delorie.com/archives/browse.cgi   search  
Mail Archives: geda-user/2015/10/13/11:18:41

X-Authentication-Warning: delorie.com: mail set sender to geda-user-bounces using -f
X-Recipient: geda-user AT delorie DOT com
X-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=gmail.com; s=20120113;
h=mime-version:in-reply-to:references:date:message-id:subject:from:to
:content-type;
bh=3TOPjbTy7+s+x3syl3ys+T799slVnVO/ceefhePsQ6Y=;
b=zFsF3aPpD5u8bG8rvWKKMHyxtpm4FeAshc2ImLhC0IQrPTQ8h1GQjUtvU3PrPrVQeC
tRKxhRlW8edrggqqxGLRN6rhuIBoA8c3vYlClgpxzvj6ckLjLSKsOzlAryxuPpPb8Sgy
YVqsL5bqW/TTmXRZXsbsxIinevh6jI7yCKtoRrZsHyvVkmZ/b5tTekA5nf3ktZP+8LbF
euSYqpOmhL8szCLdRYPeqwuSPfpQDxiALu3NGo2cNXHstLI12iZyrv2M6YjHlWDAEloY
9sPajcVJmSEOVW7qMF/KhEVYIJX/muX1r6N2YKLO704pNn6vN406d2yvbYtUIWNE0rem
T8zQ==
MIME-Version: 1.0
X-Received: by 10.112.64.72 with SMTP id m8mr14892940lbs.41.1444749496913;
Tue, 13 Oct 2015 08:18:16 -0700 (PDT)
In-Reply-To: <201510130632.t9D6WbG5008643@envy.delorie.com>
References: <1042003D-82E2-40F0-AB60-8186580C46AD AT noqsi DOT com>
<20151012220005 DOT GC11989 AT visitor2 DOT iram DOT es>
<20151013075427 DOT ebe071d65cbd1277d7f3c714 AT gmail DOT com>
<201510130632 DOT t9D6WbG5008643 AT envy DOT delorie DOT com>
Date: Tue, 13 Oct 2015 11:18:16 -0400
Message-ID: <CAM2RGhSm21apmuC0AaPP3hrfL-x8Wr=y=WRCjTfXra_nNCr4Ag@mail.gmail.com>
Subject: Re: [geda-user] A lesson from gnet-makefile
From: "Evan Foss (evanfoss AT gmail DOT com) [via geda-user AT delorie DOT com]" <geda-user AT delorie DOT com>
To: gEDA users mailing list <geda-user AT delorie DOT com>
Reply-To: geda-user AT delorie DOT com
Errors-To: nobody AT delorie DOT com
X-Mailing-List: geda-user AT delorie DOT com
X-Unsubscribes-To: listserv AT delorie DOT com

On Tue, Oct 13, 2015 at 2:32 AM, DJ Delorie <dj AT delorie DOT com> wrote:
>
>> I also agree about poor usefulness of auto placement. The firts
>> problem is the decoupling capacitors. Maybe it would work better
>> with autoplacement in several steps:
>>   1. Disperse components.
>>   2. Place decoupling capacitors.
>>   3. As a first approximation place tightly coupled components as
>>   groups which of curse may be very hard to define.
>>   4. Autoplace this group of components there the tightly coupled
>>   components may have to be fine tuned.
>
> Autoplace is one of those things that's easy to experiment with using a plug-in.
>
> It's also something that's very hard to "get right" algorithm-wise.
>
> Heck, even a plugin that auto-selects bypass caps would be a
> considerable challenge, but very useful.

There should be an initial autoplace to just drop stuff on the page
and then a re-placement when the autorouter considers trace
lengths/impedances. This is not just a factor for bypass capacitors.

> I did one project where bypass caps had their own refdes (CB instead
> of just C) and were numbered according to the pins they went with, but
> that project only had one big IC on it anyway...



-- 
Home
http://evanfoss.googlepages.com/
Work
http://forge.abcd.harvard.edu/gf/project/epl_engineering/wiki/

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019