Quick Xono Question

[Freddie]

peranders,

There is no schematic for the XOno on the Passlabs site. There is a schematic for the Aleph Ono though.

[HarryHaller]

Printed circuit board houses like this since they can recover more copper during the etching process and save some money. It also allows better adhesion for the solder mask and less chance of bubbles forming between the solder mask and the copper during soldering. There is also less likelyhood of the board warping during automated wave flow soldering or convection soldering for SMT.

I had to negtiate with my manufacturing engineer on all these issues on my last telecom board that needed solid ground plans for tecnical cosiderations. Not a triviail endeavor since we were building over a million boards per year in a extremely cost sensitive market place. Most CAD systems will let you add this cross hatching in the design. I would be surprised if cometics entered in to it other than the solder mask issues and I think a solid plane is nicer looking anyway, but different strokes for different folks.

"I have read somewhere that a solid groundplane ALWAYS is best in electrical terms. It's also an advantage when you make pcb's. It's good to have as much copper as possible in order to get even thickness of the plated copper (only pcb's with plated through holes)."

In most cases the hatched plan is very close in terms of AC impedance to the soild one and is not worth the fabrication tradeoffs I have outlined. I have spent some time lookin at this.
I have never run into the plating issue or real any thing about it.
Sincedecent board shops can reliably plate trough holes on six mil traces I can't image it being an issue.

http://search.barnesandnoble.com/boo...-2002+11:27:51

H.H. (Hesitant to Hatch)

[peranders]

The manufacturing process seems not be an issue for us (me in my work), nor the warp thing. We make rather small pcb's and not millions....

Is the boxed Xono the same as Aleph Ono?

[jam]

Similar but not the same. Regulator and circuit board layout are different. X Ono sounds much better.

Jam

[Karen]

Regarding the cross-hatched ground plane, if I know Nelson at all one good reason for using this method is that it is swell for the environment. Conserves material and better in a hundred years when the amps end up in a land fill. ( I meant a thousand years)

Also please try:



http://passlabs.com/prodlit/xonolit.htm for pictures of the production Xono boards. Thanks

[wayne]

I like the looks of a cross hatch. I have seen warping with solid especially on one side only. The preheat profile is also easier on a cross hatch.