Question on a MOSFET

Discussion in 'General Electronics Chat' started by killivolt, Jul 23, 2015.

  1. killivolt

    Thread Starter Active Member

    Jan 10, 2010
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    [​IMG]

    Has anyone seen this configuration? Out 2 and 3 are going to BNC outputs but I can't tell what the MOSFET is doing? Is the MOSFET only being used for its diode? Or is something fancier going on here?

    Thanks for any responses in advance.

    kv
     
  2. kubeek

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    Sep 20, 2005
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    I´ve seen this used as a level shifter.
     
  3. killivolt

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    Jan 10, 2010
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    From what I gathered on the "NET" most of the level shifters I see use Op-amp designs. I was thinking this was conditioning the voltage on OUT 2, and stabilizing it's voltage for a constant sink source.



    kv

    Edit: Oh, and thanks for the info :D
     
  4. jpanhalt

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  5. kubeek

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    Well this is not a level shifter in the linear sense, where you really would use an opamp, this is a level shifter for digital signals. If I remember correctly it can be used in both directions.
     
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  6. cmartinez

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    Yes. I've used that configuration before, it's a bidirectional level shifter used to interface 5V to 3.3V logic. Check the attached document.
     
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  7. cmartinez

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    Aaaargghhhh... John beat me to it! ....
     
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  8. killivolt

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    Jan 10, 2010
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    Thanks all. I was thinking some sort of Logic circuit but; just couldn't fit it into anything I'm familiar. I used the BNC connections back sometime ago on old standard Def switchers but; SDI logic source was embedded for switching video. Now we have HD-SDI.

    Thanks again. kv

    Edit: I got some reading to do lol
     
  9. MaxHeadRoom

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  10. killivolt

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    Last edited: Jul 23, 2015
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