from the sounds of your enquiry, you are not overly experienced in
the use of CAD tools. If you were you would realize that this falls under
the concept of not trusting vendor supplied libraries (canned libraries). It
is almost a cardinal rule in EDA that you cannot trust canned libraries.
This is not a Protel issue, it is an issue with most every CAD library
supplied by a Vendor. This would fall under the requirement that one must
verify and ensure the suitability of any vendor supplied library
        As for the original comment from Brian, with the profusion of part
footprints from varied manufactures do you think it is possible to supply a
library with a default footprint that would cover all possibilities in a
suitable fashion. A word of warning might point out an issue for further
study on your part. Would all SOT23 devices fit one standard/global SOT23
footprint? Not a chance, in the professionally designed footprint standard
that our company uses there are over one dozen variations of a SOT23
footprint to cover all manufacturers and devices that they have encountered
over the life of their footprint design standard. Need a SOT23 footprint?
You had better pull out the manufacturers datasheets and ensure that you
have got exactly the right footprint for that manufacture and that
manufacturers particular part type (this does not even include the fact that
some manufacturers alter the pin numbering scheme around on SOT23s). In some
cases, a standard SOT23 footprint is not even a reality across one
manufacturers part offerings, depends on the packaging facility that
packaged the dies.

        As for your POT symbol/footprint problem, I have seen manufacturer's
parts specs that would have fit your symbol pin numbering (pin #3 is wiper).
So is the symbol you used wrong? No it was simply not the symbol which you
wanted to use. Assume nothing when it comes to vendor supplied libraries!
When you make a library part document it in a way that think is suitable to
ensure others don't make similar mistakes using your library.

        Your issue with the hidden pins on the tapped resistor, the pin
numbers obviously are defined as hidden. If they were not defined as hidden
you would not need to check the hidden pins checkbox in order to make them
visible. The checkbox may seem slightly confusing because the pin is
possibly not the portion of the information which is hidden, as you found
out the pin number can be hidden as well.

        As for being stupid or naive, no, I doubt that you are either.
Inexperienced, sounds more like it.


Brad Velander
Lead PCB Design
Norsat International Inc.
#100 - 4401 Still Creek Dr.,
Burnaby, B.C., Canada.
voice: (604) 292-9089 (direct line)
fax:    (604) 292-9010

-----Original Message-----
From: Kim Lester [mailto:[EMAIL PROTECTED]]
Sent: Saturday, February 24, 2001 8:15 PM
To: Multiple recipients of list proteledausers
Subject: RE: [PROTEL EDA USERS]: Library Management

Brian And everyone,

        I was just about to post a very similar message.
        I'm currently very irritated because I just found a library problem
in a 
production run of boards....
        Please let me know if I did something really stupid or if Prtoel did
stupid and
        I was too naive to catch it.
        The problem is:

                I made a schematic and converted it to a PCB.
                Gripe 1: There are no matching (default) PCB footprints for
the schematic
                        symbols. This stikes me as really dumb. There should
be a set...

                Gripe 2: The schematic symbol for a pot has pin 3 as the
                        I never saw this because my pin names were off...
                        I converted from sch to PCB and applied the generic
                        VRn - to avoid wiring problems (hah!). That what the
whole point of this
                        technology is for isn't it!


                Question:  Take the RETSISTOR TAPPED sch library part for
                        It does not have any hidden pins (according to
library params)
                        yet I have to use display hidden pins to see the pin
nums etc...
                        Why is this so ?

                Question:  What is the correct way of assiging schematic
pins so they
                        match PCB pins (how do I make the change and ensure

                Question: Do I have to create my own compatible sch and PCB
libs which
                                seems really stupid in as "professional" a
product as PCB.


                Ok so am I being really stupid/naive or is it a serious
problem ?


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