kicad-developers team mailing list archive

[Vesa Solonen <vesa.solonen@xxxxxxxx>]

26/11/14, 21:16, Nick Østergaard kirjoitti:
> 2014-11-26 20:00 GMT+01:00 jp charras <jp.charras@xxxxxxxxxx>:
>> Le 26/11/2014 18:43, Nick Østergaard a écrit :
>>> This is indeed an annoyting bug, it has existed since 2009 at least.
>>> There is already a bug report about it. See:
>>>
>>> https://bugs.launchpad.net/kicad/+bug/1035621
>>
>> Sorry, but I already said why a trapezoidal pad is designed.
>>
>> The fact an user is thinking something is not expected is not a proof of
>> a bug.
> 
> I do follow you, but I still thought it was worth linking this thread
> with the bug report.
> 
>> Trapezoidal pads have a very specific purpose.
>> I am pretty sure a copper zone around tracks in a microwave design
>> breaks the design.


>From an user perspective if xyz pad shape is supported, it should be
supported without artificial limitations. No tool designer may know how
an innovative user uses pad shapes.

The fact that a trapezoidal pad is usable to decrease reflections near
package should not limit it's usefulness for optimisation of, say wave
soldering.

If such shape is used for gradual impedance scaling, the fill keepout
must follow anyway or be far enough not to matter regarding the
transmission line properties. Just the fact that current state leaves
pads unconnected is enough to mark behavior as a bug. Pad left
unconnected from the assigned net is a serious no-no.

I've also used trapezoidal pads for the purpose stated by Jean-Pierre as
well as arc stubs. Thank you for all of the microwave tools!

-Vesa