X-Authentication-Warning:	delorie.com: mail set sender to geda-help-bounces using -f
X-Recipient:	geda-help AT delorie DOT com
X-Original-DKIM-Signature:	v=1; a=rsa-sha256; c=relaxed/relaxed;
	d=gmail.com; s=20210112;
	h=mime-version:references:in-reply-to:from:date:message-id:subject:to;
	bh=Wd/aNsKK98oZJa25NZuZX948U8MD3ZqIscj+lRDV/+I=;
	b=bcotnUX25YOTwF6q+bdR4nHqFHOjtk45WS+t/4IBbvjghZ2omoLqkkde7VuOjzwKR2
	SHX1cN276DOf33dFgD/2nYGFMrZ6TKxeaHL05Va3XLgKgfeNWEx+6PNj1GlvQtBQfQRN
	IJWRJTfThtx6PMcsTDd/hgWzynpb9PnBlhwwHJlP0cz/fsgWINDDxE4egN4wqcArQSSQ
	UYM5i6etxflDWFYc0wSXSNbGU2F5ozg0qsFnR/ePjjyStr5Z9abOxFGNLEoekZdyeHwS
	i+k7foTzmZWonWdeF3AIYMJQ61S+TbCholMAFFP4m/qOI84iPUk5Z4zEK7PsU/6XEoS9
	lHZw==
X-Google-DKIM-Signature:	v=1; a=rsa-sha256; c=relaxed/relaxed;
	d=1e100.net; s=20210112;
	h=x-gm-message-state:mime-version:references:in-reply-to:from:date
	:message-id:subject:to;
	bh=Wd/aNsKK98oZJa25NZuZX948U8MD3ZqIscj+lRDV/+I=;
	b=7AccWUcYRi1gkbmtptM3Q/ZLZ41EgurprWjEh5F8DcPQ2ErZZ6rDD88cpiCxMPpaCi
	G9LUq0AXwHP7sdBUKnvkFhx7ILNJkenuicB92CHkV6tEh+K+WHs7HMuEi/76pfNEMWzC
	zJ+d2rSlaaMigXmIySOGwAL5KalYzRyOLMNnnSuCM+lYexD/VrxDsBALwpLROVgrOuao
	KJVo6R3ZlAvOUJ1fUp2Kh+BByhxu6gENZw5MHGmP0CUrKawvLWST/ON6znRUfiGNQcIm
	p56J8Yk/6H7/NwrhUsJUWxtl3//vmZ45vDIAqJVFXTNznVVc35qDeCpl1UcaXLLq3Twm
	olmQ==
X-Gm-Message-State:	AOAM531wW/3d5u6Z6O0xxqfgRtxPkp434zrTtYpCvDp4703NjldjtQAO
	P8jUtDV9+Vnrw+hXZEKCS9LLlM8vTvFUZT6f9ARL+CKlptk=
X-Google-Smtp-Source:	ABdhPJy5nYgg1YMVF6iVDzFC5lSjYAdgryxnC7ydbK8F5hmaG8UOJs7SK5L1UAKKZ7Zsq19qrkH2PFuWxCwqkNIaJyE=
X-Received:	by 2002:a05:6512:782:: with SMTP id x2mr2299071lfr.183.1643277756899;
	Thu, 27 Jan 2022 02:02:36 -0800 (PST)
MIME-Version:	1.0
References:	<495872f6-0679-512e-4699-bec292f8da70 AT gmx DOT de>
In-Reply-To:	<495872f6-0679-512e-4699-bec292f8da70@gmx.de>
From:	"Erich Heinzle (a1039181 AT gmail DOT com) [via geda-help AT delorie DOT com]" <geda-help AT delorie DOT com>
Date:	Thu, 27 Jan 2022 20:32:24 +1030
Message-ID:	<CAHUm0tN41Ym=7O18A90YHPA-F=idx5OkHLB9Pm=ykZMJ=8_-5w@mail.gmail.com>
Subject:	Re: [geda-help] geda pcb: footprint with non rectangular pads
To:	"Vladimir Zhbanov (vzhbanov AT gmail DOT com) [via geda-help AT delorie DOT com]" <geda-help AT delorie DOT com>
Reply-To:	geda-help AT delorie DOT com

There appears to be a range of recommended land patterns for the VQFN
20 3.0x3.0.0.9 mm Microchip ICs.

https://www.microchip.com/en-us/support/package-drawings

Some of them have rectangular pads.

If you want to have arbitrary polygons in footprints, you may wish to
implement the footprint in pcb-rnd, as it allows a polygons to be
drawn and used as the copper shape in a custom padstack. You will not
be able to successfully export the footprint to gEDA PCB as there is
no internal support in gEDA PCB for polygonal SMD pads.

Similarly, pcb-rnd allows custom polygons to be specified for the
various apertures, i.e. soldermask, stencil, etc, or they can be
autogenerated in the padstack property editor.

translate2geda has to skip non rectangular or circular polygonal pads
when converting to gEDA PCB because there is no easy way to draw the
polygonal pad shapes.

It is worth mentioning the tutorial

http://www.penguin.cz/~utx/pstoedit-pcb/

which shows conversion of pdf or postscript land patterns to gEDA PCB
footprints using the pstoedit utility.

As of version 3.76, pstoedit also supports export to pcb-rnd's native
footprint format, allowing to export paths as well as polygons.

http://www.calvina.de/pstoedit/changelog.htm

Regards,

Erich.

On Thu, Jan 27, 2022 at 6:20 PM Klaus Rudolph (lts-rudolph AT gmx DOT de)
[via geda-help AT delorie DOT com] <geda-help AT delorie DOT com> wrote:
>
> I want to create a board with a VQFN 20 package which has non
> rectangular pads.
>
> A detailed drawing can be seen here:
> https://ww1.microchip.com/downloads/en/DeviceDoc/ATtiny806_1606_Data_Sheet_40002029A.pdf
> Section 34.2 20-Pin VQFN
>
> As you can see, the pads at the corner have a non rectangular shape.
>
> I read http://pcb.geda-project.org/pcb-cvs/pcb.html#Library-Creation
> and there was mentioned:
>
> 10.2.1 Creating Newlib Footprints
> "Currently a rectangle or polygon may not be used as a pad. "
>
> Is there any chance to create a footprint for PCB for VQFN-20 as given
> in the above linked data sheet with non rectangular pads?
>
> Thanks
> Klaus
>

- Raw text -