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  1. #1
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    High voltage switching circuit

    Hi all

    I have 4 different module, each module gives different types waveforms i.e sinewave , square wave sawtooth wave and pulse wave. i have 4 channels in which i want to get all those waveforms

    Challange:
    1. Any waveform can be connected to any channel.
    2. i may need 16 switching circuit (4 modules x 4channels )
    3. low Cost MOSFET but high Rds on

    I have designed it using N type Mosfet based switching circuit but looks like -ve wave putting lot of stress on Opto-coupler. need your suggestion

    Click image for larger version. 

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    Click image for larger version. 

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  2. #2
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    Re: High voltage switching circuit

    Presently, your question is missing any substantial specification (voltage, current, signal frequency, switching speed). Did you intentionally strip of time and voltage axis from the waveform? If so, my general answer is: It's surely feasible with electronic components...

    - - - Updated - - -

    The optocoupler circuit doesn't seem to make much sense as sketched.



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  3. #3
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    Re: High voltage switching circuit

    Sorry for not providing adequate info
    1. voltage to be switched 250Vp,
    2. Current :maximum 80mA
    3. maximum waveform frequency :4kHz
    3. switching time: 1Minute or more

    In circuit i have intentionally increased switching time just to visualize waveform clearly.



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  4. #4
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    Re: High voltage switching circuit

    Hi,

    Your question seems unattended to because it is difficult to relate your schematic to your question. I have a few questions that I feel might help you.

    What do you mean by channel? What do you mean by module? What's the voltage source V1 doing? Why do you think you need two optos and two MOSFETs? Why is V1 connected to the secondary of your transformer like that? Where is the load, is it Rser=0.2ohm? 5V/0.2R=25A peak current from V1, is that what you have in mind? Where is this current going to?

    There are a lot more questions to ask. You probably need to explain what you are trying to achieve in more detail so we can help
    -------------
    --Akanimo.



  5. #5
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    Re: High voltage switching circuit

    Well suited for solid state relays if you can tolerate the high resistance:
    https://www.digikey.com/product-deta...4CT-ND/1212845

    Or "Telecom" relays are very cost effective for ~275V/2A (or less) applications.



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