Stats

  • Locked Locked
  • Replies 5
  • Subscribers 164
  • Views 14156
  • 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

connecting to odd shape pad

cqfm

I am trying to connect to the ground pin on the Rosenberger 19S101-40ML5 SMO connector shown in the image. I have created the footprint using shape symbols. Now, the center of the GND pin is not metalized. I want to connect the GND VIA to one edge (top edge here) of the GND pin. How do i do that? I can recenter the shape symbol so that the center falls at the center of the metalized portion on the top edge, but then if i want to connect to the left or right edges in another instance i have to recreate the symbol with a different shape symbol (center of the pin moved again), i guess. Is there a straight forward way to do this in OrCAD, so that i can just snap to any metalized part of a pin?

Parents
  • Wild

    We use the same part in High Frequency ATE boards.  The outer pin should be a full pad connect, note the copper voids for thermal relief and the pin origin must be within the copper shape of the outer pin.   The center area must be free of copper, or you will get unwanted parasitic capacitance to the signal pin.  The route from the pin is a co planar controlled impedance.  Good luck.

    BTW the impedance in this case is 90 Ohm - my bad, I just double checked the impedance.  RFinley is correct, 50Ohm.

Reply
  • Wild

    We use the same part in High Frequency ATE boards.  The outer pin should be a full pad connect, note the copper voids for thermal relief and the pin origin must be within the copper shape of the outer pin.   The center area must be free of copper, or you will get unwanted parasitic capacitance to the signal pin.  The route from the pin is a co planar controlled impedance.  Good luck.

    BTW the impedance in this case is 90 Ohm - my bad, I just double checked the impedance.  RFinley is correct, 50Ohm.

Children
  • RFinley
    in reply to Wild

    Radio is mostly 50 ohms.  Risky assumptions.   My impression is high-speed digital is around 100 ohms.

    Kudos on coplanar waveguide.  We usually pull ground away and do microstrip.

  • cqfm
    in reply to Wild

    thank you for the info, and the bonus tips. Our application is low frequency (30 MHz) and uses lumped element matching, we do not need coplanar waveguides or microstrips, the traces are very short compared to the wavelength at 30 MHz.

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.