Transistor ST83003 negative voltage issue

Discussion in 'General Electronics Chat' started by makrotek, May 24, 2016.

  1. makrotek

    Thread Starter New Member

    May 24, 2016
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    I charge 250VDC ( 80khz, square wave ) to a transistor ST83003, I got -12V between two
    wave. I am looking for a solution for the -12V issue. Anyone have the solution
    please advise. Thanks.
     
  2. #12

    Expert

    Nov 30, 2010
    16,257
    6,757
    Post your circuit drawing.
     
  3. makrotek

    Thread Starter New Member

    May 24, 2016
    4
    0
    Circuit drawing attached. Please advise. Thanks.

     
  4. makrotek

    Thread Starter New Member

    May 24, 2016
    4
    0
    Circuit attached. Thanks.
     
  5. #12

    Expert

    Nov 30, 2010
    16,257
    6,757
    The only place I can see where you have a negative voltage is R80. Why is it connected to -16 volts?
     
  6. makrotek

    Thread Starter New Member

    May 24, 2016
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    0
    The -16 is for adjusting zero voltage for other control.

    We measure from the output the negative voltage as described in the attached document.

    Just like jumping on a bouncing bed. The higher the positive charge, the higher the negative charge generated.

    I have used this circuit for year. Now I want to solve this issue. It seems that after charging the transistor, the transistor will generate negative
    Charge. Please help.
     
  7. crutschow

    Expert

    Mar 14, 2008
    12,990
    3,226
    I see no ST83003 transistor in your schematic. :confused:
    Which one did you change?
     
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