Home > Community > Forums > PCB Design > IPC-7351 Level C

Email

* Required Fields

Recipients email * (separate multiple addresses with commas)

Your name *

Your email *

Message *

Contact Us

* Required Fields
First Name *

Last Name *

Email *

Company / Institution *

Comments: *

 IPC-7351 Level C 

Last post Wed, Dec 26 2012 9:03 PM by C Shiva. 3 replies.
Started by C Shiva 26 Dec 2012 01:59 AM. Topic has 3 replies and 1001 views
Page 1 of 1 (4 items)
Sort Posts:
  • Wed, Dec 26 2012 1:59 AM

    • C Shiva
    • Top 50 Contributor
    • Joined on Tue, Jul 15 2008
    • Bangalore, Karnataka
    • Posts 164
    • Points 3,435
    IPC-7351 Level C Reply

    Hi all,

    Has anyone experienced on using of IPC-7351 level C footprints? Presently I'm using it in one of our project which is a very dense and space constraint board. My concern is,

    1. Is there anything issues we have to take a special care, as to avoid any DFA/DFM?
    2. What is the minimum space we have to keep for two level C footprints (major's and passive's) to avoid any assembly and manufacturing issues?

    Any input will be appreciated.

    Thanks,

    Shiva.

    • Post Points: 35
  • Wed, Dec 26 2012 1:22 PM

    Re: IPC-7351 Level C Reply

    SMT machines(particularly Fuji) have been able to place anything we come up with for the past 20 years.  Solder bridging and being able to rework a single part without affecting other parts have been factors.

    You need to get project management involved with assembly engineering. 

    A dumb test board to find out assembly issues in your factory might pay off if you are working on a high-volume design.

    Assembly will want a low-risk/easy board to build.  But, marketing is going to push beyond that.

    Have fun.

    • Post Points: 5
  • Wed, Dec 26 2012 2:01 PM

    • redwire
    • Top 10 Contributor
    • Joined on Thu, Jul 17 2008
    • Allen, TX
    • Posts 872
    • Points 13,450
    Re: IPC-7351 Level C Reply

     My experience has been similar to what Robert posted above.  We place at minimum feature separation (3 to 5 mils) and the boards are fine.  Yes, the assembly houses, especially the poor ones, will cry and complain but the good ones build with no issue.  Rework as he says can be problematic but that is a trade-off necessary to acheive the part density that we are at.

    • Post Points: 20
  • Wed, Dec 26 2012 9:03 PM

    • C Shiva
    • Top 50 Contributor
    • Joined on Tue, Jul 15 2008
    • Bangalore, Karnataka
    • Posts 164
    • Points 3,435
    Re: IPC-7351 Level C Reply

     Thanks all for your kind reply. It will be really helpfull.

    • Post Points: 5
Page 1 of 1 (4 items)
Sort Posts:
Started by C Shiva at 26 Dec 2012 01:59 AM. Topic has 3 replies.