I am now at the stage of releasing aPCB design to a manufacturer. I have designed a 4 layer board with the inner pair of layers designated power and ground planes. I noticed that when output -> Plotting & Printing is selected in the list of available layers, a new layer appeared called GND (Powerplane Positive)
Upon processing of this file, 'GND(Powerplane Positive)' contains the intended ground plane design whilst 'GND(Powerplane)' is a similar shape but not at all what I was designed? Is this a bug or is there something I'm missing?
No, -it's only to reduce Gerber file size. It's the "negative" image. Remember the old days when you only got 200KB on a floppy?
However past experience has shown that your better off using 4 "ordinary" layers and then flooding the inner two with Vcc and 0V. I.E. don't assign them as Powerplanes.
This way you cannot get isolated Vcc/0V areas surrounding dense vias/pads which the DRC didn't pick up. Not sure if this DRC bug is now fixed though, but why risk it?
Also make sure your Gerber set up (Options=>Gerber, then Format) specifies maximum resolution i.e. metric 3+5. The default setting is inadequate.
Creating PCB output
Posted - 11 Apr 2014 : 15:23:57
