From: Rod Martens [SMTP:[log in to unmask]]
> Sent: Wednesday, October 07, 1998 2:48 PM
> To:   [log in to unmask]
> Subject:      Re: [TN] Voiding in BGA
>
> I've never seen an exact number for voiding, but would be interested
> if anyone
> does have one.  As for personal experience, we have seen cases where a
> single
> large void or many small voids aligned at an interface negatively
> impacted the
> reliablility.  Also, we saw a case where some degree of voiding
> actually
> increased the life of BGA's, most likely due to some sort of crack
> arrest
> mechanism.  I would imagine that a good number for max. voiding would
> need to
> include not just % void, but also position in the joint.
> My $0.02,
> Rod Martens
>
> -----Original Message-----
> From: Non-HP-FEiranova
> /hp-ftcollins,[log in to unmask]
> Sent: Wednesday, October 07, 1998 2:39 PM
> To: Non-HP-TechNet /hp-ftcollins,[log in to unmask]
> Cc: Non-HP-FEiranova
> /hp-ftcollins,[log in to unmask]
> Subject: [TN] Voiding in BGA
>
> To all:
> Is there a specification to address the maximum voiding allowed
> for PBGA and CBGA solder joints attached to FR-4 substrate ?
> Can anybody share some personal experiences in this matter ?
> Thanks
>
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>  << File: [TN] Voiding in BGA.TXT >>

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