Translating a Schematic into a PCB using Traxmaker

Discussion in 'Homework Help' started by RyanKim, Sep 24, 2011.

  1. RyanKim

    Thread Starter Member

    Sep 18, 2011
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    Hi guys how are you? Im currently taking this manufacturing course where we have to build a powersupply, and currently I am in the stage of constructing a PCB using trax maker. Im having trouble translating the PCB from the Schematic I find myself questioning certain connections and being unable to make a connection due to certain restraints. If you could, I have attached a small image of the connection im referring to...

    Currently Capacitor 1 (C1) is attached to R1 with a track. and then R1 to C3 throught a track connected to U1 (which is a regulator in this case).

    My question is...there has to be a track going to U2 (also a regulator). If at N (Node1) I connect to U2 before R1...is that the same as moving N1 between R1 and C3 and then connecting it to U2?

    Srry if thats not so clear I've been working on this damn thing for so long I've had to erase and start over so many times at this point im just so frustrated.

    What makes this so difficult to is that there are constraints regarding board size, fixed regulators etc etc.
     
  2. justtrying

    Active Member

    Mar 9, 2011
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    Did you mean to move track to where I drew the blue line?

    - if you consider it carefully, you just changed the voltage level going into the regulator.

    I have worked with Traxmaker for a course, also a power supply. The key is figuring out the layout of your components. Check out where you regulators are with respect to each other and make sure that you have correct pin numbers, otherwise nothing will work in the end. Also, when laying tracks, start with the width that you need and not the narrow tracks otherwise overlap will happen when you have to make corrections. You will also probably will have to constantly fiddle with snap feature. In Traxmaker we were advised to do the ground last, the PCB was not designed for a ground plane.
     
    Last edited: Sep 24, 2011
  3. RyanKim

    Thread Starter Member

    Sep 18, 2011
    37
    1
    Ah thank you so much I did mean exactly what you were saying. And somewhere deep down a voice was telling me that I was infact changing the voltage level but my brain refused to listen. I actually resolved the issue, and yeah I have been watching the track widths and pad sizes etc. I managed to Snake a path before R1.
     
  4. RyanKim

    Thread Starter Member

    Sep 18, 2011
    37
    1
    Arghhh I realized I missed a connection and am still running into a similar problem...if i were to post the PCB file and appropriate schematic could someone possibly give me some advice? Its just that one connection is seemingly impossible at the moment while I have been able to make every other connection........perhaps even show me a better way to layout the components within my constraints?
     
  5. justtrying

    Active Member

    Mar 9, 2011
    329
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    if you post the schematic, maybe I could give you some advice. But really, with PCB design, you have to:
    - be patient and always refer back to schematic
    - play around with arranging components
    - if it does not work, start again

    What connection did you miss?
     
  6. RyanKim

    Thread Starter Member

    Sep 18, 2011
    37
    1
    Hi....yeah I know it takes patience and its definitely "put the hours in" kind of deal but I have put some pretty heavy hours into it. Im just pressed for time now and its frustrating to have to start over and over. I keep being denied one connection because there no longer seems to be a viable path to it.

    See how with U1 (regulator 7805) pin 1 I just cant get C3's positive pad connecting to C1 through R1 because im essentially cut off.....eveyrtime i think i have it i get cut off another path


    Oh also srry for the informal schematic....and I know some things are wrong in the PCB, thats because i've been trying to jostle stuff around so things have been put out of position.
     
    Last edited: Sep 25, 2011
  7. RyanKim

    Thread Starter Member

    Sep 18, 2011
    37
    1
    Ahh sorry for double posting continuously but my mind is everywhere. I have a zip of files because its probably crummy to look off a screenshot.

    Some of the constraints im under are

    R1 has to be 10mm away from any capacitor due to the heat it produces
    Track to track distance has to be 1.50mm, pad to pad also 1.50 mm and track to pad 1.50 mm. pads have to be 1.5mm away from components as well.
    U1-U3 (the regulators) have to aligned to one side and cannot be mirrored
    The X marks on the schematic are external connections to things such as potentiometer, an LED so on connected with jumpers.

    Also I can only have 1 track running between capacitor pads.

    3-5 mm clearance between component footprints
     
    Last edited: Sep 25, 2011
  8. justtrying

    Active Member

    Mar 9, 2011
    329
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    What you could try is flipping the resistor vertical - you need to move C1 and C5 slightly to the right to make it fit, but it would make the trace to R1 much shorter. Then I think you should be able to connect C1 to one side of the resistor on one side and C3 to the other - you might be looking at snaking your way in between the diodes.

    As a side note, 90 degree angles are undesirable on PCBs 45 is better because cracks form when angles are sharp.
     
  9. RyanKim

    Thread Starter Member

    Sep 18, 2011
    37
    1
    ahh well I guess I should have said the constraints earlier but I tried orienting R1 vertical but there just wasn't clearance of 10mm from any of the capacitors. Also C5 is actually C2 LoL. srry I should have said I mirrored some of them
     
  10. justtrying

    Active Member

    Mar 9, 2011
    329
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    yes, I see what you mean
     
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  11. RyanKim

    Thread Starter Member

    Sep 18, 2011
    37
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    Ive already deleted all my tracking once again and am trying to redo it...I guess I just gotta keep going...but it feels like with the constraints this is an impossibility but thanks for looking at it.
     
  12. justtrying

    Active Member

    Mar 9, 2011
    329
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    Hope this helps a bit... I am not redoing the entire circuit for you (drowning in my own homework) - I drew part of yours on Eagle PCB software, my TRAX is not working.

    Caution, pins on regulators are prob wrong, but you may notice that the traces do not have to go to the nodes as they are drawn on the schematic, as long as it flows into the same point somehow - look at how I connected R1 to C3 they share a node with 7805. Tricks like these help to figure it out eventually

    p.s. note that I did a bad job with traces - they do not follow any of my own advice...
     
    RyanKim likes this.
  13. RyanKim

    Thread Starter Member

    Sep 18, 2011
    37
    1
    Oh no I would never expect anyone to do it all....but thanks for working that out for me....
     
  14. justtrying

    Active Member

    Mar 9, 2011
    329
    353
    you can see traces better here...
     
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