Page 2 of 2 FirstFirst 12
Results 11 to 17 of 17

Thread: PCB design best practices & critique (RFC)

  1. #11
    Join Date
    Dec 2010
    Location
    SF Bay Area
    Posts
    683
    Post Thanks / Like

    Default Re: PCB design best practices & critique (RFC)

    I was thinking I might use solder paste. Probably not with a stencil since this is a prototype (that might not work) and I'm making only one. Just using a syringe/dispenser and covering multiple pads and a soldering iron with a fine point (as you recommended above).

    Is it easier to use thin solder and the "tack one corner first, then other side, then all pins" method with a soldering iron, rather than just placing solder paste and then reflowing with an iron?

  2. #12
    Join Date
    Dec 2008
    Location
    Olathe, KS
    Posts
    127
    Post Thanks / Like

    Default Re: PCB design best practices & critique (RFC)

    Quote Originally Posted by ags0000 View Post
    I was thinking I might use solder paste. Probably not with a stencil since this is a prototype (that might not work) and I'm making only one. Just using a syringe/dispenser and covering multiple pads and a soldering iron with a fine point (as you recommended above).

    Is it easier to use thin solder and the "tack one corner first, then other side, then all pins" method with a soldering iron, rather than just placing solder paste and then reflowing with an iron?
    I would say it likely depends on the size of the board and number of components. For this board, I think the method you described with thin solder will work well. Also liquid flux can be your friend.

  3. #13
    Join Date
    Nov 2013
    Posts
    70
    Post Thanks / Like

    Default Re: PCB design best practices & critique (RFC)

    0605 is not unreasonable, the annoyance is that a while ago they stopped printing values on 0605 under the guise of environmental concerns, another reason to throw away any you drop.( If you have ones with markings be glad it is old stock).

    Everyone will work up their own technique, I tin one pad and push or hold the part with high quality curved tweezers ( cheap ones don't work) , curved allows me to rest my wrist on the bench for stability.

    We use a guy that happily hand builds prototypes down to 0201- and he is over 70.

  4. #14
    Join Date
    Dec 2010
    Location
    SF Bay Area
    Posts
    683
    Post Thanks / Like

    Default Re: PCB design best practices & critique (RFC)

    I need that! :-) vvvvvvvvvvvv

    We use a guy that happily hand builds prototypes down to 0201- and he is over 70
    Last edited by ags0000; 03-10-2018 at 02:24 PM.

  5. #15
    Join Date
    May 2007
    Posts
    5,323
    Post Thanks / Like

    Default Re: PCB design best practices & critique (RFC)

    I'm a bit late to the game, but what do the various layers represent? In particular, which layer(s) have the ground pour on them? I'm assuming both Test-B.Cu.pdf and Test-F.Cu.pdf have ground pour on them.

    Also, take a close look at the ground connections of the bottom three of the 20-pin chips. They do not appear to be connected to anything. Unless you've fixed that on later revisions of the board that might be the cause of the problems that you've been discussing in the signal integrity thread.
    Last edited by P. Short; 04-22-2018 at 05:42 PM. Reason: minor grammatical error
    Phil

  6. #16
    Join Date
    Nov 2013
    Posts
    70
    Post Thanks / Like

    Default Re: PCB design best practices & critique (RFC)

    As 6mil seems to be the limits of many vendors I would only get that thin where I had to, seems like you have plenty of space on most of the board.

  7. #17
    Join Date
    Dec 2010
    Location
    SF Bay Area
    Posts
    683
    Post Thanks / Like

    Default Re: PCB design best practices & critique (RFC)

    @P.Short Yes, front and back copper pour are ground. While it's not shown very well, the ground pins are directly tied to the copper pour (through thermal relief). Those .PDF files I had to upload are (for me) almost useless. Can't really see what's going on. If anyone knows the magic to make KiCad print out what I'm viewing in pcbnew I'd appreciate the tip. Screenshots are the next best thing I can think of.

Page 2 of 2 FirstFirst 12

Bookmarks

Posting Permissions

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