At 12:45 AM 7/24/2009, Rex Waygood wrote:
>Ummm. Not being an expert here but having seen sections of microvias I
>would be inclined to put in a large safety factor.

Ummm, unless they're conductive paste vias I wouldn't be too worried. :-)

uVias are short and have all sorts of intimate contact with other 
copper and materials that sink off heat.

Empirically, when we've done simulations/models and compared to 
actual builds they run much cooler.

>Regards
>Rex
>
>-----Original Message-----
>From: TechNet [mailto:[log in to unmask]] On Behalf Of Dwight Mattix
>Sent: 23 July 2009 19:53
>To: [log in to unmask]
>Subject: Re: [TN] uVia Capacity
>
>IPC-2221 figure 6-4 "Conductor thickness and width for internal and
>external layers."
>
>Use the magic of pi to figure the equivalent flat trace width, check vs
>the charts and voila!  If it's a solid copper filled uVia then look for
>round wire equivalent.
>
>At 10:32 AM 7/23/2009, Kenneth Wood wrote:
> >Hi,
> >
> >Does the IPC, or anyone, have current capacity numbers for micro vias?
> >
> >Thanks
> >
> >Ken
> >
> >
> >
> >
> >
> >
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