Two sided PCB question

Jonathan

Hi All,

If one is laying tracks on the top of a two sided board, is it recommended to put a ground plane? On the bottom the entire board is ground plane and the tracks are little islands. Should it be the same on top?

Thanks!

Jonathan

Leon

It all depends on the application and how the board is being designed. A well designed PCB probably won't require copper pour on either side.

RDL2004

As Leon has said, it all depends. I always do it on my home made boards, but those tend to be low speed non-critical circuits and I do it mainly to save on etchant usage.

Here's a pretty good basic guide to pcb layout. The guy who wrote it is very experienced and has been in the electronics industry for many years. You may have heard of him.

http://www.alternatezone.com/electronics/files/PCBDesignTutorialRevA.pdf

tonyp12

As you don't want to etch away all that good copper, just having traces on the top would do that.

Having bottom as gnd is good as when you need to connect something to gnd you just apply a via.

Top pour could also be gnd or it could be Vdd
Or it could be a mix of them if you have RF or need to dissipate heat from a IC pad etc

Jonathan

Rick, great PDF. Very useful. You are doing two sided DIY pcb's?

Thanks for the replies. I am doing pretty simple boards and wondered if there was a standard. I like the idea of saving copper, although I'm not etching these boards. I have recently started the CAD route after years of DIY PCB's. I just never got things fine enough for todays small parts. I also like the idea of some copper for a heatsink, wish I had done that for the vreg on my last (and first CAD) board.

So much knowledge on these forums.

Jonathan