Connect with us

Simple PCB program

Discussion in 'Electronic Basics' started by Ant_Magma, Mar 9, 2006.

Scroll to continue with content
  1. Ant_Magma

    Ant_Magma Guest

    Guys, i'm now trying to draw the PCB for my Ethernet system.

    It's just a simple single layer PCB. What's the simplest program out
    there you all would recommend that is easy to pick up and contains a
    good size component library?
     
  2. Noway2

    Noway2 Guest

    While not in answer to yor PCB tools question, your post had something
    that caught my attention. From what I understand about implementing
    ethernet (I am no experert, but I am working on a project that will do
    just that) I am questioning whether or not a "simple single layer PCB"
    will be adequte electrically for ethernet. Have you investigated the
    electrical requiremnets regarding the transmission lines as they run on
    the board? Do they require a particular differential impedance,
    relative to the +/-, etc?

    Note, a quick google search of the terms, PCB, ethernet,
    characteristic, and impedance pulled up a lot of application notes on
    interfacing to PHY devices which indicate that at a minimum a four
    layer board would be required and the transmission lines should be kept
    parallel, stubs should be avoided, and they should be designed for
    50Ohm impedance. It also specified information regarding proper
    decoupling and protection.
     
  3. Joel Kolstad

    Joel Kolstad Guest

    He doesn't say which speed of Ethernet he's after, but assuming 10Mbps, I'll
    mention that I've seen such designs work fine on two layer boards. Unless the
    OP is going to start mass manufacturing his product and selling it, I doubt
    the effort and expense of a 4 layer PCB is justified.
     
  4. Very basic and easy to use PCB Wizard 3, about $50.00.I tried a few free
    ones and found them to be way way more than I required. With PCB Wizard
    I was able to create the board in about 20 minutes. It's library had
    everything that I needed but again I am making boards with 10-25 parts
    on them.
     
  5. Guest

    if any question, please send mail us!!!!!!

    Sell high quality HDI PCB (CHINA)

    we send pcb by DHL or UPS ( Send to USA About 1 days from china)


    Product Name: Printed Circuit BoardPlace of Origin: ChinaFeatures:
    1) Surface finish: hot air solder leveling, entice, immersion gold,
    carbon ink, gold finger, peelable mask
    2) PCB file format: protel,powerpcb,Gerber file,Engle....
    3) Profile: routing, punching, V-Cut, chamfered
    4) Number of layers for mass production: 2 - 12
    5) Finished copper weight from .25 to 3oz
    6) Minimum finished hole size .006"
    7) Min. trace .004" - Min. space .004"
    8) Max. panel size: 18" x 24"
    9) Printed circuit board final thickness from .016" to .125"
    10)soldermask /Legend in a variety of colors
    (Green,White,Black,Yellow,Red..)
    11)operating costs (10 pieces ): 2 layers( about 0.048$/inch) 4
    layers(about 0.096$/inch)

    Lead times: 2 layers( 1 days, 3 days, 5 days) Ships next day.
    4 layers( 2 days, 5 days, 7 days)
    6 layers( 3 days, 5 days, 8 days)



    we send pcb by DHL or UPS ( Send to USA About 1 days from china)

    Min Qty 3pcs.

    Company Name: Nanjing Xilun Printed Circuit Board Co., Ltd.
    Contact Person: Mr. Ding JiaBao
    Leave me a message
    Address: 9 Changjiang Road, Nanjing City, JiangShu Province. China
    Zip: 210016
    Telephone: 86-025-8606 1148
    Fax: 86-025-8695 7829
    Website: http://www.njpcb.com
    E-mail:


    if any question,Please send e-mail to us,we will reply as soon.
     
  6. Ant_Magma

    Ant_Magma Guest

    Well, the reason i'm using Ethernet is because i'm sort of forced to.
    I'm using Belfuse's powerline module and this module use MII as its
    host interface
    http://belfuse.com/Data/DBObject/0804-5000-03-04.pdf

    This is an academic project.

    I understand building an Ethernet system involves alot of design
    parameters which with my current level of engineering knowledge might
    prove to be quite a challenge. Thus, i would really need any help i can
    get. This discussion group and you guys is one of them.

    How about just a single layer? Assuming the size of the PCB is not
    limited?
     
  7. Ant_Magma

    Ant_Magma Guest

    Well, the reason i'm using Ethernet is because i'm sort of forced to.
    I'm using Belfuse's powerline module and this module use MII as its
    host interface
    http://belfuse.com/Data/DBObject/0804-5000-03-04.pdf

    This is an academic project.

    I understand building an Ethernet system involves alot of design
    parameters which with my current level of engineering knowledge might
    prove to be quite a challenge. Thus, i would really need any help i can
    get. This discussion group and you guys is one of them.

    How about just single layer? Assuming the size of the PCB is not
    limited?

    Now what i can only do is follow the reference design and fabricate the
    PCB (since testing on a breadboard is not possible) and cross my
    fingers.
     
  8. Search for express pcb. easy to use and can print double layer designs.
    Jim.
     
  9. JeffM

    JeffM Guest

  10. Noway2

    Noway2 Guest

    Do you mean that this is for school? If so, I think you may have
    bitten off more than most students can chew.
    If you are carefull, can read and comprehend reference desings and
    datasheets, and have sufficient proficieny with your PCB tools you may
    be able to handle it.
    As one of the previous posters said, they have seen lower bandwidth
    ethernet implemented on less than four layers, though I wouldn't be
    inclined to try it. There are a couple of problems with boards less
    than four layers. First, the addition of a power and ground plane
    provide a natural source of bypass capacitance to your power system.
    Typically, though this capacitance doesn't come into play until you hit
    fairly high frequencies. What this means is that a lot of applications
    you can get away with a two layer board. The second problem is that in
    order to have a stable power supply system you need to have a low
    impedance ground path. Note the word impedance as this also includes
    inductance. To get a low impedance path you need to have a solid
    ground plane. Even a plane full of holes is infinitely better than
    serpentine traces. On a two layer board you can implement a copper
    pour as a ground plane. If you are using PTH components, you should
    consider putting the pour on the top so that you don't warp the board
    with a wave solder. Thid, you need to be judicious in your use of
    bypass capacitors. You are best off with a low inductance package such
    as a chip components as opposed to through hole. They need to be close
    to the power pins (less than .25") and need to be of a proper type.
    Aluminum Electrolytics are ghastly in this type of application.
    Ceramic are a much better choice, with .1 to .01 being typical values
    per rule of thumb.

    Implemented properly you can meet the requirements of having a stable
    power reference (low impedance power and ground over the freq band of
    interest), even on a two layer board. A single sided, single layer
    board can't.

    The other problem you may run into with ethernet is that the data lines
    requie a certain characteristic impedance and are matched in impedance.
    This means you need to be carefull in your layout to keep the traces
    the same length. The characteristic impedance, is determined by
    geometry; trace width, thickness, and distance from reference (plane).
    Without a reference (ground) plane you can't get a deterministic
    impedance as you will have no idea where the high freq return currents
    will flow (it may not be along the copper).
    There will be some finger crossing involved. If you are confident that
    you have done everything to the best of your ability, followed proper
    guidelines, etc there shouldn't be too much risk. Like I said though,
    trying to do this on a single layer board, I doubt if it will work.
    Two layer, single sided your chances go up. Four or six layer board,
    per recommendations of the IC manufacturers you start getting pretty
    good odds.
     
  11. hmm, that jim thompson is not me. but the subject was "simple pcb program"
    and it is simple and free. I have used it to draw up 2 layer boards, print
    each layer out, scan into photoshop to edit slightly , and print to toner
    transfer paper to make my pcb's. So it will do "simple" boards.
    What I would like to find is a pen plotter with flatbed and load it with
    laqcuer ink to draw on the copper clad directly.. Know of any cheap
    plotters out there?

    Jim..
     
  12. David Harmon

    David Harmon Guest

    On 9 Mar 2006 07:24:43 -0800 in sci.electronics.basics, "Ant_Magma"
    PCB design software is in the CAD (computer aided design) category,
    so this question should be on sci.electronics.cad
    When you get there look for Terry Pinnell's encyclopedic review of
    what's available. http://www.terrypin.dial.pipex.com/ECADList.html

    Never get your PCB software from the company that wants to sell you
    boards. It's a scam to get you to design the board using their
    "free" software... then when you are done you find out that they are
    the only place that will make boards for you. Get your software
    from a software company so you can shop around for the boards.

    I like Eagle from www.cadsoft.de the free demo version is plenty to
    get started with. But it may not be as simple as you hoped.
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-