New to PCB design- Help?

Discussion in 'The Projects Forum' started by grldfischer, Jul 22, 2010.

  1. grldfischer

    Thread Starter New Member

    Jul 22, 2010
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    Hello All,

    I am brand new to PCB design and I came across this forum while browsing. It’s very interesting to meet members here who are sharing information on PCB designing. I came across few articles on web regarding DFM (Design for Manufacturability) methodology which helps designers incorporate manufacturing knowledge during the initial design process, preventing design errors early in the design process and reducing the need for costly corrections later. Also one of my friends suggested me that we have free DFM software’s offered by few PCB manufacturers which is of great help to PCB designers. Ever heard of DFM methodology? Thanks much!
     
  2. windoze killa

    AAC Fanatic!

    Feb 23, 2006
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    WOW..... they have now got a name for it.

    We have been doing it for years. One of the biggest DFM technologies is human. Engineers can design anything on the planet BUT thats where it ends in most cases. If you a design engineer and you what to make sure "DFM" is applied the give it to a technician for review. They will (in most cases) discover the shortcommings of a design.

    For example, are the mounting holes in the right place? Is there enough clearance around the holes? Have you left enough clearance for connectors? Is the orientation of the connectors correct to allow the mating half to mate?

    There are heaps of different aspects that must be considered.

    Just remember.... Engineers design things and technicians make it work. ;-)

    Nearly every design you see will have a REV higher than 1.
     
  3. JoeJester

    AAC Fanatic!

    Apr 26, 2005
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  4. grldfischer

    Thread Starter New Member

    Jul 22, 2010
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    Hey All,

    Thanks for your swift response. Can you please let me know if we have any free software available for DFM check?
     
  5. sage.radachowsky

    Member

    May 11, 2010
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    There's "design rules check" that comes with free software.... like KiCad, Eagle, PCB Artist, etc...

    You can include many rules that relate to manufacturability, like the size of annular rings, the size of vias, the spacing of traces from other traces, things like that. Some manufacturers will give an automated design rule check when you upload files, and they will flag additional problems.

    Maybe the line is blurred as to what is "design rule check" and "design for manufacturability" but there are plenty of things that cannot be checked with an automated system. Like how the parts will fit together physically, and how it will be assembled. Some things come only from experience and hard knocks.

    Here is a nice little essay by SparkFun.

    I would add that there is another thing called "design for testing" that is most useful for prototyping -- knowing where to place 0 Ohm resistors or jumpers for testing current on a connection, or test points for voltage, or ground points for clipping scope grounds, and making the silkscreen useful to save time in referring back to layout/schematic.
     
  6. grldfischer

    Thread Starter New Member

    Jul 22, 2010
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    Thank you so much for the detailed information. It was really helpful. Can you suggest me some manufacturers who has DFM check as complimentary service to customers.
     
  7. retched

    AAC Fanatic!

    Dec 5, 2009
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    Many companies do a DFM check when you send your order for PCBs in to be manufactured. They will call you to tell you it failed, but I have yet to find one that will fix it for free.
     
  8. grldfischer

    Thread Starter New Member

    Jul 22, 2010
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    Hey all,

    I did an extensive research on PCB suppliers who does DFM check as complimentary service to their customers and came across Sierra Circuits who does free DFM check for customers using an online tool called Better DFM. Few of my friends have tried the same and it worked great for them. For more information click http://www.protoexpress.com
     
  9. marshallf3

    Well-Known Member

    Jul 26, 2010
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    This is where I get my boards made and they offer free DFM with an output that's extremely easy to understand. Results are usually back within a half hour.

    http://www.4pcb.com/
     
  10. grldfischer

    Thread Starter New Member

    Jul 22, 2010
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    Hey Marshallf3,

    Thanks for the info. This time I have decided to place my PCB orders with Sierra Circuits. Let me give it a shot!
     
  11. mcgyvr

    AAC Fanatic!

    Oct 15, 2009
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    DFM= industries newest buzz word for "my PCB designer is an amateur."

    DFM is basically can this PCB be made at our fabrication shop.
     
  12. marshallf3

    Well-Known Member

    Jul 26, 2010
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    Amateur perhaps, and the better design programs will usually catch all the faults anyway but I've had a couple of cases where it's pointed out some areas that were easily improved.

    Generally I run the tests on my program with the default settings, then slowly tighten the tolerances until it starts showing potential problem areas. The way I see it the more leeway I've got in the tight areas the less likelihood of accidentally forming a solder bridge when assembling the circuit by hand.
     
  13. grldfischer

    Thread Starter New Member

    Jul 22, 2010
    6
    0
    Just noted that Sierra Circuits is exhibiting in the event conducted by "Antenna Systems 2010" on October 19th - 20th and 20% discount is given on PCB's. Sounds Interesting! For more information check https://www.protoexpress.com/ANTENNA
     
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