Yes, I understand the reasoning, but still wonder about the risks.
(The new 2222A refers to the "likelihood for blistering, warping,
or heat shielding...")
Warpage and the need for a balanced construction are high on the
list of critical DFM, but was wondering if anyone out there sees
problems with unhatched planes, ever. (That's why I CC:TechNet,
there are people here who see a LOT of board designs, and I don't)
Is anyone REALLY using hatched planes? (other than for flex?)
thanks for responding,
Jack
.
On Wed, Jul 29, 2009 at 7:32 PM, Kenneth Wood <[log in to unmask]> wrote:
> Jack,
> The IPC-2222 says that large areas "may" be broken up.
> This standard's latest release is February, 1999 so it's a bit outdated.
> Years ago we used to do things like that to reduce file sizes but this is
> unnecessary today.
> A solid plane is better but be sure to balance out the copper on all layers
> to guard against warpage.
> I think the warpage issue is where the old IPC-2222 standard was going with
> the cross hatching idea.
> Ken
>
> _____________________________________
> Kenneth J. Wood
> Saturn PCB Design, Inc.
> [log in to unmask]
> www.saturnpcb.com
>
>
>
> -----Original Message-----
> From: TechNet [mailto:[log in to unmask]] On Behalf Of Jack Olson
> Sent: Wednesday, July 29, 2009 7:19 PM
> To: [log in to unmask]
> Subject: [TN] Hashing-Out Hatching
>
> Greetings,
>
> I was just reading through the latest draft of IPC-2222,
> and stumbled into the advice in section 10 regarding
> "large conductive areas", where we are advised to
> use some kind of etched pattern (cross-hatching)
> for any area larger than a 25mm diameter circle.
>
> I have done this exactly once in the last 22 years,
> does anyone else do this?
>
> Has anyone ever experienced a problem by NOT doing
> this? (not counting soldermask over HASL)
>
> Jack
>
>
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