KiCad problem

Discussion in 'General Electronics Chat' started by rsfoto, May 21, 2013.

  1. rsfoto

    Thread Starter Member

    May 14, 2013
    134
    1
    Hi,

    I am trying to place a mosfet 3D shape onto my board but have not yet found out how to orient the 3D shape so it fits into the 3 holes.

    Also in order to place the same circuit more times into a board (4x) how can I copy it in the PCB program or do I have to do it in the EeSchema.

    I want to have a BORN6 connector with a common power supply ground and so 4 separated + power supply connectors for switching 4 USB cables independently.

    Thanks for any tips
     
  2. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    7,386
    1,605
    I dunno, I never used the Kicad 3D stuff. I do layouts in 2D Autocad.

    Right click the entire circuit, when Block Operation window pops up select *everything* and drag to new spot. When you release the mouse button select copy... and there you go.

    You don't have much control over where it gets dropped, so choose your grid wisely.

    However... unless this is a home etch discount houses charge more for "sneaking in" copies. Premium houses will do the step & repeat for free (since you're overpaying anyway).

    You have my permission to do this. :confused:
     
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  3. rsfoto

    Thread Starter Member

    May 14, 2013
    134
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    Yes, I see now that was confusing as I started a new line :) This belonged to the sentence before.

    By The way I managed to make a board with 4 In- and Outputs using a 4 channel optocoupler as well as only 6 connectors for common ground and individual switching :D

    Will post the images as soon as I can. This is real fun
     
  4. panic mode

    Senior Member

    Oct 10, 2011
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    I use KiCad and make my own parts and 3D models all the time - it's fun.
    if you have the 3D model, use 3D properties to change offset and orientation. every time you change it, hit refresh on 3D model viewer. once everything is fine, you can use that component in PCB. if it already used, you can refresh it, just right click on component on PCB and select Edit Parameters, click on Change Modules and select "Change Same Module" to refresh all components of that type. if you have part number and link to datasheet, i could make you one that fits like a glove.
     
  5. rsfoto

    Thread Starter Member

    May 14, 2013
    134
    1

    Thanks for the explanation. Will try it as soon as I can.
     
  6. rsfoto

    Thread Starter Member

    May 14, 2013
    134
    1
    Again thanks. Well I think I managed to make made my component for the TLP521 optocoupler.

    Look at the attached image ending with ...1

    Also placing the component into the schematic circuit looked like it worked. Look at the image ending with ...2

    ... but when making the PCB the connector are mirrored upside down when I look at my physical TLP 521 I have on my desk eg. the Anode is on the left upper corner and in my PCB it is on the left lower corner. Looking at the 3D drawing the TLP 521 is on the correct place ¿?

    By the way I associated the existing footprint of the Optotransistor NsL32. Could that be the problem and if yes how can I correct that ?

    Any tip what is wrong here ?

    Is there a way to make footprints ?
     
    Last edited: May 25, 2013
  7. rsfoto

    Thread Starter Member

    May 14, 2013
    134
    1
    OK. A few minutes later and I solved my problem using the module editor in the PCBnew window.

    At least I hope it is correct :D

    Look at the attached image and it does match my prototype board I made yesterday.
     
  8. kubeek

    AAC Fanatic!

    Sep 20, 2005
    4,669
    804
    You should mirror the transistor to get it on the other side of the board. See, the transistor is on the top and the traces are on the bottom. That is why you still got that ratsnest wire going to the tab.
     
  9. rsfoto

    Thread Starter Member

    May 14, 2013
    134
    1
    I modified the footprint of the mosfet and now it looks like this. I made through holes for connecting the mosfet :confused:

    I still get confused how to choose the different connections mode when mking a new footprint. The connector numbers do now match the GDS of the APM 3095P.

    Is this possible ?
     
    Last edited: May 25, 2013
  10. kubeek

    AAC Fanatic!

    Sep 20, 2005
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    Why did you change it like that? All you needed was to move the part in the pcb from top to bottom.
     
  11. rsfoto

    Thread Starter Member

    May 14, 2013
    134
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    Because I do not want to have on two sides electronic components :)

    Can I do it like that or will I encounter soldering problems. I mean manual soldering.
     
  12. kubeek

    AAC Fanatic!

    Sep 20, 2005
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    What is the problem with having the transistor from the bottom and the through hole components from the top? It is prefectly standard practice.
    The way you have it now will be very hard to solder, because you´d need to somehow get a piece of wire soldered through the hole and to the pad on the far side.
    I suppose you want a single sided board without plated through holes as it is chepest.
    Also if you put the transistor from the other side there will be no overlapping wires (the two wires joining the shield pins on the opposite sides are redundant).
     
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  13. kubeek

    AAC Fanatic!

    Sep 20, 2005
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    Also you swapped drain and source on that mosfet between the revisions, so you´d better decide which is which.
     
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  14. rsfoto

    Thread Starter Member

    May 14, 2013
    134
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    Thanks. I understand what you say. I want to put some isolation mterial underneath and then a copper mesh and keep it as flat as possible on the side underneath.

    No, that is not a reason for me :D . There is no big difference ~ 10%.
     
  15. rsfoto

    Thread Starter Member

    May 14, 2013
    134
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    Yes that is true and I have checked it with the data sheet. Thanks
     
  16. panic mode

    Senior Member

    Oct 10, 2011
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    you may want to beef up those traces, are you sure they will handle the current?
     
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  17. rsfoto

    Thread Starter Member

    May 14, 2013
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    Thanks. We are talking of 500mA which is the current a USB port can supply.

    Will try to see how to do that.
     
  18. panic mode

    Senior Member

    Oct 10, 2011
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    then that will be enough, only need 8 mil...

    but if you want to change it, go to PCBNew menu 'Design Rules' and specify track width for given class of nets.

    by default there is only one and it is called 'default'. you can add more (signals, power, power_high_current, whatever) and assign nets to each of the classes.

    for example Vcc, GND etc can be 'power', rest is 'default'. then for power you specify track width of maybe 25-60mil. when you route board, PCBNew will then use whatever width was assigned to that net.
     
  19. rsfoto

    Thread Starter Member

    May 14, 2013
    134
    1
    Thanks, found it
     
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