| ID: | 709 |
| From: | ge...@igor2.repo.hu |
| Date: | Tue, 30 May 2017 14:21:57 +0200 (CEST) |
| Subject: | Re: [pcb-rnd] up next: subcircuits (a.k.a. footprint model |
| in-reply-to: | 707 from John Griessen <jo...@cibolo.com> |
| replies: | 710 from John Griessen <jo...@cibolo.com> |
On Tue, 30 May 2017, John Griessen wrote: > On 05/30/2017 01:21 AM, gedau@igor2.repo.hu wrote: >> our new footprints will be capable of hosting: >> >> - arbitrary shaped pads drawn as lines and polygons >> >> - arbitrary shaped copper objects not being pads; a.k.a. pcb antenne; but >> this includes copper text or mask cutout text too; your >> company logo can really be a footprint >> >> - arbitrary mask cutouts, mask cutouts that are not derived from pads >> >> - arbitrary placement of paste; want a grid of paste blobbs on the center >> pad of your largish qfn? no need t emulate it with 10 >> pads, just draw them on the paste layer >> >> - slots or other cutouts/edge-contour-patterns; even the whole board shape >> can be a footprint >> >> - text and polygon on silk > > > This is going to open up use cases a lot. A subcircuit with an antenna loop > is going to reopen all the thought experiments > for how to handle the conflict of DRCs and a subcircuit/footprint with 2 pins > connected by a copper trace. Somehow we > need to label the "antenna loop" type of trace with an attribute that says > "It's OK if this is "shorted" at these two pins... > > Or... maybe the idea of netlist shorts gets pushed up from subcircuits to the > top level, and now the netlist is annotated to match > the reality of solid copper connection in a footprint-->short between > subcircuit pins 1 and 3 is part of the top level netlist. > Then the top level netlist has some footprints for chips that are an empty box > -- no info on whether the chip has shorts internally, plus some subcircuits > where internal shorts are transparent. So, the nets called ant1 and ant2 are > shorted together > and need to be a new net called ant1-ant2 with pins ant1, ant2. > Long term we are going to replace the whole DRC. We already have big parts of that code in production (for the advanced search). Such drc scripts will have no problem understanding an antenne loop. Short term we can add a temporary "no-drc" flag to one of the objects consisting the loop.
Reply subtree:
709 Re: [pcb-rnd] up next: subcircuits (a.k.a. footprint model from ge...@igor2.repo.hu
710 Re: [pcb-rnd] up next: subcircuits (a.k.a. footprint model redesign) from John Griessen <jo...@cibolo.com>
711 Re: [pcb-rnd] up next: subcircuits (a.k.a. footprint model from ge...@igor2.repo.hu
712 Re: [pcb-rnd] up next: subcircuits (a.k.a. footprint model redesign) from John Griessen <jo...@cibolo.com>