Stats

  • Locked Locked
  • Replies 4
  • Subscribers 164
  • Views 15246
  • Members are here 0
More Content
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Drill size and annular ring size of a PTH pad

C Shiva

 Hello everone,

 What is standard method of drill and annular ring size of a PTH pin? In other words, how much dimension we have to add to a PTH pin to define a drill and annular ring size? According to one source we have to add 10 mils to the pin size to define drill size and have to add 25 mils to the drill size to define annular ring. Is it correct? Any reply will be appreciated.

Thanks,

Shiva.

Parents
  • oldmouldy

    There may well be a standard but it is probably best to talk to your fabricator on this.

    The PCB tool is going to be specifying the finshed hole size, the fabricator will be using a larger drill than this to account for plating and machine tolerance, that will have an impact on how large the pad needs to be to remain attached to the board and still a complete shape, that is, not drilled through the edge.

    Many fabricators who offer a prototype service will post their "no adder" rules on their web sites, these might be a good starting point if you don't have a specific fabricator in mind.

    Within reason, larger is always better.

Reply
  • oldmouldy

    There may well be a standard but it is probably best to talk to your fabricator on this.

    The PCB tool is going to be specifying the finshed hole size, the fabricator will be using a larger drill than this to account for plating and machine tolerance, that will have an impact on how large the pad needs to be to remain attached to the board and still a complete shape, that is, not drilled through the edge.

    Many fabricators who offer a prototype service will post their "no adder" rules on their web sites, these might be a good starting point if you don't have a specific fabricator in mind.

    Within reason, larger is always better.

Children
No Data
Cadence Guidelines

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.