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  1. #1
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    230v to 5v

    How to convert 230V / 440V A.C to 5V D.C with out using transformer.

    Is it possible?

    Could any body help me out?

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    5v transformer

    It is 100% possible to get 5 volts without transformers by the use of capacitors and resistors, but limited to some milliampheres. Also you may use a switch mode power supply. BTW what current you require?


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    230vac to 5vdc circuit

    it depends on what's the current rating ...

    read this to understand

    http://www.zen22142.zen.co.uk/Circuits/Power/tps.htm


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    5v without transformer

    Here below I've linked to a paper about this stuff, take care, capacitor power supply is different than conventional bridge-capacitor power supply, the first are basically constant current fed device, latter are voltage source. Anyway read the paper to gain more knowledge about performance, advantage, drawback and so on about this supply device class.

    A Capacitor-Fed, Voltage-Step-Down, Single-Phase, Non-Isolated Rectifier http://www.hamill.co.uk/pdfs/acfvsdsp.pdf


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  5. #5
    mfd
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    230v 5v

    There's 2 ways you could do it:
    1. CAPACITIVE TRANSFORMERLESS POWER SUPPLY or
    2. RESISTIVE TRANSFORMERLESS POWER SUPPLY

    Go to Microchip's web-site and do a search for application note: AN954

    Good luck,

    MFD


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    ac volte 230v to 5v convert do not transformer

    Suppose i am using transformer. ok

    I have planned for like below:

    Direct supply to transformer Which will convert 230 V Ac to 24 v Then use of Bridge rectifier circuit then regulator supply circuit.

    But When i am going different searches:

    I found that they are using One Varistor & a Capacitor Across the AC Supply before the transformer.

    Could anybody explain me What is the need/role of Varistor & capacitor before the transformer?

    Why we need a varistor?




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    5v power supply without transformer

    Quote Originally Posted by saumya_85
    Suppose i am using transformer. ok

    I have planned for like below:

    Direct supply to transformer Which will convert 230 V Ac to 24 v Then use of Bridge rectifier circuit then regulator supply circuit.

    But When i am going different searches:

    I found that they are using One Varistor & a Capacitor Across the AC Supply before the transformer.

    Could anybody explain me What is the need/role of Varistor & capacitor before the transformer?

    Why we need a varistor?


    buddy u are asking same question every where ...do some googling too :D


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    230v ac to 5v dc



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    what do represent by 230v ac

    Hai Saumya-85. As you intend to get only 5 volts regulated DC, it is sufficient if you use a 9 volt transformer for the rectifier as the margin voltage required for regulation is about 3 volts above the required voltage. Capacitors are used to filter any ripples as well varistor is used to supress any spikes on the supply. Good luck


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    circuit for costant 5v without using smps

    Hi saumya

    The main function of varistor is

    to protect circuits against excessive transient voltages by incorporating them into the circuit in such a way that, when triggered, they will shunt the current created by the high voltage away from the sensitive components.

    i think that main function of capacitor is supress noise and smoothen the input sinewave


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    230v to 5v circuit

    Saumya, you did not answer the Pranam's query, what is the current demand from the 5V dc supplyu you want to make

    if what all you need is say 5V 500mA, a transformer of 230 primary and 8V secondary with 750 mA capacity will do
    You may use a 4 diode bridge rectifier, have a filter with 2000uF/16V. use a 7805 regulator IC and a good heat sink
    with a 0.1 uF cap each connected at INPUT & OUTPUT TO common Gnd, AND WITH SAY 470uF/16V FILTER CAPACITOR at the output, you are ready to use it.
    Ofcourse you need a container to house all these stuff.
    Hope you can make a schematic from the explanation given.
    download datasheet of 7805 from www.alldatasheet.com and study it
    you will appreciate all issues .




    .


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    5 volt transformer

    I require 5Volt DC with2A>I <3 Amp Current rating.

    Current should be between than 2A to 3A.

    But preferable 3A.


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    230v to 5v dc schematic

    Quote Originally Posted by saumya_85
    I require 5Volt DC with2A>I <3 Amp Current rating.

    Current should be between than 2A to 3A.

    But preferable 3A.
    You may consider making a switch Mode power supply. Link for datasheet of such design is attached. as collected from Power integration inc

    http://www.powerint.com/sites/defaul...tny274-280.pdf

    they have Top, TINY and Link switches.
    complete design can be obtained from their site. These chips are sold in India, so you should have no problems at all.


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    230 5v ac dc schematic

    Quote Originally Posted by saumya_85
    I require 5Volt DC with2A>I <3 Amp Current rating.

    Current should be between than 2A to 3A.

    But preferable 3A.
    Hai Saumya_85, In case you need 5 volts at more ampheres, use 0-9 transformor 3A, rectify and filter the output and feed it to the High current voltage regulator which will supply 5 volts at 3amps..Do not forget the 'Helped me"button if you find this post has helped you. Good luck


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    230 to 24 converter

    Quote Originally Posted by pranam77
    Quote Originally Posted by saumya_85
    I require 5Volt DC with2A>I <3 Amp Current rating.

    Current should be between than 2A to 3A.

    But preferable 3A.
    Hai Saumya_85, In case you need 5 volts at more ampheres, use 0-9 transformor 3A, rectify and filter the output and feed it to the High current voltage regulator which will supply 5 volts at 3amps..Do not forget the 'Helped me"button if you find this post has helped you. Good luck
    Thanks pranam for your support.

    Could u tell me why 2N2955 is required in your schematic?



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    trafo van 230 naar 5v

    It is used too provide the 3 amps current, with the volatge at the regulated level. 5volts in this case. Do not forget to press the 'Helped me"button if you find this post has helped you. Good luck


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    230v bridge rectifier

    Quote Originally Posted by pranam77
    It is used too provide the 3 amps current, with the volatge at the regulated level. 5volts in this case. Do not forget to press the 'Helped me"button if you find this post has helped you. Good luck



    Thanks



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    230 ac to dc 5vdc

    Hai Saumya.
    Please note that these circuits given by me will work fine when you use it with the rectified and filtered DC derived from a transformer only.


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    ac to dc without transformer

    hi
    It is may be danger to use 230-5v


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    230 to 5v circuit

    Quote Originally Posted by smxx
    hi
    It is may be danger to use 230-5v
    YES it IS HAZARDOUS to use non isolated supplies, as many a times , our designed circuits are used by others without proper understanding and are sure to be ELECTROCUTED IF THEY COME INTO CONTACT unknowingly, and the responsibility directly falls on us if traced legally.