I was doing a Radio UHF transmitter this month and having viaa in the ground place was mandatory. I finaly found that is is *very* simple:
* In this example, ground id mostly in the bottom layer * start a track in the botom layer from a nearby ground track * change layers so that a Via is added * double-click to end the track * go back to the bottom layer and do it again, many times :) It is fast enough, and easy. Alain Em 24-08-2010 09:33, James Moody escreveu: > > > A number of components I've come across lately (DC motor controller > chips, ESD protection devices, for example) have a thermal or ground pad > underneath the chip. This requires that a large pad be included in the > footprint, and the usual recommendation is that several vias are used in > this pad to connect it to the ground layer. This is also part of the > thermal management scheme. > > For example, if you look at page 10 of the datasheet for the Allegro > A4983, it describes how to lay out the board. It shows 9 vias in the > under-chip pad used to aid in solder flow and heat transfer. > > My first thought for how to do this in KiCad was to define a bunch of > vias on the board. My second thought was to change the module so that > the large pad was actually several small pads butt up against each > other, tiled together to make one large pad, and have each pad be a > through-hole style pad with a very narrow drill. > > Is there a better approach or feature I've missed? > Thanks. > --Jim
