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Plated thru hole diamter

Discussion in 'Circuit Simulation & PCB Design' started by Mosaic, May 1, 2017.

  1. Mosaic

    Mosaic Well-Known Member

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    Hi:
    For a part that has an actual diameter lead of 1.2mm.
    What size should the PTH be? How much tolerance to add?
    I was thinking 1.25mm but then would the plating impact on this?
     
  2. Cicero

    Cicero Active Member

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    edit - DerStrom8's answer below much better
     
    Last edited: May 2, 2017
  3. DerStrom8

    DerStrom8 Super Moderator Most Helpful Member

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    IPC-2222 covers this.

    upload_2017-5-2_6-49-38.png
    upload_2017-5-2_6-52-55.png
     
  4. dave

    Dave New Member

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  5. Pommie

    Pommie Well-Known Member Most Helpful Member

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    Those seem like huge tolerances in today's age. Most boards I've had made seem to be spot on. 0.7mm over is huge - most of the time my holes are less them 1mm and often less than 0.7mm.

    Edit, just pointing out that I think that spec has been overtaken by modern methods.

    Mike.
     
  6. Cicero

    Cicero Active Member

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    DerStrom8 could you elaborate on what Level A-C are?
     
  7. DerStrom8

    DerStrom8 Super Moderator Most Helpful Member

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    From IPC-2221:
    Simply put, Level A is highest possible quality (medical equipment, aerospace, etc) that is more difficult to produce, Level B is moderate quality (consumer products, etc) which is standard producibility, and Level C is the easiest to produce but with lower quality (hobby projects, etc).
     
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  8. Mosaic

    Mosaic Well-Known Member

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    I guess I'll go with 1.3mm holes for 1.2mm leads. I've tried 1.5mm but mechanical integrity is a bit questionable as these are spade terminals.
     

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