Hi,

I think you are going to be disappointed.  In simple terms there is no such
thing as a 'standard' component
footprint.  Several factors define the footprint used for any single
component.

Potentially there are an infinite number of PCB footprints, I don't think
anybody has hade time to make
them yet.

Its best to collect a library of footprints that you know are correct for
your purposes.  Build on that over time.

Look at the manufacturers data for each component and see what they
recommend for the PCB assembly process that you are using, verify that your
footprint matches that data and that's its pins match the component symbol
in the schematic, record the results of each check. Doing this methodically
is much better than relying on someone else to get it right.

There are 'rules of thumb' generated mainly by experience and
experimentation, but they are only guides.  For instance two 0.5mm pitch
components with the same lead size may require different pad sizes depending
on their thermal mass, this is usually only found through trial and error.

Try the IPC website - can't remember the address, though a search engine
should find it.  They have a useful online calculator for land patterns.

I expect someone on this group will offer you some footprints that may meet
your needs, though check their work carefully against manufactures data.

Jason.

-----Original Message-----
From: Blandford, Simon [BSS Audio UK] [mailto:[EMAIL PROTECTED]]
Sent: 20 December 2001 09:26
To: 'Protel EDA Mailing List'
Subject: [PEDA] 1206 4xresistor network footprint in downloaded
libraries. Where?


Hi,

Does anyone know which library the footprint for a 1206 size 4x resistor
network is in and what it is called. I have downloaded just about every
Protel library I can find, done text searches in the library spreadsheet for
keywords "network, "array" and "resistor" and still can't for the life of me
find it.

We want to avoid making custom footprints if we can and go with "standard"
footprints as much as possible.

Regards,
Simon B.


The comments expressed in this email are my own and not necessarily those of
my employer. 

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