Hi,
     We ran into a similar problem. We found that the shorts were actually
  null nets that had a piece of etch and a via attached to them. The
  connections were not listed in our IPC 356 netlist, but were listed as
  a connect in the Gerber derived netlist (a pin to via connection)...
  Therefore the netlists did not match.
    We did not have the problem until the supplier started using some
  some new software (or it could have been an upgrade).
     Did you investigate what the shorts were? You might find a similar
  problem.

  Feel free to contact me if you would like more info...

               Lynn Isaacson, C.I.D.,  Sr. PCB Designer
                     Medtronic Physio-Control
11811 Willows Rd. N.E., P.O. Box 97006 Redmond, Washington 98073-9706
           425-867-4443 Direct         425-867-4462 Fax

> X-Sender: kpatel@kms
> Mime-Version: 1.0
> Date: Wed, 1 Sep 1999 11:00:11 -0700
> From: Ken Patel <[log in to unmask]>
> Subject: [TN] Gerber v/s Netlist (IPC 356)
> X-cc: [log in to unmask]
> To: [log in to unmask]
>
> I am having a terrible time as my new supplier is asking so many questions.
> The main one is that netlist extracted gerber & provided netlist (IPC 356)
> are not matching and they are finding so many shorts. What's the problem
> here? It's a troublesome to ask old supplier these kind of questions as they
> might think we are taking business away from them.
>
> Do you think, our best bet will be to extract the netlist from the gerber?
>
> re,
> ken patel
> ______________________________________________________
> Ken Patel                       Phone:  (408) 490-6804
> 1708 McCarthy Blvd.             Fax:    (408) 490-6859
> Milpitas, CA 95035              Beeper: (888) 769-1808
>
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