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    This is a transformerless power supply for low current applications. C1 is the X rated AC capacitor that reduces high volt AC. D1-D4 rectifies AC to DC and C2 removes ripples. R1 is the bleeder to remove stored current in AC when power is off. R2 limits inrush current. A Zener can be used in the output to get regulated DC.

    Caution! Circuit is lethal since it carries high volt AC. Do not touch or test when connected to Mains. Enclose in a shock proof case.

    Transformerless Power Supply Circuit Schematic

    transformerless power supply

    attentionThe author D Mohankumar is not an active member anymore. Please take into consideration that the presented information might not be correct.
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    199 Responses to "TransformerLess Power Supply 12V 100mA"

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    1. Pls. provide me the circuit for charging the 2.4 V rechargeable battery using resistor & capacitor, but without transformer.current is 50MA.

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    2. good day!!! can u help me with a transformerless power supply with a 6v output at 500mA….plz…thanx

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      • D Mohankumar D.MOHAN KUMAR says: on January 18, 2010 at 2:28 pm
          member

        It is difficult to get higher current from a transformer less power supply. Even with a 225K capacitor, maximum output current will be 100 mA. To get high current, transformer is necessary. Transformerless power supply is used to power low current circuits drawing less than 30 mA current

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      • ..good day sir!, what happen if values of the components will be changed? Say from 225K 400V to 225K 630V and 100R 1W to 100R 5W?

        ..THANK YOU VERY MUCH!

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      • khurram says: on June 5, 2012 at 12:38 am

        Sir it this above transformer less power supply is accurate because i want to make a device or we say product

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      • D Mohankumar D.MOHAN KUMAR says: on January 18, 2010 at 2:32 pm
          member

        The same circuit can be used for recharging 2.4 volt battery. Reduce the value of C1 to 105K and fix a 3 volt zener across the output with cathode towards positive

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      • Wouldn’t it be possible to increase the output current by exchanging r2 for a smaller value resistor and parallel circuits of capacitors?

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      • Sir, is this circuit will produce heat??

        is it applicable for industrial application??

        if any drawback in this circuit pls advice.

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    3. what is the best amount of voltage and current supply of a passive infrared circuit usig M7615 as passive infrared controller??can u also email me the circuit of a suitable transformerless power supply…if u also have any circuit for a passive infrared sensor, can u also email me…..pls. reply ASAP..thanx a lot..

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    4. D Mohankumar D.MOHAN KUMAR says: on January 18, 2010 at 2:35 pm
        member

      It is necessary to know the power rating of the M7615. It is better to use a step down transformer because Mains spikes may give false triggering in sensor circuits

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    5. Krishna says: on March 3, 2010 at 4:28 am

      Thanks for the information, its nice…

      i want to modify the same circuit for the output of 12V and 2 amps…

      can you please tell us the required changes in the circuit…

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    6. D Mohankumar D.Mohankumar says: on March 3, 2010 at 11:48 am
        member

      It is difficult to get high current from capacitor based power supply. It can give maximum 100 mA with a high value capacitor like 225K.These designs are used for low current applications.Maximum 50 volt can be obtained. For high current, transformer is necessary

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      • D.Mohankomar,
        gud day!!!
        do i need to change the value if use the 110vac as an input instead of 220vac … pls advice
        regrds,
        czar

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      • jayakrishnan says: on December 28, 2011 at 12:22 pm

        Hello,

        I need to construct a circuit which will operate a 12V or 48V DC relay from 230v AC mains.That is the relay should be closed when AC mains in present ans it should be open when Mains in not present.
        How to make such a circuit without using transformers? I have required number of 48v and 12v DC relays. Please help

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      • I need to construct a fan circuit which will operate a 12V or 48V DC relay from 230v AC mains.That is the relay should be closed when AC mains in present ans it should be open when Mains in not present.
        How to make such a circuit without using transformers? I have required number of 48v and 12v DC relays. Please help

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      • Hi,
        It is possible to get more than 50V of current from this circuit with some modifications. I have extracted upto 180V to work for around 40-50 LED’s and it runs quite well.

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      • chandran says: on August 18, 2013 at 5:29 pm

        Plz inform by wiring diagram&.transformerless one only
        parts of a charger of out put 6Volts 500mA dc with 11ovolts Ac&230v acin

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      • (1)Plz send me circuit diagram with parts7value of a transformerless Charger of 6Volts 500mA

        (2)Plz also send me the circuit diagram of a common table Raleigh Fan with parts&its value of 3 speed working on 230Volts Ac.50Hz with Induction motor &capacitor&3 way speedcontrol etc by reply g mailof mine ,thanks chandran 20-11-2013

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    7. D Mohankumar D.Mohankumar says: on March 4, 2010 at 4:31 pm
        member

      You need not change the values.Try with 110 v input. If the output voltage is low use 0.1 UF capacitor in the place of 225k

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      • ghanshyam says: on September 1, 2011 at 8:49 pm

        is it possible to use only resistances (no capacitor) to make transformerless power supply…..? sir, i hv just started to make mini project… power supply is my first project.. what should i try next project??…..

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      • can i get 15v, 150ma with transformerless power supply.

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      • khurram says: on June 5, 2012 at 12:45 am

        Sir is it efficient or accurate

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    8. Kimseng says: on April 14, 2010 at 4:26 pm

      Dear D.Mohan Kumar,

      Can you tell me? if I want to change the outut voltage from 12V to 5V? And after changing what is the maximum output current of the circuit?

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      • SIR ,IWANT THE MOST IMPORTANT PROJECTS OF CELLS USING THE CIRCUITRY OF THE NANOTECNOLOGY.BY USING THE ELECTRONIC CELLS

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    9. D Mohankumar D.Mohankumar says: on April 15, 2010 at 4:15 am
        member

      The current from the power supply depends on the Capacitor C1. 225K can give around 100 mA in ideal conditions.You can reduce the output voltage to 5 volts by adding a 5 volt Zener across the output.In this case, output current will not be reduced much

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    10. hi…..im fr indonesia….i love most ur design i hope you have another one that easy to DIY for beginer…
      Back to topic …so….about the voltage that out from this design depend to ZD value…..?

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    11. D Mohankumar D.Mohankumar says: on April 23, 2010 at 1:43 pm
        member

      The output voltage and current depends on the value of dropping capacitor C1. With a 225K capacitor around 12 volt and 100 mA will be available.This can be regulated from 3 volt to 10 volts using Zener

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      • TAPAN BANERJEE says: on April 1, 2012 at 5:42 pm

        Sir,
        I have made a remote controlled regulator for celling fan, but the problem is the power supply is made by a stepdown 9-0-9v, 250ma transformer because there is a zero crossing detection. I want a transformerless power supply of 9-0-9v with zero crossing detection can you help me with a circuit that can meet my requirement. If yes, then pl.send the circuit at my email address.

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    12. Hi guys thanks for giving this project on a transformerless power supply. I want to know the calculations involved in tin design of this project and to know if it worked because i want to construct it. Thanks

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      • The project work…i have realized withe 2 electrolitic capacitors anti serial – ++ – of 4,7uF 450v with a final diode zener 12V 5W and give me 140mA.

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    13. Hi thanks for giving out this project. I want to know the calculations involved in the design and also if it worked. Thanks

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    14. Sorry, but 225k is a capacitor of 2,2uF or 0,22uF?
      Thanks.

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      • D Mohankumar D.Mohankumar says: on May 9, 2010 at 7:22 pm
          member

        225K capacitor is 2.2 uF.It is X rated Metallized Polyester Film capacitor 400 V AC.

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      • nil agrawal says: on December 3, 2013 at 6:17 pm

        dear

        pl give brief detail of x rated ac capctior . why we choose Ac intsted of dc? & why Metalised Polyster type Not polypropelne type?

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    15. @ Tami

      The project work…i have realized withe 2 electrolitic capacitors anti serial – ++ – of 4,7uF 450v with a final diode zener 12V 5W and give me 140mA but the capacitors are very hot..it’s best to put Metallized Polyester Film capacitor 400 V AC.

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    16. Thanks pls i want to know if the heat generated can make the capacitors go bad in a short time and can a transformerless power supply circuit of 12v and 100mA power a battery charging circuit of 12V 1mA. Thanks

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      • D Mohankumar D.Mohankumar says: on May 17, 2010 at 7:36 am
          member

        Capacitor will not generate much heat.It will not be destroyed due to heat problems.Dielectric of the capacitor will be destroyed only if the line voltage goes above the rated voltage of the capacitor.It is better to avoid capacitor power supply for battery charging, if the battery is kept open.Generally these forms of power supply are not recommended to use in circuits that require human contact .If you want to charge a battery that is kept in an enclosure, use a series resistor at the output to get desired current. Use ohms law for the current.

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      • Sir
        i need 6v dc supply
        can u tell me how could i get 6v dc from above circuit i.e. Transformerless Power supply

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      • D Mohankumar D.Mohankumar says: on May 31, 2010 at 10:28 am
          member

        Connect a 6.1 volt Zener across the output

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      • nil agrawal says: on December 12, 2013 at 6:05 pm

        DEAR SIR

        how can i check capacitor specified voltage shows on body.& leakage of it.

        i want to check electrolytic capacitor & multilayer ceramic capacitor voltage rating & leakage of it.

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    17. Thanks for your support. The battery charging circuit in question can be used to charge a 6watt or 12watt battery. The input voltage ranges from 9V To 40V and the current is 1A. Thanks for your contribution

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    18. I have a pumpmotor 240VAC / 50W that is controlled by a mecanical thermostat switch. I would like to indicate that it is running with a simple LED in serial with the pump somehow. The problem is that i only have very limited physical access only to the switch that controlls the 240VAC for the pumpmotor. How can i sifon off 5V/20mA for the led with som simple componets that will not significantly affect the pumpmotors capacity? I tried connectin a cheap battery eliminator 240VAC/5VAC but that made the pump slow. Im looking for a super simple solution and i dont want to use a battery that recuires changing.
      I am wondering if perhapps a simple ferite ring with a few loops (<5) and a small resistor on the secondary side could be used as a transformer. How would one go about calcuating the number of loops to get 5 v/ 20mA. Would this affect the pumpmotor. Will I perhapps need an extra sparc protection on there realay since I have a serial tranformer. I have electronic schooling but it was to decades ago.

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    19. D Mohankumar D.Mohankumar says: on June 1, 2010 at 4:33 am
        member

      The most simple solution to light an LED is to connect a 47k 1 watt resistor in series with the LED . This should be connected across the phase and neutral after the pump switch.The brightness of the LED will be low since it is lighting only in the positive half cycle of AC.

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    20. Thank you for your quick and wize reply. Im sure it would work if i had access to the neutral cable after the pump. 240V/47K equals 5,1mA thru the LED. But would it not be to much voltage for a “simple led” to handle?
      I was schooled 20 year ago and have not practised electronics since. Back then the diodes we used “handled” quite low voltages i think it was 0,7V – 12V. Does modern day LED’s handle 240 V or how would the voltage be over/on the LED. Im a bit afraid it might blow up violently taking out an eye and a few brain cells
      (murphys law :-) ).

      Sadly I do not have access to the neutral wire after the pump. I want to put the indication diode at the switch (in serial somehow). Im sorry for the unclear problem description. What i would like, if it possible, is some simple cirquit thingie in serial with the switch. That would not affect the pump noticeably.

      If i parallel connect three 10 ohm resistors i would get a 0,03 ohm resistor. 10+10+10/10*10*10=0,03 ohm.
      In serial with the switch that would make 240VAC*0,03 Ohm=7,2V over the resistor(s). If i then also put a (diode and a 360ohm(7,2V/20mA) in serial) in paralell over with the 0,03 ohms. What would i get? What kind of Watt tolerance resistors would i need for this? I cant realy figure out the watt here and i dont want redhot resistors just to lite the LED. Would this be safe?

      Here is a link to the boyler thermostat i want to put the indicator led in serial with. It’s basicaly a normal cirquit switch. http://www.ra.danfoss.com/TechnicalInfo/Literature/Manuals/04/ICPDP10F102.pdf

      With grattitude
      Nick

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      • Nick,

        You can loop your hot wire going to the pump through a CT (current transformer), the turns ration determines the current in CT winding, for example if your pump current is 1Amp then 100turns will induce 10mA in the CT coil, you can use this to light up a LED.
        You can try a small ferrite core and wind the magnet wire onto this.

        John.

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    21. D Mohankumar D.Mohankumar says: on June 2, 2010 at 2:12 pm
        member

      Do not think too much theory. Just connect the LED with a 47 K or 56 K resistor( 1/2 watt) .LED will glow with half brilliance. But you have to connect it between the phase and neutral lines.

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    22. how can i calculate thecharge rate of a battery and to know the charge rate of my circuit. also the calculation to know the capacitor to use in rectification

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    23. nouman nayyer says: on July 25, 2010 at 9:06 am

      dear sir
      sir i made it but with correct component but after few minutes the 100uf-25v capacitor overheated and destroyed and the voltage was also 33 volts dc…..
      plz help me regarding this
      thank u

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    24. The problem is with the capacitor C2. Use 100 UF 100 Volts capacitor and check output voltage. If required use a 12 volt zener across the output

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    25. sir i have a small problem that i need a circuit without transformer which provides 12v 1 ampere current can u please give me suggestion

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    26. D Mohankumar D.Mohankumar says: on July 27, 2010 at 4:26 pm
        member

      Transformerless power supply can give only 500mA or less current.If you want 1A,use a transformer

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      • sir you are saying that transformerless power supply can only give 500mA,then how the cahrger of a mobile phone is giving 895mA??
        i checked that on NOKIA charger..its rated as 875mA output.kindly elaborate the reason
        thanks

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      • That is because that uses smps high frequency switching which is very difficult to design and make.

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      • phone charger is not include as a transformerless charger..it is a SWITCHING MODE POWER SUPPLY..it used a small trnsformer that trigger by a mosfet…try to searched in google and learned abt SWITCHING MODE POWER SUPPLY…it gives more power output than a conventional charger..

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      • Transformerless power supply can give only 500mA or less current.If you want 1A,use a transformer

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      • Hi,
        It would be great if I am able to draw 350mA current from the same circuit to run a 1w (3.5v 350mA) High power LED. In a previous post I have mentioned that I can make 40-50 LED circuit with LED’s rating 3.5v 20mA. But I would like to ask, what would happen if I connect 2 or 3 225K caps in this circuit, with a changed C2 value and lower voltage Zener, cant it give me my required output (Capacitance increases when connected in parallel).

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    27. japanjot singh suri says: on September 1, 2010 at 9:58 pm

      hello sir, i am doing electronics engg,your post seems to be very usefull to me and my frnds, sir as we work on simple projects, we require batteries,and the main problem is bulky transformers in the project, sir we require 6v 350 to 500 ma dc supply from 230v w/o transformer to charge 4v 1amp battery, and we also require 8v 500 ma supply to charge 6v 4.5 ah battery.

      acording to your circuit i judged dat we could do dat using zeners of our required voltage, but how to calculate and adjust the output current which we would get

      would be glad if u would help us
      thank you :-)

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    28. Is there a way that we could increase the Amp supplied by this Circuit,Cause i’m trying to develop a LED tube Light which Req 12 V n 1 AMP,Thnks

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    29. Dear sir, is this power supply enough to activated the panic alarm circuit?

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    30. D Mohankumar D.Mohankumar says: on November 9, 2010 at 1:18 pm
        member

      Dear Vincent

      Th Capacitor power supply can be used for any circuit that requires less than 100 ma current including the Panic alarm circuit. But relay will not work satisfactorily in capacitor power supply since it requires more current. If you use Capacitor power supply, take all precautions mentioned in the article. The power supply section should be isolated from the circuit. Do not touch or trouble shoot the circuit while it is connected to mains. It can give a fatal shock.

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    31. @D.Mohankumar

      sir you are saying that transformerless power supply can only give 500mA,then how the cahrger of a mobile phone is giving 895mA??
      i checked that on NOKIA charger..its rated as 875mA output.kindly elaborate the reason
      thanks

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      • D Mohankumar D.Mohankumar says: on November 29, 2010 at 3:48 am
          member

        Dear Khayyam

        Mobile charger uses SMPS power supply which can give up to 1Amps current.There are components to give high current.In simple transformerless power supply, the current depends on the value of the capacitor.That is around 100 mA / 1uF.

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      • Sir, I am trying to do a mobile charger ckt. kindly tell me if I can check this ckt using a common board, or will I need a PCB to test this ckt.
        I want to know if the high voltage, high frequency input will short the board pins..

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    32. Hello Mr Mohankumar thanks for this circuit, I am planning to use this circuit in one of my patented eco switches, but the design company inform me that it is only able to deliver 40mA.I need a circuit that can deliver over 60mA.Please confirm that this circuit can definately deliver 100mA.My email address is prad123rita@yahoo.co.uk kindly advise.Matter urgent.pradeep

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    33. sir i wantcircuit of Transformerless power supply only230v to 12v 500mA /200mA

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    34. sir we want circuit of 220v to 12vdc 200mA detail please

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    35. hi sir, I am also an electronics engineering student . we are going to build a transformerless power supply 24V / 3A and no using of IC . can you please give me the circuit? thanks in advanced .

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    36. sir thanks for poer supply but i want 1qu. iwant circuit of 12v 12amp transformerless shock proof

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    37. Sir,is this power supply can use to this circuit???
      http://electroschematics.com/5643/sensitive-clap-switch/comment-page-2/#comments

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      • thanga says: on June 6, 2013 at 1:24 pm
          member

        i think the above circuit will work fine with the clap switch circuit you mentioned….

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    38. sir,

      The circuit is designed for 12v 100mA. Will you help me sir as to what component should i replace/adjust to have a 12v 500mA.

      Thank you so much in advance.

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      • The out put voltage from the Transformer power supply depends on the value of the AC capacitor used. As a rule 80-100 mA current will be available per 1 uF. If you want 500 mA, you have to use Five 1 uF AC capacitors in Parallel. But the output current depends on the input AC also. Accurate output cannot be expected and high current devices cannot be connected to this power supply. This type of power supply is used only in low current applications requiring less than 100 mA current.

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    39. jhun s. viloria says: on April 24, 2011 at 6:43 pm

      Dear Sir,
      I just want to ask you about my problem,i want to buy a transformer with 2 separate secondary outputs,1 is for 50v another 1 is for 25v,the case is..im trying to fix a bose amplifier board,there are 2 separate supplies,the first supply is having a 25v capacitor and another 1 is 50v…i want to make sure from you what is the correct specs of the transformer im going to buy,im not sure whether the output should be at least 20v for the 25v capacitor and at least 40v for the 50v capacitor.
      Please guide me.
      Thank you very much in advance.

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    40. Abhishek kumar says: on April 27, 2011 at 11:04 am

      Hey everyone,
      I want to design a transformerless power supply, whose output must be 5V,200mA.
      Please guide me how yo do…….

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    41. patrick vaz says: on May 4, 2011 at 8:58 am

      Hi,

      If i need 12v & 20mA, instead of 100mA what changes in the components i need to do,

      thanks in advance

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      • This transformer less power supply is already giving an output of 12V, so you can use it, actually you can use any 12V power supply that can output a current higher than 20mA because the device you use will consume as much power as needed.

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    42. sir i tried the power supply for another circuit but the R2 is burned off, i used 100R 1 watts .and another problem is the R3 is also becoming hotter.kindly reply sir.

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    43. sir i tried the power supply but the R2 is burned off, i used 100R 1 watts .and another problem is the R3 is also becoming hotter.kindly reply sir.

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      • depend on ur load…more load current getting more hotter til burned it…try to put higher resistor up to 1k wattage of 3watts…for better performance

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    44. ThanhHoangDang says: on July 23, 2011 at 7:46 am

      Hi sir,I’m doing this circut,everything ‘s ok but why is the R3=220(Ohm) too hot,I’m worrying it’ll be destroy.I don’t know what’s wrong with it.pls send to some solution to do it better soon,thanks sir so much for this!

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    45. Dear Sir.
      Thanks a lot. I use this circuit to charge my LED lamp battery and working good.

      Regards
      karsang dorji
      Bhuatn

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    46. @abhin raj
      @ThanhHoangDang
      maximum current in the circuit is 100ma(0.1A)
      now apply Ohms Law , power is equal to current squared into resistance
      P=I^2R
      for R2 we get 0.1^2X100= 1 watt
      Use twice this value
      So we need to use a 2 watt resistor for R2
      Similarly for R3 we get 0.1^2X220=2.2 watts
      Use twice this value which comes to 5 watts
      So we need to use a 5 watt resistor for R3
      hope it will keep the circuit cool
      regards

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    47. Bhanu Reddy says: on August 3, 2011 at 7:24 am

      I would like to stepdown the voltage from 3 phase system..i dont have the neutral..is there a way with out using transformer to step down (12 v 50ma)voltage from 220v 3 phase 3 wire system..

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    48. sir,i wud like to make a restless(always working) led flasher circuit which works on 6v,is it possible to connect this circuit to power flasher always from 230v ac supply?plz reply

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    49. plz sir , i tried the transformer less power supply shown in this site , but using 5.1 v zener , in case of open circuit output is 5v but when loading, output becomes 1 volt , so how to fix this problem or how to design suitable trans.less power supply to feed 20 leds parallel together with output 5v sharp.

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    50. P.Jagannathan, says: on August 9, 2011 at 2:36 pm

      Thank you for the interesting circuit idea, can u please suggest alteration so that I can get 12V 210mA to light my LED which can give me 3W light

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    51. Can i use SMPS for audio amplifiers

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    52. Rajubhai Maru says: on August 12, 2011 at 2:50 pm

      Dear Sir, D.Mohankumar

      Sir i priped this circuit but R3(220R)is Very hot after 3 to 5 minitus & R2 also so whot can i do sir

      sir please replay me……

      Thanks

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    53. on the 100R1W and 200R1W resistor, can you please tell me what does R mean? thank you! :)

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    54. I want to replace the 9V battery with transformer less power supply. Please suggest. With Advance Thanks
      Kannan

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    55. sir i need transformerless (-35 to +35)volt dual power supply circuit diagram with 5amps current

      Like or Dislike: Thumb up 0 Thumb down 0

    56. Sir,
      How to design a dual 8V,100mA power supply? which regulator IC can we use?

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    57. Plz also give me circuit diagram.

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    58. Doctor What says: on September 23, 2011 at 2:06 am

      Hey, love the circuitry, but how could i set it to 5V and 150mA?

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    59. Rohan Valvekar says: on September 24, 2011 at 9:50 am

      How to make 1amp 12v power supply ? or which capacitor to use to make the same circuit 1 amp output

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    60. Sir kindly take us to next level and with a bit complex circuitory tell us to get increased current

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    61. Thanks for this circuit it work i have been built for auto emergency light

      i want to build simplified 12v, 5v power supply from main smps transformer that i get it from broken PC Power Supply Unit, can u give me the schematic?

      for your respone thanks before.
      i has been search for half year

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    62. asad ullah jan says: on September 30, 2011 at 6:48 pm

      my dear sir,
      i want to know about transformerless power supply,
      how can we built power supply from 220ac to 6vdc with the transformerless or capicito resister method,
      if u do, i will be very thankfull of you.

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    63. How this capacitor C1 reduces high volt AC to low volt AC. pls elaborate the principle behind this

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    64. Dear mohan kumar sir,i seen your designed circuit, all are working fine but i need a transformer less power supply from the two different kind of Phase supplies, with the current of 100mA and the input supply is 210v – 450v / phase, out should be 5v / 100mA .

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    65. Dear sir, Can you please let me know how to give DC power transformerless supply of 12V to IR LEDs (60+60). And also please provide me the link of the same circuit diagram. Any reply shall be highly appreciated. With Regards!

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      • C.Mitra Chinmoy Mitra says: on December 14, 2012 at 4:21 pm

        Hello Virender, the problem is that people like you want a quick and magical solution for your problems, without providing sufficient and clear information about the problem. To get a free answer to your problem, the least you can do is sit down at your computer and spend at least 10 minutes to write the details about the project. What does (60+60) mean? Is it 60 led’s in series in one group connected to another 60 led’s in series? Or is it 120 led’s in series? Or is it all 60 led’s in parallel connected in series to another 60 led’s in parallel?

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    66. pls try to clear the value of the resistor labeled 100R…is it 100R or 100K? try to be consistent in your posting..otherwise shits are the result….

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    67. i have 6v AC and 100ma input current. i want to charge cell phone or any device. i put the circuit through rectifer 1n5408 and for ripple i used 1000uf to remove ripple but i am getting 1ma current after it. i put it through voltage regulator and i am getting 5v dc voltage but i am getting enough current to charge device…any suggestion how can i improve

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    68. jayakrishnan says: on November 26, 2011 at 8:33 am

      How to drive a 12V DC relay using this circuit?

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    69. waseem ahmad says: on November 30, 2011 at 4:23 pm

      Most respected sir,
      please send me 12 volts 55 watt transformer less power supply circuit urgently
      Please guide me how yo do……

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    70. Samiuddhin says: on December 2, 2011 at 7:15 am

      Sir. I made this circuit, but after few mins resistor R3 and R4 get overheated and burn out.
      The No load voltage is 90V before the zener. So, pls help to get the output 12V 100mA.

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      • try to change higher resistor and its wattage…check also ur zener diode maybe got defective after resistor burned out…
        mke sure c1 wrking properly

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    71. it is very efficient methode.but it i used only for small outputs.

      Like or Dislike: Thumb up 0 Thumb down 0

    72. VERY GOOD

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    73. osama bin laden says: on December 25, 2011 at 8:20 pm

      I have an idea

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    74. i want a charge 6v 4.5 ah battery in a emergengy lamp so i need a transformerless power suplly to that so plz help me to do this circuit sir

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    75. i want a charge 6v 4.5 ah battery in a emergengy lamp so i need a transformerless power suplly to that so plz help me to do this circuit sir my mail adress rockzs1419@gmail.com and same adress for facebook and ph.no 9247200307

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    76. can you display the 900MHz oscillator circuit diagrm please..

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    77. good day sir, I’ve tried the experiment but it’s giving me some problems. the resistor r2 is getting burnt.pls what can i do? thanks

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    78. Hello sir,
      Actually we are using same circuit for toggling relay nd it’s working fine for normal ac supply nd for UPS…but when we provide ac supply through invertor it doesn’t work..the voltage across zener drops to 7.7V from 13.30V when ac input is through invertor.
      In our case C1 is 1uf 250v,R1=1Mohm c2=22uf 25V ,we haven’t used R3 & R2,Zener same 15V…
      what is use of R3 nd R2??
      please can anyone suggest solution as early as possible??

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    79. Hello sir,
      Actually we are using same circuit for toggling relay nd it’s working fine for normal ac supply nd for UPS…but when we provide ac supply through invertor it doesn’t work..the voltage across zener drops to 7.7V from 13.30V when ac input is through invertor.
      In our case C1 is 1uf 250v,R1=1Mohm c2=22uf 25V ,we haven’t used R3 & R2,Zener same 15V…
      what is use of R3 nd R2??
      please can anyone suggest solution as early as possible??

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    80. sir i want to charge 4v 0.4ah battery plz help me says: on January 10, 2012 at 1:06 pm

      helpful

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    81. hello sir……
      I want simple circuit for lighting 20 led (ac to dc transformer-less circuit )without using transformer
      please help me…

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    82. Mosses .A says: on January 12, 2012 at 12:17 pm

      dear sir,
      Good evening
      i need a detail about electronic mosquito repellent and circuit.
      pls do me favour sir
      thank you

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    83. hello sir
      am trying to detect AC 230V using optocoupler
      please give me any circuit idea

      and in circuit shown top above
      give me formula how to calculate R1, R1, C1

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    84. Hi Mohan

      Can you recheck the Xc = 225k value ?

      Xc= Vrms/Irms

      if Xc= 225k then Irms = 230V/225k = 0.001 A = 1mA

      C = 1/2*pi*f*Xc = 1/2*3.14*50*225k = 14nF

      Let me know

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    85. Dear Mohan,

      225K refer to 2.2uF (the 5 is number of zeros in pF so 2200000pF=2.2uF)
      in calculation:
      Xc=1/2*pi*f*c=1/2*3.14*50*2.2u=1447 Ohm
      I=V/Xc=230/1447=0.159A

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      • hello Eli T,

        by using 2.2uf can i get perfect circuit for to deliver 150ma .

        whats the output voltage of that.

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    86. On DC side, if touched, do we get shock?

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    87. Nice weblog right here! Additionally your website rather a lot up fast! What web host are you the use of? Can I get your associate link in your host? I wish my website loaded up as fast as yours lol

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    88. Gostei muito dessa fonte. Legal cara (a brazilian)

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    89. sir, individual needs/comments are knowledgeable.
      sir i have a spot billing printer(electricity bill printer) having 12 volt 1 amp baterry charger having surge protection. But these chargers are not lasting. Now i am using 12v, 400ma adapter for charging purpose. It serve the purpose but it takes 8hrs to get full charge.
      Can i have your support to built a charger of the same capacity.Or circuit diagrame.

      Thaking you

      sherab gyamtsho
      Corporate employee
      Trongsa Bhutan

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    90. md gaffar beag says: on February 24, 2012 at 5:09 pm

      sir i have a 9V transformer i want a dc voltage of 2 volt 1.5A……can you pls help me regarding this..

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    91. Duc.Chu says: on March 4, 2012 at 5:48 pm

      Dear sir ,
      I read your article for transformerless on the internet. It was very interesting, I was trying to understand it. I think it is a reduce the voltage circuit with impedance of the capacitor but I can not calculate its parameters (voltage, current). It’s better if you kindly me the formula.
      Thanks and regards.

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    92. http://www.electronicsforu.com/electronicsforu/circuitarchives/view_article.asp?sno=148&article_type=1&title=Muscular%20Stimulator&id=429…..
      In this can i use the concept for 220v-12v concept sir…
      Please Reply me as soon as possible sir..

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    93. hi
      plz give a transformer circle for convertur 220 to 12 voltage thank very much

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    94. Amer Rehman says: on March 13, 2012 at 1:56 pm
        member

      What are the benefits of using transformerless power supply, to reduce cost?

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    95. i need explanation of circuit..as early as pssble..pls..thnx..

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    96. i need explanation of circuit,,pls rpl as fst as pssbl..hv v appld both ac & dc voltg 2 the circuit,,as shwn in the fig.

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    97. Mr. Mohan Kumar
      I need a circuit which will replace the 9V battery. Is this circuit will help in that. Please …

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    98. ritesh kumar says: on March 19, 2012 at 10:39 am

      i need circuit diagram description for power supply without transformer 12v,10mA

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      • i need circuit diagram description for power supply without transformer 12v,100mA ( is R2=100 OHM,or 100k),(r3=220 ohm ,or 220K)

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    99. Sir, how i calculate the output voltage? is the value of x rated capacitor depends on output voltage?

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    100. plz sir!!!! give me the ckt of 230v AC to 9v DC without using transformer……. plzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz

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    101. can u plz provide me wth the design of the power supply wth the rating of 12 V DC and 10 mA current. Thanking you

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    102. Anil HRD says: on April 11, 2012 at 3:27 pm

      in the given ckt resistor 220r 1w is getting very very hot …. it will not work for long time and output supply also high .. around 16-17 VDC

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    103. Parmjeet Singh Parmjeet Singh says: on April 12, 2012 at 11:23 am

      sir,i need transformerless power supply circuit for 30 yellow coloured leds(5mm),can u send me circuit.

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    104. vineesh says: on June 21, 2012 at 1:44 pm

      vineesh says: June 21, 2012 at 1:43 pm 0 0
      i am an electronics enggr. just gone thru this ckt. this ckt wont last for long. the resistors ob both ac side and dc side will heat like anything. even you use 5w resistor also same effect can observe.zener also will heat like anything even use high watts zeners. if use less value caps say 0.2uf, then this ckt is very fine,but only 20ma current can deliver

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    105. chandu says: on July 7, 2012 at 7:23 pm

      I agree with Vineesh. This circuit is crap. All the resistors R1, R2 and R3 will heated up and burn off within 5 minutes. This circuit would have tested before publishing.

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    106. sushant patil says: on July 10, 2012 at 12:40 pm

      i have to know that ow transformer couple amplifier work as voltage follower ….. and gie me the aaplication of charge couple amplifier.. reply soon i am waiting for your reply

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    107. the capacitor c1 used in the circuit 2.2 mfd(225k)which is difficult to find in my nearby local market…
      my question is that can i use the ceiling fan capacitor(2.5mfd,440v) in place of c1..
      ceiling fan capacitor is available everywhere..

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    108. Can u just least all AC capacitor and give me their maximum voltage and current,,,,

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    109. Can u just least all AC capacitor and give me their maximum voltage and current, plz

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    110. scabbasrh says: on August 20, 2012 at 5:56 pm

      Hello sir
      I am Beginner .
      so i confused whats the red led

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    111. cellphone battery packs require 3.7vdc and 180ma=to=200ma current for charging.. can hi use this transformerless%power%supply as a mobile phone charger to replenishes$the cellphone -batt!”within two or three hour..as matter of fact$will current of 100ma is sufficient for charging cellphone…plz can u just help me and tell the real fact of this….thanks

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    112. [Colin mitchell] help me ooooooooooo@0ooooooooo???????????treasure

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    113. @d. mohan kumar sir can u tell me what value of dropping capacitor and c2 have to be selected in order to get 5v dc supply with 20ma current… her im giving input from supply mains 230v ac power supply(50hz)

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    114. sama nkenyi ramson says: on August 29, 2012 at 5:56 pm

      hello sir.i was very satisfy with this circuit design.thanks

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    115. sir.!!!! can u give me layout for transformerless ac to dc for fabricate it on pcb…….

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    116. Dear sir,

      i want ask you, that output is in DC??? ant can direct connect with LED??
      can i add the LED (10 LED or above)??

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    117. Sir,
      i want to make a supply for ATmega32 MCU. I need 5v input voltage which i will get using zener diode. Or using 7805 IC. But is this ckt can realy replace Step Down transformer to such a great extent that i can use it in place of that? I also want to know can i solder this ckt on a PCB? (I think it will burn…).so better to ask first….THANKS in advance and waiting for an early reply….thanks a lot

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      • Jim Keith Jim Keith says: on October 10, 2012 at 10:12 pm
          member

        This type of power source is not recommended for human interface type of equipment due to shock hazard.

        Recommended is a wall wart (outlet mounted) power adapter containing isolation /voltage matching transformer–there are 5V regulated versions available, or you can add a 7805 regulator to a 9 or 12VDC version.

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    118. @jim – thanks your valueable reply…

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    119. Can someone pls help me a circuit diagram of a battery charger that can charge 3 24 volts battery at once and maximum 6 24 volts. Having regulator to select if to charge 3 or 4 or 5 at once

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    120. sri says: on March 13, 2013 at 5:45 pm
        member

      hello sir, the above circuit diagram exactly output 4.9v , so what i replaced or change the circuit diagram please send my email address.

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    121. sri says: on March 13, 2013 at 5:52 pm
        member

      sir, i have one battery 3.7v dc 1020ma i am increase the voltage 4.9v dc so what are the elements using the increasing the voltage plz reply me.

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    122. In all probability, this is an untested & dangerous circuit. In a transformerless capacitive power supply, the output current (not voltage) is limited by the primary component-the series capacitor. As per the diagram, how it produces +12V output with a 15V zener diode? Here,I observed a chance of C2 failure (because of the “strange” R3-ZD combination, too!

      Interested readers can refer this document from Microchip http://ww1.microchip.com/downloads/en/appnotes/00954A.pdf

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      • C.Mitra C.Mitra says: on July 22, 2013 at 4:59 pm
          member

        Dear Mr.Hareendran, your comment here is quite right to some extent, and also wrong. Let me explain…

        1. As you have said, this circuit is dangerous, but to an experienced hobbyst it is as safe as safe can be! Beginners should make this under the guidance of experienced and knowledgeable experts. The completed circuit should be enclosed in a pastic container.

        2. Untested, maybe. Since the components used seem to be a bit unrealistic in value. The series capacitor is too large (2.2uF), since it has to be a polyester or paper type, rated at atleast 1000V AC.

        3. A few simple ohms law calculations shows the following facts:-
        a) The total shorted current capacity of this circuit is about 130 mA, since the capacitive reactance of a 2.2 uF condenser is 1.44 kohm at 50Hz.
        b) A zener diode of 15V across the output (with only a 220ohm dropping resistor) is absurd, since it will draw a heavy current and heat up the 220 ohm and 100 ohm resistors. Zener diodes used as shunt regulator, as in this circuit, can only provide small currents. A zener diode can not regulate a load current of 100 mA.

        3. You are right that a 12V output is not possible with a 15V zener. Yet, there can be an explanation for that too…that 15V zener may be just sitting there doing nothing, since the default output voltage itself may be 12V. So the zener is not conducting at all, and (maybe) sitting there as a safety device to limit the output voltage to 15V in case the source votage goes beyond 15V DC.

        4. This type of circuit is very common and is widely used in all chinese made rechargeable torches, lanterns, decorative lightings etc. C2 failure in these gadgets is very common where they have used ordinary polyester capacitors rated at 100V to 250V. Capacitors rated at 600-1000V never fail.

        Finally, the truth of the circuit can only be ascertained after actually assembling it and trying out. I will try to do that in the future and post the results.

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    123. duho9057 says: on June 15, 2013 at 1:12 pm
        member

      Chân thành cám ơn trang web đã có nhiều mạch điện thiết thực hữu ích.

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    124. h.i.singh says: on July 9, 2013 at 12:22 am
        member

      good site for begineers.

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    125. Hi
      I need to 24V,4A power supply circuit,
      can you help me?

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      • C.Mitra C.Mitra says: on July 22, 2013 at 5:06 pm
          member

        Dear Mary, I can help you if you provide a little more data about your requirement.
        1. Firstly, do you need a switched mode supply or ordinary transformer type supply?
        2. Do you want a regulated power supply?
        3. What is the purpose or use of the power supply? Is it audio related for powering audio amplifiers, or is it for charging lead acid batteries, or some other purpose. The use will decide the design, since the ripple content and filtration is dependant on this.

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    126. i want to convert 230v supply into 5v without transformer circuit i.e. by using only resistor and capacitor circuit

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      • It can be achieved but the voltage will not be stabilized, and the output voltage will decrease as the current consumption will increase. So you can make a circuit that outputs 12V for example then use a 7805 voltage regulator if you need a fixed voltage.

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    127. ashwini says: on August 9, 2013 at 7:25 am

      can give me any resistor,capacitor circuit idea so that
      it can be used for long time without heat dissipation

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    128. ashwini says: on August 9, 2013 at 7:30 am

      as you shown ckt diagram,it taking big capacitor.i want
      to make small and handy circuit

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    129. sir can you please explain me how to convert 230v/5A 0r 3A/50Hz to 5v DC of 20 mA….Sir please brief me operation.

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    130. sir , can plz tell, how to know how much current my circuit needs..

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    131. Dear Sir,

      I need 22v 1A transformerless power supply

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    132. Hello sir,
      I read all of the above ,but cannot understand that how to calculate or find out the different output voltage(s)to the circuit with or with out load from different x-rated capasitors of different values(uF) using on 230v AC main line in india?
      please give the calculation as I am very confused to
      select the proper x-rated capasitor for my home application?

      wating for your reply eagarly.Thanks in advance.
      MK.

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    133. Sir…
      Can i connect a 7812 IC voltage reg. instead of Zener diode..?

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    134. Digil David says: on October 16, 2013 at 8:10 pm

      Sir, what will be the output voltage of 225k capacitor series with a volt meter

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    135. We design this circuit but it’s provide heat very strongly. We changed the 220ohm resister 1W to 10w its heating was reduced but it’s still produce heat in the long run. Can you give us a diagram that heat less.

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    136. Any one please let give the either ic no or circuit diagram, which convert high volt dc to low volt dc

      ex: 30v dc to 9v dc

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    137. MUHAMMAD ZAIN UL ABIDIN says: on November 23, 2013 at 6:49 am

      sir i want to make transformerless power supply with 100 watt at the output plz suggest the values of capacitors.

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    138. nil agrawal says: on December 3, 2013 at 6:41 pm

      it help so many persons to change their know how

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    139. I want to know the safety of the transformerless circuit.
      thanks

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    140. For safety, the low side must tie to the power distribution neutral line, all electrical outlets used must be polarized correctly and the distribution system must be connected and grounded properly. For me, this is a little too much to depend upon.

      Frankly, I’m surprised that we do not hear horror stories associated with this type of power supply. I take this back, because the old series string electron tube radio sets used this trick back in the 1950′s — and I received nasty shocks from them. Subsequently, they added a ‘protection’ circuit that isolated the chassis from the power supply via a parallel RC arrangement that limited ground fault current to an uncomfortable 5mA. (got them through UL approvals anyway)…

      I, for one, do not recommend it and suggest that experimenters use wall wart power supplies instead of this potentially dangerous power source. Over the course of time I have collected a box of them and it is rare that one does not fit the reguirements. Check out this post:
      http://www.electroschematics.com/6938/of-wall-warts-wall-transformers/

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    141. In this circuit how can vary output voltage and Current? What component determine o/p voltage and current?

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    142. hi sir..
      can i use this ps for driving knight rider circuit using 555 and 4017,what will happen if i replace lower wattage zener

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    143. D.M.Gharat says: on April 13, 2014 at 5:44 pm

      pl. provide me the 230ac to 48 vdc transformerless circuit

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