Yuan,
 Reading again carfully through this para.(4.3.2) it is not explicit
about BGA coplanarity.
 It was my assumption since the document mainly deals with BGAs.

 Mickey

LI YUAN wrote:
>
> Mickey,
>
> I don't have a J-Std-013 handy now. I believe it states that the 4-mil
> spec. applies only to the leaded components, i.e. QFP while the spec. for
> BGAs is 8 mils. Could you verify this?
>
> Thanks,
>
> Yuan Li
> Research Associate
> CAMPmode (Center For Advanced Manufacturing and Packaging of Microwave,
> Optical and Digital Electronics)
> University of Colorado at Boulder
>
> On Tue, 30 Dec 1997, mickey weiner wrote:
>
> > Dennis Fall wrote:
> > >
> > > I was wondering if there is an industry standard for coplanarity of
> > > solder spheres on a BGA package.  Any insight will be greatly
> > > appreciated.
> > >
> > > --
> > > Dennis ,
> >    I find in j-std 013 (4.3.2) that accepted coplanarity throughout
> >    the component lead configuration is 0.1 mm (4 mils).
> >    It does not specify if it takes into account both ball variation
> >    as well as substrate's bow & twist.
> >
> >    Season's Greetings to everybody on TechNet
> >
> >     Mickey
> >
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