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  1. #1
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    Using TL431/OPTO feedback with LNK304 based HV Buck

    Hi,
    For HV Buck using LNK304 as on page 6 of datasheet (2nd schem down)...

    LNK304 datasheet
    http://www.mouser.com/ds/2/328/lnk30...306-179954.pdf

    ...Is their any reason that we cant use a TL431 and a divider with the opto instead of just a zener?
    (we donít want the zenerís poorer tolerance)

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  2. #2
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    Re: Using TL431/OPTO feedback with LNK304 based HV Buck

    Try it. I can't see any reason it shouldn't work but do be aware of the combined gain of the switcher and TL431 causing stability problems.
    I think the data sheet specifies a Zener because the idea of those devices is minimal cost and adding a TL431 would negate that.

    Brian.
    PLEASE - no friends requests or private emails, I simply don't have time to reply to them all.
    It's better to share your questions and answers on Edaboard so we can all benefit from each others experiences.



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