Shop OBEX P1 Docs P2 Docs Learn Events
wiki page for pcb design — Parallax Forums

wiki page for pcb design

mparkmpark Posts: 1,305
edited 2009-10-31 03:29 in Propeller 1
A lot of folks are designing their own Propeller PCBs, and I hope to do so too. In preparation for that eventuality, I have started a page on the wiki to collect relevant information from the forum.


The page, very crude (I just started, remember), is here: http://propeller.wikispaces.com/pcbdesign



Take a look, and if you have any suggestions, tips, or links you'd like to add, please pm/email me, post here, or edit the wiki yourself.

[noparse][[/noparse]edit: rephrased infelicitous wording]

Post Edited (mpark) : 10/31/2009 3:34:30 AM GMT

Comments

  • mctriviamctrivia Posts: 3,772
    edited 2009-10-28 23:14
    other reasons not to use 90 angles is traces get narrowed at corners and they increase reflections in high frequency traces.

    0603 resisters are very easy to work with by hand and there smaller size makes for easier placement.

    I would recomend if people have room have an sd card and 512kbit eeprom for comercial products. if you do then you can use my bootloader to install updates.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    24 bit LCD Breakout Board coming soon. $21.99 has backlight driver and touch sensitive decoder.
  • hover1hover1 Posts: 1,929
    edited 2009-10-28 23:28
    Micheal, Great stuff. Thanks for the work on putting this together.

    Jim
    mpark said...
    A lot of folks are designing their own Propeller PCBs, and I hope to become one of them. In preparation for that eventuality, I have started a page on the wiki to collect relevant information from the forum.

    The page, very crude (I just started, remember), is here: http://propeller.wikispaces.com/pcbdesign

    Take a look, and if you have any suggestions, tips, or links you'd like to add, please pm/email me, post here, or edit the wiki yourself.

  • Dr_AculaDr_Acula Posts: 5,484
    edited 2009-10-29 00:03
    What a great little website!

    I wrote up an Instructable on how to make PCBs www.instructables.com/id/Professional-PCBs-almost-cheaper-than-making-them-/ If this is helpful maybe you could include a link?

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    www.smarthome.viviti.com/build
  • SRLMSRLM Posts: 5,045
    edited 2009-10-29 00:19
    You might want to include some common numbers like demo board pinouts, protoboard overall size, dip pin spacing, etc.
  • JamesxJamesx Posts: 132
    edited 2009-10-29 01:15
    How about suggestions or examples of common fabrication shops (for boards)? There have been several threads on this topic through the years, but it's hard to remember everything...

    Jim
  • CenlasoftCenlasoft Posts: 265
    edited 2009-10-29 02:17
    Hi MPark,
    Great site. I will post a new version of my PCB with my EDDY CURRENT ANALYZER in a few days. I am now using the 2 channel 12 bit ADC with it. I am etching it tomorrow. I also use the Processing language to image my results (processing.org).
    Thanks,
    Curtis
  • jazzedjazzed Posts: 11,803
    edited 2009-10-29 05:05
    Nice wiki page.
  • AleAle Posts: 2,363
    edited 2009-10-29 06:36
    mpark:

    0603 parts are tiny, I think that unless space is a constraint 0805 or 1206 are ok. Just making them smaller may not always be advantageous.

    Units: Parts come in imperial and metric sizes, sadly. When you give size it would be useful to have both for example: 50 mils (1.27mm), or 1.27 mm (0.05"). Or something similar.

    Photoboards: They really need testing. Exposure time varies from manufacturer to manufacturer (and with the kind of paper or transparency you have), and developing too.

    So far I like it. Well done.

    Edit: name corrected.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Visit some of my articles at Propeller Wiki:
    MATH on the propeller propeller.wikispaces.com/MATH
    pPropQL: propeller.wikispaces.com/pPropQL
    pPropQL020: propeller.wikispaces.com/pPropQL020
    OMU for the pPropQL/020 propeller.wikispaces.com/OMU

    Post Edited (Ale) : 10/29/2009 10:47:39 AM GMT
  • mparkmpark Posts: 1,305
    edited 2009-10-29 06:39
    Thanks for the encouragement and suggestions. I'll slowly flesh it out (for example, one of the links there is to a thread with a lot of fab shops; I plan to collect the names out of the thread and put them on the page itself).

    Keep the suggestions coming.
  • SeariderSearider Posts: 290
    edited 2009-10-29 18:09
    Here are a couple of recent threads with some usefull information

    http://forums.parallax.com/showthread.php?p=851730

    http://forums.parallax.com/showpost.php?p=0



    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔

    Searider
  • hover1hover1 Posts: 1,929
    edited 2009-10-29 18:28
    How about links to PCB Design software?

    Eagle
    ·http://www.cadsoft.de
    Diptrace
    ·http://www.diptrace.com
    Express PCB
    ·http://www.expresspcb.com
    FreePCB
    ·http://www.freepcb.com
    PCB123
    ·http://www.pcb123.com
    Advanced Circuits
    ·http://www.4pcb.com

    Jim
  • SapiehaSapieha Posts: 2,964
    edited 2009-10-29 18:31
    Hi mpark.

    You have some bud words in You Text on Bypass/Decouplings Capasitors.

    Look att part ---- xxx ---- NEVER increase any Decoupling CAP. BUT possibly use one to in parallel with diferent value.
    Decouplings Caps work as filters for transcient frequencies and value of them is important to met that frequencies.
    BUT sometimes it is need for 2 and more diferent values in Parallel to CUT diferent frequencies that can go out from and go from outside to Propeller Suply Rails.

    To that ADD one or more big Tantalum (10uF and more) that can suply Propeller with more CURENT in momentary curent intensive work.

    "Bypass/decoupling caps

    •You need one 0.1uF ceramic bypass cap next to each Vdd/Vss pair. For the Prop chip itself,
    it wouldn't hurt to increase this to 0.22uF or 0.47uF.

    •decoupling caps on the prop. If you plan to socket the Propeller, you can fit them under the propeller, that lets you get them really close to the power supply pins. I'd do one for each side. 0.1 uf or so. I've found that Machine pin 40 pin dip sockets give you the room, the cheap sockets put a reinforcement rib right across the center, blocking the area I normally put them. My point? look at the socket you plan to use before laying out the board, or you may find problems when you decide to solder them together.
    •about decoupling caps ... put down some 1208 or 806 smd device pads with short fat traces. There is nothing on the back so a ground plane would be nice there and will make the fab easier to spin. If it was my board I would allow a provision for putting smd resistors in series with all propeller traces"

    Regards

    ChJ

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Nothing is impossible, there are only different degrees of difficulty.
    For every stupid question there is at least one intelligent answer.
    Don't guess - ask instead.
    If you don't ask you won't know.
    If your gonna construct something, make it·as simple as·possible yet as versatile as posible.


    Sapieha
  • mparkmpark Posts: 1,305
    edited 2009-10-30 07:42
    Thanks fellows, more good stuff.

    Sapieha, I believe you started a thread on overclocking the Propeller which included lots of information about decoupling caps. Do you have a link?
  • DroneDrone Posts: 433
    edited 2009-10-30 10:42
    @mpark,

    Thanks for starting the Wiki page - nice idea.

    1. You forgot to mention the best (IMHO), free (GPL), cross platform (MAC too) suite of programs for EDA (Electronic Design Automation), KiCAD. KiCAD has Schematic capture, PCB layout editor, Gerber viewer, footprint selector, footprint editor. autorouter, project manager, etc.; a complete suite capable of producing professional quality layouts..

    iut-tice.ujf-grenoble.fr/kicad/

    kicad.sourceforge.net/wiki/index.php/Main_Page

    There's a large (2,5k member) active KiCad Yahoo Group here:

    tech.groups.yahoo.com/group/kicad-users/


    2. There is an excellent Homebrew PCB Yahoo Group with almost 5k members. Much help on EDA and fabricating your own PCBs:

    tech.groups.yahoo.com/group/Homebrew_PCBs/


    3. I often use Futurlec for contract PCB fabrication. They have an automated quote generator on-line. Reasonable prices, fast turn-around, low cost World wide shipping available.

    www.futurlec.com/PCBService.shtml

    4. SeeedSstudio in China has a nice PCB service and can even partner with the designer to distribute an open hardware "product" through their online store. Low cost International shipping with tracking via Hong Kong.

    www.seeedstudio.com

    5. I don't think it is Nuts and Volts that's directly affiliated with Batch PCB, I think it is www.sparkfun.com. If you have a lot of boards that add up to one or more panels, then Batch PCB can turn around fairly fast. I believe Batch PCB uses Gold Phoenex for the actual fab.

    Regards, David
  • Cluso99Cluso99 Posts: 18,069
    edited 2009-10-30 11:34
    Design rules for stable propeller operation and overclocking http://forums.parallax.com/forums/default.aspx?f=25&m=356308

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Links to other interesting threads:

    · Home of the MultiBladeProps: TriBlade,·RamBlade,·SixBlade, website
    · Single Board Computer:·3 Propeller ICs·and a·TriBladeProp board (ZiCog Z80 Emulator)
    · Prop Tools under Development or Completed (Index)
    · Emulators: CPUs Z80 etc; Micros Altair etc;· Terminals·VT100 etc; (Index) ZiCog (Z80) , MoCog (6809)
    · Search the Propeller forums·(uses advanced Google search)
    My cruising website is: ·www.bluemagic.biz·· MultiBladeProp is: www.bluemagic.biz/cluso.htm
  • mctriviamctrivia Posts: 3,772
    edited 2009-10-30 13:18
    It has been shown using different value decupling caps actually worsens emi.

    It is recommended to compute value needed and in addition to placing by vdd pins to also spread out over board where signals change layers

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    24 bit LCD Breakout Board coming soon. $21.99 has backlight driver and touch sensitive decoder.
  • mparkmpark Posts: 1,305
    edited 2009-10-31 03:29
    Thanks again.
Sign In or Register to comment.