Re: gEDA-user: PCB package creation guidelines

[Steve Meier <smeier@xxxxxxxxxxxxxxxxxxx>]

In my land patterns I use the center of pad 1 as the centroid. I am
opposed to putting pad names into land patterns because that would make
patterns non reusable for different components. Do we really need one
land pattern for an so14 7400 and a second one for a 7402 and so on and
on. Now if we could get the pad name inserted into the netlist and then
inserted into the pcb file... that would be COOL.

Steve Meier


On Tue, 2004-11-16 at 09:14, Karel Kulhavy wrote:
> Hello
> 
> I suggest that some PCB package creation guidelines were created:
> 1) The centroid of the package must be really the centroid
> 2) The middle of the silkscreen outline outlines the biggest outline that
>    can occur.
> 3) The outline can go over pins and pads; it will be automatically masked
>    out
> 4) Each pin or pad should have a name so that 'd' and pinout window display
>    something meaningful
> 5) It's permitted to have a protrusion in the outline at pin 1, this protrusion
>    doesn't count for an outline.
> 
> Could you comment on this? Would your guidelines be different?
> 
> Would it be possible to add some description or something like that inside
> the packages which would describe for example what the package denotes?
> 
> For example I downloaded package outlines from Philips and Fairchild and they
> of course differed. Fairchild makes bigger outlines that Philips. So I made
> my own DIP16 package that could be described as "A package for Philips or
> Fairchild DIP16". One could put URL's with relevant specification into the
> description and the description could be displayed by some special key or
> meu entry in PCB and would be saved in the schematic.
> 
> Also m4 symbols could generate some special data field that could be displayed
> from the library window and would describe what should be exactly written
> into the gschem schematic. For example DIL:
> Macro name is DIL, $1 is number of pins, $2 is distance between the rows in
> mils.
> 
> Cl<