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Subject: Re: [Homebrew_PCBs] Round to Square pcb

From: ron amundson <mnphysicist@...>
Date: 2004-08-28

--- Cristian <bip@...> wrote:

> SOOOOOORRRRRRY, my mistake.
> I've tried to attach the file.
>
> Is there any way to automatically convert the
> 'round' pcb to 'square' one,
> to allow to spare FeCl or milling bits.
> Cristian
>
>
You should be able to do so in your cad tool by
changing the library files.

However, if your board was for more than a quick
prototype, and subject to flex, thermal cycles, or was
a high performance design, square pads should
generally be avoided.

Ideally traces should have small fillets when they
connect to pcb connectors. It does help to reduce the
probability of cracked trace4s and intermittents down
the road. Now if your board is in a nicer environment,
its not an issue. One does have to balance this with
DFM, as wicking can create much headaches.

Square pads also can create less than desirable
performance at higher frequencies. It should be no
problem for DC or VLF.

Square pads also due not lend themselves to proper
guarding, as its hard to maintian a consistant
distance. Again more of a performance issue, and for
most it would make little difference.

Ron



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