[SI-LIST] Re: Cross-hatched reference planes

  • From: "Lee Ritchey" <leeritchey@xxxxxxxxxxxxx>
  • To: "Jeff Seeger" <jseeger@xxxxxxxxxxxxxx>, si-list@xxxxxxxxxxxxx
  • Date: Fri, 6 Apr 2007 08:49:53 -0700

I think the venting that was mentioned in an earlier reply was from someone
who thought my responses were venting frustration with a bad practice in
PCBs. yes, it could be called venting, except for teh CAD departments who
have to try to make Gerber files that include this type of plane structure.

I don't know what the venting being discussed in this latest string of mail
referes to.

For those who saw my response as simple venting, I apologize.   For all
those engineers and designers who have been asked to create cross hatched
planes, maybe this helped.

For the record, the only fab shops I have seen ask for this in the last
five years are located in Southeast Asia.  Wonder why they do that?

Lee Ritchey


> [Original Message]
> From: Jeff Seeger <jseeger@xxxxxxxxxxxxxx>
> To: <si-list@xxxxxxxxxxxxx>
> Date: 4/5/2007 12:35:30 PM
> Subject: [SI-LIST] Re: Cross-hatched reference planes
>
> Andy wrote:
>
>  > what is "venting"?
>
> In built-up multilayers, which start with a traditional core
> laminate, subsequent dielectrics are applied in liquid or semi-
> liquid state.  Unbroken copper areas inhibit cure.  Relief is
> in the form of "vent" pads appearing as stray anti-pads, or as
> a cross-hatch shape.
>
> Sorry that carpal tunnel limits my replies.  Or maybe that's a
> good thing.
>
> Best regards,
>
> --
>
>       Jeff Seeger                         Applied CAD Knowledge Inc
>       Chief Technical Officer                  Tyngsboro, MA  01879
>       jseeger "at" appliedcad "dot" com                978 649 9800
>
> ------------------------------------------------------------------
> To unsubscribe from si-list:
> si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
>
> or to administer your membership from a web page, go to:
> //www.freelists.org/webpage/si-list
>
> For help:
> si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
>
>
> List technical documents are available at:
>                 http://www.si-list.net
>
> List archives are viewable at:     
>               //www.freelists.org/archives/si-list
> or at our remote archives:
>               http://groups.yahoo.com/group/si-list/messages
> Old (prior to June 6, 2001) list archives are viewable at:
>               http://www.qsl.net/wb6tpu
>   


------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field

or to administer your membership from a web page, go to:
//www.freelists.org/webpage/si-list

For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field


List technical documents are available at:
                http://www.si-list.net

List archives are viewable at:     
                //www.freelists.org/archives/si-list
or at our remote archives:
                http://groups.yahoo.com/group/si-list/messages
Old (prior to June 6, 2001) list archives are viewable at:
                http://www.qsl.net/wb6tpu
  

Other related posts: