Image Map Image Map
Page 5 of 5 FirstFirst 12345
Results 41 to 41 of 41

Thread: Open source WiFi RS232 Modem

  1. #41


    Quote Originally Posted by drdanj View Post
    Thanks Tim Those're really awesome bits of advice.
    No worries, glad to help!

    Quote Originally Posted by drdanj View Post
    Beefed up the power and tidied it up where I can - you can't really go any bigger than the pad that you're supplying the voltage to (or taking it from), but I tried to keep the trunks bigger where possible.
    Actually, you can! I don’t know if KiCad has implemented this yet, but most EDA tools will automatically neck down larger traces when they go into smaller pads. For example, if a pad is 20mils wide and I select a 40mil trace, it will start out at 15mils wide, then go up to 20, 25, 30, 35 and finally 40mils over the first 10mils of the trace. If KiCad doesn’t do this automatically you can still do it manually.

    Yes, the final pad size will still be smaller than the trace, but that’s OK. The point is to lower the overall impedance of the trace. (Remember, resistance is a function of Trace Width x Length.) A good example of this is the VIN and SW nets of U1 on my board. The pads of the IC are tiny, but I use hand shaped copper pours that quickly expand in size after they leave the pads to keep the impedance low.

    The trace width of the power net on the Gerbers you just posted should be OK, this is just some advice for future reference.

    Quote Originally Posted by drdanj View Post
    Also added lots more stitching between the layers. I did have a go at shrinking it, but if I want to keep everything on one side it did start getting rather too tight

    Anyway, I think this is better:

    Yes, that looks much better!
    Last edited by timb; Today at 05:20 PM.


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts