IR2117 implementation - simulation trouble

Discussion in 'The Projects Forum' started by HMartins, May 10, 2011.

  1. HMartins

    Thread Starter New Member

    May 10, 2011
    21
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    Hi.

    I can't figure why I am in trouble to implement IR2117. It just seems not to work no mater how simple the implementation is. I have done the simplest I could imagine, still, doesn't work. Of course it all started with bootstrap capacitor, etc, then I decided to isolate just this bit of as simple as possible circuit.

    In the files:
    http://alcachofra.net/IR2117-diagram.pdf
    http://alcachofra.net/IR2117-spice.pdf

    Your have the diagram and spice output image.

    Can I have some help, please?

    Thanks
    H. Martins
     
  2. kubeek

    AAC Fanatic!

    Sep 20, 2005
    4,670
    804
    I don´t think there is much help for this kind of behavior, the circuit should work flawlessly.
    Where did you get the IR2117 model?
     
  3. HMartins

    Thread Starter New Member

    May 10, 2011
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    2
  4. Jony130

    AAC Fanatic!

    Feb 17, 2009
    3,957
    1,097
    Well I think that your input signal DRAVE A is to low.
    Your input signal is equal only to 5V, and your input gate is supply from 15V.
    So I think you need at least 7.5V to IR2117 correct detected the high state at the input.
    According to the data-sheet you need 9.5V min because of input gate hysteresis.
     
  5. ifixit

    Distinguished Member

    Nov 20, 2008
    638
    108
    Hi HMartins,

    Try a logic input of at least 10V. The voltage between Vs and Vb needs to be minimum 10V and maximum 20V.

    Regards,
    Ifixit
     
  6. HMartins

    Thread Starter New Member

    May 10, 2011
    21
    2
    You are right. I suppose I read something stating TTL level and I assumed hysteresis was within 5V. Most obvious problems are difficult to clear out:D.

    I just resting adding a common emitter transistor to the out of the 74HC11 (in a page I didn't show) and it worked.

    Any better way of doing this level convertion? Common emitter transistors tend to saturate and produce an on to off extra delay.

    Of course I can use an opamp, but ... I suppose there are level shifters or converters I never used.

    Thank you
    Martins
     
  7. HMartins

    Thread Starter New Member

    May 10, 2011
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