120VAC to 9VDC Power Supply

Introduction: 120VAC to 9VDC Power Supply

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    5 Discussions

    On further investigation I see you are using a wallwort to feed it. Could you show that in the drawing so everyone knows ...THANKS!


    Reply 8 years ago on Introduction

    my schematic software "Multisim" does not have one so i use the phoneplug instead of a jack.

    Are you feeding this "mains" voltage (120/240 VAC)? If so it is indeed very dangerous. If you using a step down transformer you should show that in the drawing. Keep in mind that these structables are used by newbees,and so you cannot assume knowledge on their part. Thy to explaiin EVERYTHING !! THANKS!


    I agree with nrclark. this is a bad design because:

    - it has the potential for DC coupling of the line voltage to the battery input
    - a lot of heat would be generated / wasted in the conversion
    - maximum input voltage 35V


    8 years ago on Introduction

    This isn't safe. The maximum rated voltage on that regulator is 35V. Linear-regulator designs like this should always have a step-down transformer at the input, unless you're using a regulator designed to work at line voltage levels.