is ringing in a transformer bad?

Discussion in 'General Electronics Chat' started by lokeycmos, Jan 18, 2013.

  1. lokeycmos

    Thread Starter Active Member

    Apr 3, 2009
    432
    7
    so i just breadboarded this circuit along with a hand wound transformer.

    http://www.maximintegrated.com/app-notes/index.mvp/id/1923



    the circuit operates correctly and seems to function as it should, but i was just wondering if ringing in the circuit will cause any issues down the line? is there anything i can do about it? it is oscillating around 200khz to 300khz. the ic is a square wave oscillator with opposite pulses on pins 1 and 8. i attached a few pics too. pic 1 is the primary side.pic 2 is secondary and pic 3 is breadboard.
     
    • 1.jpg
      1.jpg
      File size:
      283.2 KB
      Views:
      44
    • 2.jpg
      2.jpg
      File size:
      281.9 KB
      Views:
      42
    • 3.jpg
      3.jpg
      File size:
      306.5 KB
      Views:
      43
  2. BillB3857

    Senior Member

    Feb 28, 2009
    2,400
    348
    Can't help much with your ringing problem other than to observe that matching load to output impedance will reduce it. I do have to say I like to see you scope is still in operation! I built one of those back in 1965! Great scope for hobby use at the time. 5Mhz bandwidth, DC coupled.... What more could you ask for? Too bad it suffered from DC drift so badly.
     
  3. shortbus

    AAC Fanatic!

    Sep 30, 2009
    4,013
    1,531
    Going to ask a dumb question here.:) What causes a transformer to ring? First time hearing about this.
     
  4. BillB3857

    Senior Member

    Feb 28, 2009
    2,400
    348
    Distributed capacitance with the windings form resonance with the inductance. Recall that voltage is maximized at resonance in a parallel tuned circuit. A cap across the coil will lower the ringing frequency. Step changes in the current through the inductor initiate the ringing.
     
    kubeek likes this.
Loading...