This is a multi-part message in MIME format.

------=_NextPart_000_002E_01C6D8AE.13C49FC0
Content-Type: text/plain;
	charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable

> > With some care it could be setup where a solder bridge can=20
> > connect any pin
> > to either of the 'power planes', pull up or pull down=20
> > resistors could be
> > added to any of the pins (or fixed voltage dividers if you=20
> > added both) or
> > bypass caps. Lot's of flexibility without adding cost.
>=20
> I like that idea, but I don't see how it can be done. Do you imagine =
TH
> or SMD for those pull-up/downs and caps? TH would occupy a lot of =
space
> (makes the PCB too wide), I don't see how SMD could offer the choice =
of
> ground/power (unless you want to dedicate both sides for this =
purpose).
> Oh, and there are chips with multiple powers....
>=20
> Wouter van Ooijen
>=20

Wouter, I just sent you my Eagle file of what I was thinking, but here's =
a little corner so we can all see it. The top layer is exactly the same =
as before, I just added some planes and pads to the bottom layer.

Each pin connects to two surface mount footprints, the other side of =
each one connects to it's common plane. The larger plane covers most of =
the center of the board and the other is a ring around the perimeter. I =
drew a new library part for this, it's basically a universal SMD =
discrete pattern. The two pads are about 0.012" apart, which should be =
close enough to solder bridge. And the pads are big enough to accept =
parts as large as 1206, so it should take anything a person might want =
to hand solder :-)

In use I envision a process like this- Since both planes are uncommitted =
- declare one power and the other ground. Add solder bridges to connect =
all the power and ground pins to their respective planes, add decoupling =
caps to the sets of power pads that didn't get bridged. Add pull up or =
pull down resistors to any pins that need them.

-Denny
------=_NextPart_000_002E_01C6D8AE.13C49FC0
Content-Type: image/gif;
	name="adapt.gif"
Content-Transfer-Encoding: base64
Content-Disposition: attachment;
	filename="adapt.gif"
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------=_NextPart_000_002E_01C6D8AE.13C49FC0
Content-Type: text/plain; charset="us-ascii"
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist

------=_NextPart_000_002E_01C6D8AE.13C49FC0--