Simple 100W inverter circuit


Here is the circuit diagram of a simple 100 watt inverter using IC CD4047 and MOSFET IRF540. The circuit is simple low cost and can be even assembled on a veroboard.

CD 4047 is a low power CMOS astable/monostable multivibrator IC. Here it is wired as an astable multivibrator producing two pulse  trains of 0.01s which are 180 degree out of phase at the pins 10 and 11 of the IC. Pin 10 is connected to the gate of Q1 and pin 11 is connected to the gate of Q2. Resistors R3 and R4 prevents the loading of the IC by the respective MOSFETs. When pin 10 is high Q1 conducts and  current flows through the upper half of the transformer primary which accounts for the positive half of the output AC voltage. When pin 11 is high Q2 conducts and  current flows through the lower half of the transformer primary in opposite direction and it accounts for the negative half of the output AC voltage.

Circuit diagram.


  • B1 can be  a 12V/ 6Ah lead acid battery.
  • Q1 and Q2 must be fitted to a proper heat sink.
  • T1 can be a 9-0-9 V primary, 230V secondary, 150VA transformer .
  • Do not expect much from this circuit. The is very simple one suitable for low grade applications.
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210 Responses to “Simple 100W inverter circuit”

  • Ramesh says:

    Sir what happens if i use 12v 10aAh battery to this circuit.and pls tell me how to increase output power of this circuit pls……………..

  • Ramesh says:

    I like very much this website. sir will you please tell me what is the function of mosfets in this circuit.pls give me answer urgent

  • Jamey says:

    Is there any way I can show 12v AC output from this circuit without connecting the transformer? My project supervisor is not allowing me to use transformer at all for safety reasons, so I can’t show him 12V AC. He just wants me to show him inverted 12V ac output. Please help me with this. Tell me what I need to add to this circuit instead of a transformer to show 12V AC output, please explain the procedure. Your help will be gratefully appreciated

    • Seetharaman says:

      Use 1 K ohms 1/2 watt resistances in place of transformer winding and show either on AC range of a multimeter or on an oscilloscope (ofcourse measuring across the resistances.

  • jeo shaji says:


    Here is the circuit diagram of a simple 100 watt inverter using IC CD4047 and MOSFET IRF540. The circuit is simple low cost and can be even assembled on a veroboard.

    CD 4047 is a low power CMOS astable/monostable multivibrator IC. Here it is wired as an astable multivibrator producing two pulse trains of 0.01s which are 180 degree out of phase at the pins 10 and 11 of the IC. Pin 10 is connected to the gate of Q1 and pin 11 is connected to the gate of Q2. Resistors R3 and R4 prevents the loading of the IC by the respective MOSFETs. When pin 10 is high Q1 conducts and current flows through the upper half of the transformer primary which accounts for the positive half of the output AC voltage. When pin 11 is high Q2 conducts and current flows through the lower half of the transformer primary in opposite direction and it accounts for the negative half of the output AC voltage.

    Circuit diagram.

    ◾B1 can be a 12V/ 6Ah lead acid battery.
    ◾Q1 and Q2 must be fitted to a proper heat sink.
    ◾T1 can be a 9-0-9 V primary, 230V secondary, 150VA

  • Jamey says:

    I tried connecting the transformer with inverter and got 230V output. Can you please tell me why the mosfets don’t show any output without connection of transformer? My supervisor for my project asked me to answer this,and I don’t have any clue about it. Please explain in details

  • Jamey says:

    In which software can I try the simulation of this circuit diagram?

  • Jamey says:

    Can I use 1µF 450V 105°C Radial Electrolytic Capacitor instead of the 600V one?

  • Jamey says:

    i tried this circuit upto the transformer, it doesn’t show 12V AC! What might be wrong with my circuit?

    • Jamey says:

      It shows something like 0.25V AC

      • Seetharaman says:

        Both the MOSFET are alternately switched on use a scope across one of the primary windings. with a multimeter on AC range measure at the transformer secondary for 230 volts. If not check the 4047 circuit fo proper oscillation at 50 Hz check with a frequency meter.

        • Jamey says:

          I did not understand the part ‘use a scope across one of the primary windings’ !
          I haven’t connected any transformer yet,I wanted to make sure the output from the inverter without transformer is 12V AC first, cause 12v DC from battery should be inverted to 12V ac,but its showing only 0.25!

          • Jamey says:

            Is there any other alternative to not using the 0.1uF 600V capacitor in the transformer section, cause its risky and my university is not allowing me to order it. I bought the transformer though

          • Seetharaman says:

            Trough the transformer alone the MOSFETS are getting the supply without connect it you will never get any output at its Drain as it becomes an open drain circuit.

    • Jamey says:

      Any alternative to the 0.1uF 600V rated capacitor? In our university lab, we only have capacitors of 25V capacity!

      • Seetharaman says:

        Hi Jamey you have to use 450V DC or 250 Volts AC capacitor only. Without transformer connected no supply is fed to the MOSFET drains, you will not get any amplification hence no output. You can try with a load resistance also for the MOSFETs, without transformer on an oscilloscope the square waveform will appear.

  • Khurram says:

    Seetharaman,Tell me the purpose of C4, what I think it shouldn’t place in parallel on out because it will short the output. In D.C we can use decoupling capacitor but in A.C if u use it in same fashion through capacitor C4 all the voltage will sink to the ground through it & output will become zero.

    • Seetharaman says:

      Hi you are right but here the value is very low and it is used for smoothing the sharp edges of square wave output of the inverter. Such that the square wave edges will get rounded, the harmonic output also will get reduced

  • NILANJAN ROY says:

    sir is it can drive a mobile charger or adapter of 150-300vac , 50-60hz 0.15A

  • Jamey says:

    How can I make a battery charger circuit and switch circuit for this inverter? How would the all the circuits be connected together? I want that when my main AC power fails,the inverter switches on automatically. Is the relay work for this included in the switch circuit? Please help me out.

  • Chandrashekhar says:

    Sir i try the 100w inverter ckt it gives 220v ac but when i put a cfl to the output the voltage becomes very low about 85v. Please sir tell me the solution.

  • Jamey says:

    How can I make a complete UPS circuit from this inverter? I think I need relays and a switch circuit, how do I connect them? please help

  • kiran says:

    hai sir i checked in ur
    100w inverter ckt its
    working .but i have
    one small
    problem.when i give
    the load to ckt that
    time the vge will be
    reduced . example i
    give 20w cfl to load
    that time the o/p
    power reduced to
    20v . so pls give the
    correct solution. my cell number 8088394449 please help me

  • okoye says:

    what is capacitor c2 rating?

  • Akeem says:

    i want you to specify me the type of IR driver cct to trigger Mosfet power cct in order to give me 5KVA single phase inverter

  • Nitu says:

    Can i use 12v transformer

  • okoye says:

    is capacitor c2 a polarity capacitor or non polar?is q1 and q2 mounted on the same heat sink?

  • okoye says:

    what type of capacitor c2 are my going to used and the transformer details.

  • pranjal says:

    I am unable to find IC CD 4047 in eagle software

  • pranjal says:

    Dear Sir, please give me eagle pcb layout design for the 100w inverter. I want to make that on copper laminated pcb.


  • cyril says:

    sir what transformer should i use.

  • Santhosh kumar says:

    Sir i done this project. It was working good. but i want to known about the ic 4047 internal constuction how it is giving 180 degrees phase shift pleace it is urgent am doing this my miniproject so i want to give seminar plz sir

  • santhosh says:

    sir circuit was working………i want internal structure of 4047 ic ………..plz sir….

  • pradeep says:

    hello sir u r using 0.1microfara 600v….. but we know that capacitor can blocks ac…… how we r expecting 230v ac

  • Grousselas says:


    I do not practice English fluently so I am forced to use online translation .
    I am a modest French electronics and retired for 4 years , I have invested in renewable energy for personal use (2.5 KW Photovoltaic and wind)
    Everything works fine . But less than 4 years , 2 3 KW inverters sine did not take the road as unreliable.
    I decided not to buy expensive and impossible to repair converters. So for almost a year , I’m looking for a solution to build a converter 3 KW .
    Currently , I experimented with a 555 + SA 4017 CD . Power mosfets IRFP 250/ 260 IRFP . The transformer is a 3 KVA new. Several mosfets are connected in parallel when the development will be effective .
    The result is insignificant. Look here:

    Do you think the use of CD 4047 will improve the power expected .
    What is the width of the pulses delivered by the 4047 CD , compared with the 4017 CD ?
    Watch here the draft very temporary mounting with a 120 W lamp that lights the secondary half . 120 volts measured with a digital controller.
    If you wish, thank you to tell me what you think.


  • sandy says:

    for inverters and solar projects

  • Viques says:

    What is the function of that POT?.and is the transformer a normal one or do i hv to use a center tapped one?…i’m asking this cuz i’m having 3 wires in my transformer n i knw one handles 110V..wont it smoke up the shit?!

    • Seetharaman says:

      i Viques it is to set the frequency of oscillation to 50 or 60Hz. You have to use 230 to 9V-0-9V center tapped transformer, use by interchanging primary and secondary.

  • peter k ngeno says:

    what is rate of the transformer used

  • I wanted To Know Whether This Circuit Diagram Is Correct And Do It Work Properly ???
    Sry To Say That Because i Really Want To Make That Inverter So A Bit Serious About It..

  • rajesh says:

    hai sir i used in 12v 7ah battery , 12v/2amp transformer and 9v/1amp heavy transformer its not suited for the 100w inverter.
    Its not suit pls say how to increase the power .

  • rajesh says:

    hai sir i checked in ur
    100w inverter ckt its
    working .but i have
    one small
    problem.when i give
    the load to ckt that
    time the vge will be
    reduced . example i
    give 20w cfl to load
    that time the o/p
    power reduced to
    180v . so pls give the
    correct solution.

    • Seetharaman says:

      Hi Rajesh it may be the quality of inverter transformer, its rating or the 12 volt power supply is not capable of providing the required current.

      • manikanth says:

        if we increase the battery ah ,can the ckt is destroy or not?

        • Seetharaman says:

          Hi Manikanth if you increase the AH of the battery the inverter will work for a longer duration. say if you use a 12 volt 7AH battery for this inverter you will get the inverter going for 45 minutes if your load is 100VA. if you use a fully charged 12 volt 40AH battery it will work for 4 1/2 hours without needing for recharge for the same load.

    • Do It Really Works Mr Rajesh ??

  • rajesh says:

    hai sir i checked in ur 100w inverter ckt its working .but i have one small problem.when i give the load to ckt that time the vge will be reduced . example i give 20w cfl to load that time the o/p power reduced to 180v . so pls give the correct solution.

  • Devendra kurmi says:

    Hi, in this circuit I did not find C1 capacitor. Is it missing?

    Do you have any better circuits. Does this circuit works directly on solar panel?

  • a.maharajan says:

    c2 capacitor 0.01 micro fared howmany voltage?

  • sanaullah says:

    Hello sir ! the circuit is not working …….. :(

  • Ahmar says:

    what is the wattage for resistors?

  • sushil says:

    why it is used R6 1k pot. ? what
    will b problem in using of 1k
    resistor instead of that pot. ?

  • sushil says:

    why it is used R6 1k pot. ? what will b problem in using of 1k resistor instead of that pot. ?


    the wattage of resistances are not mention.

  • hadi says:

    hello sir i need 250 watt inverter plz help meee.

  • sanaullah says:

    it does not work!!!!!!!!!!

  • wasimakram says:

    Hello sir I want to make a helecoptor with remote please sent me thank u

  • WAKHEEL says:

    Hello. plz i need of components equivalent DATA.

  • WAKHEEL says:

    Plz . I need component equivalent data

  • Azeez says:

    Hello sir i need 200w inverter circuit…so can u help me?

  • deva prakasam says:

    dear sir/madam, Is there any controversial between astable multivibrator and mono,bistable according to thier application. answer me

  • chinna says:

    hello sir!
    Here we are using ic4047 as astable or monostable multivibrator.Can we replace with 555 timer.please reply me sir

    • Anish says:

      555 timer has only one output. But 4047 has two outputs which are compliment to each other. Similar to a flip-flop. Moreover, conversions like this – DC to AC, AC to DC etc has more power loss. 4047 is a CMOS IC and hence consumes very low power compared to the TTL 555 timer. Any way the obvious reason may be the two kinds of o/p offered by 4047 and also, it uses minimal external components than 555.

  • chinna says:

    hi sir! can we connet 230v ac to bulbs or fans

  • gokul says:

    this circuit is work good but the battery is only use 7ah is used or increase the battery level….

  • stephin says:

    hi sir
    Which type of transformer i need to use for this circuit 9-0-9vAC primary or DC primary?please reply anyone..
    .can i use this for running my 21″ CRT monitor tv?

    • rohin says:

      hi, you can use normal transformer which in E,I core.transformer always works on ac can use 9-0-9 ac transformer with 10 amp.if your monitor wattage is less than 100 w than you can use this circuit.transformer can work both sides if you give input 220 v ac than it become step down 9-0-9 ac and if you give this side 9-0-9 ac then it can give us 220v ac and called step up same transformer can work both things.

  • stephin says:

    hi sir
    whch type of the transformer can i use for this circuit,both the primary and secondary should be in AC?
    I need to run my 21″ CRT monitor tv by using this circuit ,do i ?please reply…..

  • Ankita kanekar says:

    can i use IRF540 mosfet to design 3 phase inverter ckt for controlling BLDC motor.? plz help what is the specification of this mosfet?



  • mahi says:

    Hello sir, I also have 12-0-12v/230, 7A transformer.
    Will I use it to this circuit? plz help

  • kranthi says:

    This circuit is good for implementation

  • Vinod says:

    Hi, This is very good circuit. Do i need a special transformer for this?, What if i connect an ordinary 9-0-9 1A transformer ?.Please help.

  • vinay says:

    hello, i am new to electronics ,this circuit inspired me a lot, so i wanted to try it, but the capacitor c4 of 0.1uf/600volts is not available for me…so tell me any alternate..and by connecting the capacitors in parallel the capacitance can be added no,so can i try in that way……?m plz give ma a solution for that…….!

  • cheralathan says:

    i want to buy an ic cd4047 in villupuram the ic does not pls send store name in pondy,or cuddalor.

  • jafar says:


  • jafar says:



    Is this inverter suited for 40w ac soldering iron?

  • chandrasekar says:

    dear Mr. govindasamy
    IC 4047 is easily available one. In madurai(Tamilnadu) it costs only Rs.18. so try to your nearer big city electronic market.

  • FASIH says:

    hello sir i have constructed your circuit on proteus but all i am having is a 0V AC output…. please if u think that there might be some mistake let me know. i am using a simple 12V DC battery

  • govindasami says:

    i need the ecavelent ic to use of cd 4047

  • chandrasekar says:

    In this circuit the transistors IRF 540 getting tooo much heat within seconds and Im not getting output. I use 12-0-12. 3A transformer.
    what is the problem?

  • chandrasekar says:

    when the circuit connected to AC is the battery tobe charge automatically? or we charge from extra source?

    • siraj says:

      hi chandrasekar!! you asked a question about the charging prob. right the same question too rised for me!! i have post the comment, no reply for that!! did you got the answer from or you got help from others? if so pls reply for me!!!

  • deepak seth says:

    and how can we control the speed of 90 watt motor with this inverter circuit?

  • deepak seth says:

    sir, for a 90 watt, single phase motor will this circuit be appropriate ? or can u suggest some other circuit.

    kindly suggest something for 0.5 hp motor.220 volts. single phase input.

  • Anusha says:

    Hi sir.. actualy i m getting the output as 82v at secondary of the transformer.I checked all the pins then i came to know that voltage is getting droped at 4th pin there by m not getting voltage at 11th pin so the second mosfet is nt conductng completely where m gettng only 4.35v at primary of transformer connected to drain and center tap where in for first mosfet m gettng 9v.. so what would be the mistake..??

  • what is the minimum current rating of transformer.???

  • Can You Show me How that Transformer looks like???

  • Allwin M.A. says:

    Hi sir,
    How can i calculate the efficiency and power factor of this circuit ?
    Is power elctronic circuits depends on power factor ?

  • Charles John says:

    Good job.

  • Seetharaman says:

    Hi Nithin the transformer should be rated for 9-0-9 volt at 150VA. Use standard polyester or ceramic disc capacitor rated for 25 to 100volt 103 for C2 and 104 / 600 volt polyester for C4. What you have indicated some imported non standard capacitors their values will not be as you expect. Kindly nuse standard CTR / philips etc

  • Can you please tell the current rating of the transformer…….

  • i used a 103M 2 KV for C2 and 01M 1KV for C4 will this affects the working of inverter…and can a regulated dc dual rail be used instead of a battery??

  • what kind of load will work in this inverter…..
    i used 9-0-9 500mA transformer …MOSFETS and transformers are heating enough but there is no output …
    will we get shock if we touch the o/p wire…??

  • Seetharaman says:

    HI Nithin you can use 1N4001, Preset to fix the inverter frequency at 50 or 60Hz, With the rcommended battery 30 minutes approximately.
    Hi Avinash you can get the current flow with respect to one wire in the other, hence both the wires are required. if you say that line tester is glowing on both wires(it will sinece the secondary of the transformer is floating) if you want to avoid this, you ground one wire of the secondary.

  • avinash says:

    Sir plz tell me
    out put of inverter ac volt come in both wire but i want to taking in one wire face in full 220vac what can i chang in

  • avinash says:

    Sir plz tell me when the out put of the inverter ac volt come in both wire …but i am taking i on. Wire what can i add/change in……plz

  • what about the Duration of load(time)
    What is the function of the preset

  • Nithin Pradeep says:

    Can IN4001 be used instead of 4007
    Is this circuit capable of driving a TV load …
    pls reply…

  • Umar garanzoi says:

    Sir, i want to build a circuit may i use IRFZ44N OR IRFZ46n insted of IRF540, Can it work. Also how to increase it to 500W?

  • Seetharaman says:

    Hi Sunil use 250volt tap, if available in the transformer. Hope the transformer used is 96VA rating. If taps are not available you can use a 230V/24volt 24VA transformer and step-up the voltage.(Like a step voltage regulator)

  • sunil says:

    i used 12-0-12/230 96A transformer the output voltage of the inverter is 210vac.

    what transformer do i ned to use in the circuit for 230vac output?

    please help……..

  • lin says:

    Thanks for this circuit and its working great…
    Could I increase the watts of this inverter by modifying this circuit?
    Please help me.


  • GREAT ATA says:

    Describe c2 fully (what is the voltage) and the size of all resistors

    • admin says:

      C2 can be a general purpose ceramic disc capacitor (they are generally available with a voltage rating around 1KV and it is well enough)
      All resistors can be 1/4W metal film or carbon film.

  • Leliance says:


    I am totally new to electronic but I have always been looking to make my own inverter circuit. Its just for fun or for my understanding purpose, I wonder if someone out here can guide me or share me their circuits. Basically, I’m not looking to generate lots of energy from 12v battery, I need a circuit which invert 1.5v/3v to some higher range.

    Write back to me if anyone can help. Thanx in advance.

  • Seetharaman says:

    Hi Kirthik your transformer should be low loss type. If you want 45 watts out put say at PF 0.8 then the VA at secondary should be 56VA and if the transformer efficiency is say 80% then the primary side requirement is around 70VA with 12 volt supply the requirement is 6 amps approximately. Your transformer should be for a primary of 10.8-0-10.8Volt and with a rating of 70 VA. Secondary should be rated for 230 volts. (a torroidal transformer will be a better choice)

  • Athish kirthik says:

    Dear Friends,

    I did the same circuit with the 2n3055 power transistor instead of IRF540 and i have used 12-0-12 ,3A transformer , so in this case , maximum how much Watts(W)i can able to consume from the transformer , that too even if i setted the frequency to 50 Hz at that time trafo output was 233V but after connecting the 15W CFl voltage came to 96 V, but if i am increasing the frequency to 300Hz then the voltage was around 172V AC ,i want to take min of 45 Watts output so what should be the rating of transformer???

  • Seetharaman says:

    Hi Santhosh you have to have a charger circuit similar to the one used in our emergency lamp

  • santhosh says:


  • Seetharaman says:

    Venkatesh you try one of the following MTP50P03HDL IRFZ44N, K2608 MOSFET, IRF1010E, IRF740 or any enhansment mosfet of 50amps 30volts ratings. you may contact texonic instruments for your requirement.

  • venkatesh says:

    Thank You Sir.,

    My Another Question, This is not related in this circuit , But i want your help., My Numaric 600 VA UPS in problem., MOSFET 85T03GP Not available.,
    Any other substitute for this mosfet?
    Pls give the Number pls thank you., sir

  • Seetharaman says:

    Hi Kiran this cannot be converted.
    Hi Venkatesh it can be anything 16 volts or above.

  • Seetharaman says:

    Hi Venkatesh This cannot be converted.

  • Venkatesh says:

    Sir What is the Voltage value of c2 0.01uf?

  • kiran says:

    sir can this be turned to pure sine wave inverter?and what is the ampere of the transformer to get 100watt?

  • Aditya says:

    sir.. today i have done this expt. with all u said equipments… its cost i payed 200rs…. so i made connections when i given 12v dc supply to it then the capacitor which is placed near power supply (c3 2200/25v) it got burned… can u tell me why this happened….?? connections was accurate… sir plz reply soon…

  • Prince kumar says:

    How will we the battery charge?

  • Akash Ali says:

    Thank u soo much sir 4 giving me this precious reply… :)

  • Seetharaman says:

    Hi Ali the battery capacity is given by 12 X 7AH that is 84VAH. say you draw 30 watts with 0.8PF and 85% inverter efficiency. The VA requirement will be 44VA. dividing the capacity with this value you will get the maximum operation duration of new fully charged battery. 84VAH / 44VA = 1.909H, that is 1hr and 55minutes.

  • Akash Ali says:

    Hi sir… So nice circuit but i want to ask one thing that how many time battery of 12 V (7Ah) will spend if the load is 30 watt… And whats the formula to find spending time according to load……?

  • Nuhu Chiduo says:

    Hi friends,how can i get an IC CD4047 in Multism NI circuits 11?

  • Seetharaman says:

    Hi Gopal check the output of IC1 at Pin 10 & 11. If OK. Check the pin details of Q1 & Q2

  • gopal says:

    i have implemented this ckt but i am not getting out put. i check out all the connection, pls suggest where is thechances of mistake……

  • Seetharaman says:

    Hi Ganesan use the battery charger circuits appeared as our earlier project. You can use the following link or
    Hi Taimur you can use, the unit will run for a longer duration. You have to use a suitable charger to charge the battery.
    Hi Vikram you have to use 10.8 – 0 – 10.8 volt transformer.

  • simarpreet says:

    can i use 12-0-12 /220v AND 500 ma transformer in this circuit and 6v , 4AH BATTERY? WILL IT WORK ?
    please help.

  • ganesan says:

    hi friends…i have few doubt on inverter…that i given below.. to recharge the battery?

    2.rectifier circuit need for recharge the battery?

    plz help me friends

  • Taimur says:

    What If instead of 12V 6Ah battery, I use a 12V 12Ah battery ? What would be its affect? can anyone please tell me about it? If its safe so I may use 12V 12AH battery instead

  • vikram says:

    i used 12-0-12/230 96A transformer the output voltage of the inverter is 210vac.

    what transformer do i ned to use in the circuit for 230vac output?

    please help……..

  • kiran says:

    dear sir,
    Can i use this circuit to switch on a 29 inch TV[not LCD a normal one] and what will be the backup?and what type of transformer should i use.

    from kiran

  • Suman says:

    This circuit is fine.
    But may we use it to drive 200W load by using 220VA transformer?

  • Suman says:

    This circuit is ok.
    But may we use it for 200W load with a 220VA transformer? Your kind help needed.

  • Udhaya says:

    i would like to do this inverter. but before that i would like to whether it is a pure sine wave inverter or square wave inverter.
    thanks in advance

  • raja says:

    where can i get all parts of 40w inverter.
    sugest can i get this circuit board in market.
    am in chennai (tamilnadu, india)


  • john says:

    hi, can i ask? how many ampere transformer did we need to produced 100watt for load?tnx for the follow up this question..

  • john says:

    hi sir, thank u for sharing this ideas, looking forward for the positive output, thank u again, GOD BLESS ^^

  • john says:

    hi sir, thank u for sharing this ideas, i have`nt try it yet, but looking forward for the positive output, thank u again, GOD BLESS ^^

  • seetharaman says:

    Hi Haidar use minimum 120VA transformer for 100 watts load.

  • haidar says:

    hi seetharaman,im already build this inverter using 12-0-12/12va at can run 40w bulb but when i use 100w bulb it not run. should i change the transformer rating?

    -tq very much for your advice sir :)

  • Seetharaman says:

    Hi Haidar the harmonics are taken care by the output filter capacitor C4 you can increase it to 0.47uF 630V AC. This is sufficient to take care of all harmonics hence can be used with computer, Solid state TV etc (sensitive electronic gadgets)

  • haidar says:

    hi seetharaman, this circuit can run tv?
    and how to reduce harmonic?

  • seetharaman says:

    Hi Haidar all resistances can e 1/4 watt. You can use 9-0-9 75 VA transformer you will get higher voltage with low loads and at rated load it will be alright. 11-0-11 120VA is the transformer which suits better.
    Hi Azrin you can use 12-0-12 but output voltage will be around 200volts with 230V secondary winding and with 250V winding the output will be 220volts.

  • haidar says:

    hi seetharaman ,i have 2 question

    1) can i use 1watt for each resistor
    2)can i use transformer 9-0-9/230 , 75va

  • gopi says:

    hi sir,can i use transformer 12-0-12/230,75VA?
    hence what wattage i will get?

  • azrin says:

    one more question.. what transformer that u used ? and can i use 12v-0-12v transformer ?

  • azrin says:

    can this inverter turn on a TV,amplifier or fans ??

  • seetharaman says:

    Hi Kannan use the same inverter output for 3nos 23watts CFL lamps.



    plese snd me 3 cfl inverter circuet diagram

  • shajan says:

    i want inverter full circuit with chaeger

  • k t jayaprakash says:

    Dear sir,
    Please send me 3 cfl inverter circuit diagram
    Thanking you,
    Yours faithfully,

  • PrataP says:

    Can you send the exact circuit diagram and its components list to my mail… Thanks

  • seetharaman says:

    hi patil around inr500 including transformer.

  • how much amount required for this project except 12v battery.

  • seetharaman says:

    Hi Nihar with a MOSFET transistor as their switch on resistance are quite low you can can use 12-0-12 transformer the right choice. dont use 9-0-9 transformer with MOSFET. use recommended transistors for 9-0-9 transformer use.

  • nihar kanta says:

    i have a 9-0-9 transformer from an old u.p.s .when i connect the transformer to the mosfet ,the mosfet becomes hot at no load condition ,output is 280 volt,when battery voltage decreases it works properly.i changed the transformer to 12-0-12 ,mosfets are not heating, the output is 220 volt .this is suitable.please tell me how can i use the 9-0-9 transformer safely . thanks in advance..

  • seetharaman says:

    Hi Dev with 9-0-9 you will get an output of 270volts with fully charged battery, if this is acceptable you can proceed.

  • dev says:

    can i use primary 230v,secondary 9-0-9,10Amp transformer

  • user says:

    I in a quickly way have drawn the scheme. To whom it is interesting… To this address – of a photo, a file with expansion lay- i will send on mail.

  • seetharaman says:

    Hi Zafar it should be around 8 to 10Amps for 100watts with fully charged battery. with 12 volt 7AH battery it will supply for 30mts.

  • zafar iftikhar says:

    plz tell me that how much current the input 12 volt battery should produce?

  • Ankush says:

    i am not getting out of this circuit… shud i get the output??

  • Please i want to design a 1.5Kva inverter i can i go about it please i need ur help it’s for my final year project or better still a 1.5kva ups

  • vipin says:

    is this a working inverter’s circuit diagram

  • Seetharaman says:

    This is a squarewave inverter

  • Rachit says:

    also tell me how to categorise it , a sine wave inverter or some other .

  • Rachit says:

    hi, i have made this circuit at the pcb board(holed).
    the current is passing through IC but there isnt any output at secondry winding of transformer . even that ihave checked the ckt. thrice and there isnt any mistake in connections . none of the joints is loose and each of them have been soldered. also please let me know an alternate transformer (with its current and voltage ratings) that can be used in same citcuit without alterations.please respond soon .also please send me its block diagram, would be really helpfull.

  • Seetharaman says:

    Hi Neo the battery voltage is switched on alternately to the primary of the transformer. The switching device is MOSFET the drop across them is negligible hence full battery voltage will be available across primary winding. if the transformer is 9 volt with 9 volt output will be 230volt square wave if it is 12 volt you will have 33% higher voltage at the output. without load you will get around 300 volt square wave.

  • neo says:

    Hi, I don’t know much about power electronics. I build this circuit with 9-0-9 v primary and 230 v secondary (115-0-115)transformer.
    I get output 240 v at secondary when I connect center tap of primary to 11 v and much higher when connected to 12 v. what is this relationship, is there a formula that I can use to work out what voltage center tap should be connected for this type of transformer.

  • Seetharaman says:

    Hi Sankalp CD4047 is a CMOS IC iy can give an output of around 1mA which is not sufficient to drive the transformer directly, hence you require transistor take care of the high current drive to the transformer. The MOSFETs used are enhancement type they require bias to conduct. These devices require voltage drive ( around 2.5 to 4 volt)with very little current. cmos IC can take care of this.

  • Sankalp says:

    Hey, I tried to build that circuit. It’s the same problem again. Getting output pulses from the CD4047 IC but ultimately, getting nothing at the end…

    and can anyone explain to me the working of the mosfets? I mean if i’m getting 23V AC from the 4047, Why not just connect it to the transformer directly??

  • Jane says:

    anyone here can make a circuit 1.5V input and the output is 9V 1Ampere. Tnx a lot!

  • vani says:

    how many types of inverter are there?
    what is the use of mosfet in the inverter circuit and explain about its working?

  • rizwan says:

    lp-100g i need data book

  • m.rizwan says:

    iam a problem in inverter LP-100G 15HP chaingae(company) i wanna to compelet information about it plz reply me as soon as possible…..

  • neo says:

    Thxs VYSakh for ur reply, checked the mosfets pin connection, its not that.
    I even checked mosfets on thier own with 12v input to gate with source grounded but got no output at the load at drain ?

  • vysakh says:

    check mosfet pin connections :)

  • neo says:

    Hi, tried to build this circuit on breadboard, got output pulses from cd 4047 but not from mosfets. They are not switching on and off, any clues

  • darren says:

    Hi Seetharaman,tnx for ur quick responsed,i appreciate it so much,for this i gained more info on how your circuits work!!tnx for the additonal websites,,now i am searching parts,first for the transformer for this project.tnx GODBLESS.

  • Seetharaman says:

    Hi Darren you have to take saturation voltage of the final power transistor at 5 amps say it is 2 volt you require a 12 – 2 = 10 volt transformer (10-0-10). if you use 12 volt you will get 10 to 15% less out put voltage, if that is ok you can go ahead..

  • Seetharaman says:

    Hi Darren you can use 2nos mosfets in parallel or even more. you may have to add a driver transistor in between. Something similar to the following circuit

  • darren says:

    hi Seetharaman,definitely i can use more higher mosfet ryt?is it ok to use 6amp transformer?if not available 9-0-9,can i use 12-0-12 centertap x’former??..tnx.i need this circuit soon…GODBLESS

  • noufal p says:

    i want to know more about this inverter…..pls forward me a block diagram and detailed writeup…

  • Seetharaman says:

    Hi Shashi One ceiling fan say 48″ it will consume 90watts, two CFL 18 watts so total requirement is 108watts say inverter efficiency is 85%. Then the primary requirement is 108 / 0.8 = 135VA if the battery voltage is 12 then the current requirement will be 11.25Amp. your battery capacity is 7AH so if draw 7amps it will supply for 1hr approx so if you draw 11.25 amps the battery can supply for 35 minutes. hence your back up will be for appoximately 35minutes

  • Shashi says:

    Plz give it’s Backup Details with 12v, 7Ah battery with using one ceiling fan & two cfl bulbs of 9 watts each.

  • seetharaman says:

    Hi Pravpa you can use the standard step down transformers for stepping up no need for any special type.

  • pravpa says:

    a normal transformer which we use for power supply can it be used reserved side or need spl. type transformer for inverters, please explain..

  • sattv says:

    from the old uninterruptible power supply.

  • adnan says:

    is the 9-0-9v 8.5amp transformer is best or the 17amp??

  • seetharaman says:

    Hi Adnan 150 / 9 = 17amps total each 9 volt winding should be capable of 8.5amps

    • guhan says:

      hi sir thanks for sharing the projects…i have done this project and it has worked…and to the visitors….use 9-0-9 tranformer and the ampere should be 2 and above….

  • adnan says:

    9-0-9v at 150va tell me how much ampere of transformer will required?

  • vysakhan says:

    khan, its a sqre wave
    max provide 100w load

  • adnan says:

    on 100 watts load how much backup time will the battery give?

  • adnan says:

    9-0-9V,150VA transformer
    how much ampere of transformer please tell me?

  • vimal says:

    it is use for 2 fan & one tube light plz tell me

  • Please tell me its output wave, sine,square or other ???