Go/No-Go Test for Shunt Regulators

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  • JEWilson
    Badcaps Veteran
    • Sep 2007
    • 369
    • Scotland, United Kingdom
    #1

    Go/No-Go Test for Shunt Regulators

    I have a problem with +5VSB voltage regulation being slightly out of spec.
    The PSU issues a single crackle noise when the PSU is powered off.
    This noise appears to be coming from the switcher.

    I am testing a number of components on the +5VSB rail to determine if ok.

    The PSU has a TL431C shunt regulator
    see further http://pdf1.alldatasheet.com/datashe...CS/TL431C.html

    Is there an easy way to test this out of cct with a meter?

    Any advice appreciated. Thanks
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