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Reverse phase control

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by Phasor, Sep 25, 2002.

  1. Phasor

    Phasor Member

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    I am looking for a circuit for reverse phase control (also known in the lighting world as 'trailing edge dimmers').

    There seems to be very little technical information around - I can't find anything in the libraries, and the Net isn't very helpful either.

    I believe that the switching components used in commercial dimmers are IGBTs (Insulated Gate Bipolar Transistors). If anyone knows anything about these, can you tell me how they work?

    Any reverse phase circuits or info is much appreciated!
     
  2. star882

    star882 New Member

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  3. Phasor

    Phasor Member

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    Thanks star882, but I've already seen that page, and doesn't tell me anything that I don't already know. I am quite aware that most dimmers are triac based - these are leading edge dimmers, and are not what I am after!

    BTW, I am not looking to buy a dimmer - what I want to do is purely experimental.
     
  4. dave

    Dave New Member

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  5. kinjalgp

    kinjalgp Active Member

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    But why do you want to control it using trailing edge? What difference is it going to make in the controlled output voltage?

    Kinjal
     
  6. Phasor

    Phasor Member

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    The typical reason given for using the trailing edge, is longer bulb life (in lighting applications), as you are never switching it on at the peak of the AC wave. Also reduced transformer hum (in ELV lights) and reduced EMI (electromagnetic interference).
     
  7. kinjalgp

    kinjalgp Active Member

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