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 Measuring transient currents using Ocean 

Last post Fri, Oct 24 2008 9:41 AM by coco009. 3 replies.
Started by coco009 24 Oct 2008 08:45 AM. Topic has 3 replies.
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  • Fri, Oct 24 2008 8:45 AM

    • coco009
    • Top 500 Contributor
    • Joined on Thu, Oct 2 2008
    • Posts 17
    • Points 250
    Measuring transient currents using Ocean Reply

    Hi,

     

    I have a small issue that I hope somebody would be able to help me with.

     

    I am running transient sims on a current bias and sinking current through a 0V vdc cell. Using the ADE calculator, I can do the command: value( IT("/myVDC/PLUS") myTime). This gives me the value of the current at a specified time at the PLUS terminal of the VDC. Great, exactly what I want.

     

    However, if I do this command within an ocean script, it appears to fail, i.e., it returns a nil value and I dont know why? (I am saving the current at this node within the script). Furthermore, my ocean script is able to plot the transient current at this node with no problems.

    I dont understand why the same command from the calculator, value( IT("/myVDC/PLUS") myTime) does not work within ocean. Does anybody have any idea why this command would not work in Ocean or have any idea where the problem may arise?

     

     

    Thanks very much in advance!

     

    coco009
    • Post Points: 35

  • Fri, Oct 24 2008 9:23 AM

    • skillUser
    • Top 10 Contributor
    • Joined on Fri, Sep 19 2008
    • Austin, TX
    • Posts 2,426
    • Points 13,215
    Re: Measuring transient currents using Ocean Reply

     Hi,

     I would recommend using the "i" data access function, for example:


     selectResult('tran)
     value(i("/myVDC/PLUS") myTime)

    You may need to try with and without the leading "/".

    Regards,

    Lawrence.

    Filed under:
    • Post Points: 5

  • Fri, Oct 24 2008 9:28 AM

    • skillUser
    • Top 10 Contributor
    • Joined on Fri, Sep 19 2008
    • Austin, TX
    • Posts 2,426
    • Points 13,215
    Re: Measuring transient currents using Ocean Reply

     Also, consider using an "iprobe" device instead of a zero-voltage DC source, the latter will add to the complexity of the circuit and require additional equations to be solved, whereas the iprobe will not, so it is more efficient.

    Regards,

    Lawrence.

    • Post Points: 20

  • Fri, Oct 24 2008 9:41 AM

    • coco009
    • Top 500 Contributor
    • Joined on Thu, Oct 2 2008
    • Posts 17
    • Points 250
    Re: Measuring transient currents using Ocean Reply

    Hi Lawrence,

     

    Thanks very much for your prompt reply. I tried out what you suggested and it worked fine, so thanks for that. If I have time, I will try and understand what was going on there.

     

    I will also take on board your suggestion regarding the iprobe cell. I think that is a good idea.

     

    Thanks again!

     

    coco009
    • Post Points: 5
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Started by coco009 at 24 Oct 2008 08:45 AM. Topic has 3 replies.