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    Simple transformerless power supply design

    Is there any IC to make a simple power supply without transformer? (I don't want capacitor drop power supply). For example VIPER12A IC can be used to design a power supply but I want to use an IC that requires minimum components to design a power supply.

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    Re: Simple transformerless power supply design

    plenty that have just a buck choke - see power integrations ....



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    Re: Simple transformerless power supply design

    Hi,

    LM7805 for example.

    Klaus
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    Re: Simple transformerless power supply design

    I think the OP is referring to an off-mains supply hence the ref to the Viper12A, perhaps Klaus is being a little sarcastic with the 7805 reference ...

    if you google " off-line buck power supply" there are heaps of references ...

    e.g. http://www.ti.com/tool/PMP8550



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    Re: Simple transformerless power supply design

    Hi,

    I think the OP is referring to an off-mains supply hence
    With the given informations all we can do is guessing.
    The OP does not give a single information about input voltage (AC, DC, voltage...)
    And the OP does not give a single information about output voltage (AC, waveform, DC, voltage, current....)

    Klaus
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    Re: Simple transformerless power supply design

    Um, the clues are there - doesn't want a capacitive dropper - so AC in, likely mains, and Viper12A, an off-line controller chip, and the word - non isolated - implying it would usually be isolated from the mains ....


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    Re: Simple transformerless power supply design

    Hi,

    I see your point. It's not your fault... in opposite.. you do a good job.
    But is it the job of forum members to read between the lines?
    Or do an internet search what a viper12a is, download the datasheet and read through it to find out what the OP needs?

    I'm used to get clear specifications. Values with units, technical terminology...
    My personal opinion is that the OP needs to give unabiguous informations.. and ask a clear question.
    And that's what forum rules tell.

    And yes, I expected that the OP is not looking for a 7805 ... but doesn't it fit to all the given requirements?

    Klaus
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    Re: Simple transformerless power supply design

    the 7805 reply was "tongue in cheek" as we say ....



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    Re: Simple transformerless power supply design

    Quote Originally Posted by mdaupu View Post
    Is there any IC to make a simple power supply without transformer? (I don't want capacitor drop power supply). For example VIPER12A IC can be used to design a power supply but I want to use an IC that requires minimum components to design a power supply.
    yes there are like lm2576-12
    and xl6009
    very nice ic have fun dear mdaupu



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    Re: Simple transformerless power supply design

    After many, many years in this and several other online forums, one does indeed becomes exasperated with vague requests. And more so when one attempts to provide an answer, the OP will come back with another set of conflicting requirements which were not originally outlined.

    Therefore, I fully understand Klaus' dry humor.

    When I see such a request, more so if it comes from a first time poster, I hold on the comments although I revisit the thread to see how all went down.
    My batteries are recharged by "Helpful Post" ratings.
    If you feel that I've helped you, please indicate it as a Helpful Post



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    Re: Simple transformerless power supply design

    Dear Mr Schmitt trigger - I fully understand - all this is a product of the " ask google" phenomena - where students etc can only process and absorb small bite size chunks of information as seen on google etc ...

    the idea of sitting down with a pencil and paper and fully outlining what they intend to do - before asking questions - and therefore solving and answering their own questions at the start and refining what they need to know - is a foreign concept to many lay people ...



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    Re: Simple transformerless power supply design

    Transformer less Power Supply. One of the major challenges during a circuit design is to generate low-voltage DC from AC to power the circuit. There are many methods to convert AC voltage into DC. The most common method is the use of a step-down transformer to reduce 230V AC to a lower value AC.

    Click image for larger version. 

Name:	89f85712f7bcce5ae6ee96a496a41e60.png 
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ID:	155715



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    Re: Simple transformerless power supply design

    Although post #12 text mentions a step-down transformer, the schematic is a capacitive-drop method which is frequently used as an alternate due to its lower cost and less bulk. It may suit the purpose, although component values need to be carefully designed. Was it a bad experience with this topology that makes you wish to avoid it now?



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    Re: Simple transformerless power supply design

    The OP expressly did not want a cap dropper solution ....



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    Re: Simple transformerless power supply design

    here's some that may be good for you...in the pdf in the top post...just ignore the cap dropper
    https://www.edaboard.com/showthread....s-without-SMPS



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