100 Watt inverter circuit

100 Watt Inverter


Here is a 100 Watt inverter circuit using minimum number of components.I think it is quite difficult to make a decent one like this with further less components.Here we use CD 4047 IC from Texas Instruments for generating the 100 Hz  pulses  and four 2N3055 transistors for driving the load.

The IC1 Cd4047 wired as an astable multivibrator produces two 180 degree out of phase 100 Hz pulse trains.These pulse trains are  preamplifed by the two TIP122 transistors.The outputs of the TIP 122 transistors are amplified by four 2N 3055 transistors (two transistors for each half cycle) to drive the inverter transformer.The 220V AC will be available at the secondary of the transformer.Nothing complex just the elementary inverter principle and the circuit works great for small loads like a few bulbs or fans.If you need just a low cost inverter in the region of 100 W,then this is the best.

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Inverter Circuit Diagram with Parts List.

Inverter Circuit

100 Watt Inverter Circuit Diagram


  • A 12 V car battery can be used as the 12V source.
  • Use the POT R1 to set the output frequency to50Hz.
  • For the transformer get a 9-0-9 V , 10A step down transformer.But here the 9-0-9 V winding will be the primary and 220V winding will be the secondary.
  • If you could not get a 10A rated transformer , don’t worry a 5A one will be just enough. But the allowed out put power will be reduced to 60W.
  • Use a 10 A fuse in series with the battery as shown in circuit.
  • Mount the IC on an IC holder.
  • Remember,this circuit is nothing when compared to advanced PWM inverters.This is a low cost circuit meant for low scale applications.

Inverter Design Tips.

The maximum allowed output power of an inverter depends on two factors.The maximum current rating of the transformer primary and the current rating of the driving transistors.

For example ,to get a 100 Watt output using 12 V car battery the primary current will be ~8A ,(100/12) because P=VxI.So the primary of transformer must be rated above 8A.

Also here ,each final driver transistors must be rated above 4A. Here two will be conducting parallel in each half cycle, so I=8/2 = 4A .

These are only rough calculations and enough for this circuit.

We have more Inverter Circuits that you may like to read and understand;

1. How to make an Inverter

2. Simple 100 Watt Inverter

3. 60 Watt Inverter using Transistors


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229 Responses to “100 Watt inverter circuit”

  • ogunkunle kehinde says:

    pls, help me out. i want learn more about inverter. if i want to produce 1000w, how do i do it?

  • praveen says:

    Sir I tried this inverter design but I am not getting the required output. I am getting only 18Vac. Also after few seconds the 5 watt resistor(r7)(only that) begins to heat up and burn. Any ideas what could possibly have gone wrong.

  • luffy says:

    Sir need help. I had already done with the circuit but my output are not stable. My output voltage is only 40Vac and my frequency is very high. I want to set my inverter to 60hz but my minimum output frequency is 80hz. What I’m gonna do with this sir please help me. Thank you very much.

  • luffy says:

    Sir need help. i already done with the circuit but i can’t achieved 60 hz and 220volts. my output frequency is very high and my output voltage is 40V only. what i’m gonna do with this sir?

  • shreya ss says:

    can i use 12v 10Ah battery,,,?.is it makes any damage to the circuit,,?.
    replay me

  • shreya ss says:

    Hi frenz i want a PCB(glass epoxy) for the above ckt,anybody give it for cost pleez…replay me

  • vasudev says:

    hi which is the best one ,i mean is the inverter using mosfet(& cd4047)is bettter or this

    • Seetharaman says:

      Mosfet will be superior as its on resistance is quite small comparing to bipolar transistor counterpart. So the loss in the final stage will be quite less. Heating also will be less. Most important is MOSFETs cannot be destroyed due to thermal runway, as they are of PTC characteristic.

  • vasudev says:

    hi which is the best one ,i mean is the inverter using mosfet9& cd40470 is better or this one

  • Jothiprakash says:

    shall we use this for converting the 12v to 440v?

  • prashanth says:

    what rate of battery required this ckt

    • Seetharaman says:

      Hi Prashanth with 12 volt 100va inverter with an efficiency of say 80% you have to feed in as 125VA. That is 10amp current from 12volt battery. for say 5hrs running non stop you require a 12 volt 50AH battery.

  • prashanth says:

    I want a load regulator circuit diagram for the above ckt

  • dafe says:

    this inverter circuit does the batterty charge when there is power from the electric company or it only inverts (give out power)?

  • Geo George says:

    I’m an electronics student.. kindly help me with some tips so that i can convert my 600va computer ups into an inverter. i have an external battery ,to replace the 7 ah internal battery. what changes are to be made??

  • Alo says:

    Is there any video i can watch to enhance proper understanding of this inverter eg youtube.com etc …

  • The pin 12 of cd4047 is to be grounded for the circuit to work.

  • vinith says:

    can any one tel me the working of a 20 watt inverter

  • Vique says:

    This project sounds good..can someone please send me the full details?.i.e block diagram,calculations n the design.please.

  • nithin says:

    I want a circuit that works as a duel charger(600-800 watt)Inverter AC & Solar Parallel And If possible Need Separate Circuit of Solar Charging with battery full charging Controller with auto cut and if need after solar charging battery itself can get charge form AC.Basically Add on Circuit that be integrated with existing 600-800 watt Inverter used 12v 180Ah Inverter battery.Its Need if possible solution.reply on my mail.

  • vinith says:

    is the curent ratings necessary for the components to function……we r using a 2 amps 12volt supply…..

    • Seetharaman says:

      Hi Vinith The supply will give you 24VA with an efficiency of say 70% you will get around 16VA. For this circuit with the rated transformer in circuit you require a 12 volt 12Amp power supply.

  • Nani ramesh says:

    What is the output voltage of ic

  • nani ramesh says:

    respected sir,i appreciate your circuit,can you give full of it’s working operation………..plz

  • gokul says:

    please can you send me 200 watts inverter circuit diagram

  • Sarah Paul says:

    sir,is there anyway to get a sine wave output instead of square…or is there any additional circuit that could do the job…plz reply sir,i am doing a project on this…

  • malik says:

    sir i.m working on this circuit from two months but output voltage is 0.only two transistors of one side are heating. i,m using 12-0-12 transformer?

    • abdullah says:

      hi malik i am a student of electronic engineering . i want to mae an inverter circuit. i am working on this circuit from 15 days and same problem i faced my one yransistor is heated and output is 0.do you have any circuit.

  • Hassan says:

    Can anyone tell me which IC can be used as an equivalent for IC CD4047 used in the cicuit?

  • Hassan says:

    If someone has done it simulation on MATLAB or Multisim. Can you please post it here. I’ve problems doing that!

  • jumana says:

    is it ok to use transformer with 12 0 12 rating ?

  • naseri says:

    hi im naseri i need project boost 10 t0 20 volt 20 wat please post me the circuit of 20 wat

    tank you

  • DQHHN says:

    I’m seeking circuit diagram of Powercom UPS 1200-A. Pls send me if you can.

  • undergraduate says:

    respected sir ,what is the current rating of battery ?and we are using 10 A transformer in reverse order ,it means we ve to supply now 10 A to tranformer to get the required 100 W power ,is it right ?and can this ckt can supply 10 A through transistors ?plz peply quick i m making this project . or any one in this forum can guide me

    • rohin says:

      hi you can use battery up to 100ah. 100amp battery is ideal for this circuit.there is so many things to understand for this circuit.you can use ups battery 7amp but for a life of battery it should be charge and discharge with 10% of it ah rating.the rating of transformer is not mean that we give it 10amp current to get 100w.the current of transformer increase automatic according to load.you can ask any question on my maid id is rohin.sharma83@yahoo.com. happy to help you.

      • undergraduate says:

        can i use 12 v,5Ah battery for this circuit ?i think 100ah is too much ,will not this high current rating can destroy the ic ?second i know a formula for transformer, primary power (vp ip )=secondary power (vs is ) we are taking primary voltage vp =220 volt ,primary current should be ip =0.45 A (as 220vp x 0.45 A =100 WATT ) .secondary voltage vs =9 volt we are delivering then by formula is =vp x ip /vs
        =10 A that we should ve to supply to get ip =0.45 A (now plz tell me is this formula ,my concepts and calculations are right ?and how a load can increase transformer currrent ratting ?plz reply soon i m waiting

        • rohin says:

          you can use 12v 5ah battery but then use only 50w load for safety and long life of a battery.my dear it look like you are new in electronic so its become difficult for you.how can high current can harm the ic.it will brust only when you give high voltage.your formula seem headache and your calculation is very wrong.here is 220v side is secondary and 9 0 9 which mean total 18 v is primary and why you are calculating with 10amp and 9v . 10 amp is max transformer rating for safety.it never mean that we give it 10amp to get 220 v.i told you that current of transformer primary increase when you connect a load on it secondary.it does not mean that a load can increase the transformer current rating it will remain same all the time which is 10amp in this circuit.

          • undergraduate says:

            basically i m in 3rd term and new to electronics ,and got confused in mathematical calculation ….i got ur concepts ….i practically perform this circuit ….by my opinion its giving square wave …will this sort of wave not harmful for appliance although they are low power appliance …can this decrease the life of appliance ?if i want to convert it to 200 watt how much current rating transformer will then i ve to used ?can we convert this wave to modified sine or quasi square wave and thnx for ur all replies sir …

  • malik qasim says:

    can i use this circuit for battery charging also, if yes then how?

  • Jeyakumar says:

    haribalaji u number missing,i want to 100watts circuit

  • Adnan Ahmad says:

    my 100 watt invertor not running plz help me?

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  • vasanthan says:

    what is the ampere rating for the 12V battery?

  • haribalaji says:

    very good simple circuite and easy to available in the shape.
    thanking u….

  • c.m.vel says:

    how much the 100W circuit price?

  • Zaid says:

    sir can i use 12-0-12 2 amp transformer



  • DHANASEKAR says:

    thanks for ur provide

  • dhanasekar says:

    what value resistor can be used instead of pot resistor pls rply me immediately to my mail

    • Seetharaman says:

      Hi Dhanasekaran it has to be a pot to set the oscillator frequency to 50Hz, this cannot be avoided due to component tolerences.

  • judie says:

    is this circuit applicable for computers?

  • Praveen says:

    sir i am a learning person…in this circuit battery charger include.?

  • vijay raja says:

    sir when i connected this circuit and gave a 12v 7.5A supply,the zener diode D2 burnt…
    shall i knw the reason of this & the error in my circuit…???

    • Seetharaman says:

      Hi Vijay please see my comment dated 2nd May 2010, the modification has to be carried out for the inverter to function.

  • Seetharaman says:

    Dear Scott this circuit with the standard transformer can work upto 100Hz max. For higher frequencies you require special transformers and drive circuits, which will not fall under this project

  • Scott McKie says:

    Dear Sir,
    Can this circuit work at a multi-kHz rate in order to chafge up a high voltage capacitor bank attached to the secondary? The rate would be around 450kHz.
    Thanks in advance,

  • Rajib Banerjee says:

    I want a circuit that works as a duel charger(600-800 watt)Inverter AC & Solar Parallel And If possible Need Separate Circuit of Solar Charging with battery full charging Controller with auto cut and if need after solar charging battery itself can get charge form AC.Basically Add on Circuit that be integrated with existing 600-800 watt Inverter used 12v 180Ah Inverter battery.Its Need if possible solution.reply on my mail.

  • Unknown says:

    Hey thanks about the circuit.
    can i load a computer with a 5 ampere transformer????
    Because I’m going to build one.
    If it’s not possible, please let me know how to do it.
    I need it so much.please!!!!
    thanks a lot.

  • jud says:

    sir, would all the 6 transistors be mounted on a heatsink and what are the required dimensions? for how many minutes will this be running until the batts are dead? and if i connected in parallel 2 car batteries will it work twice as long with only one batt?
    thanks in advance really need your help

  • avinash says:

    Sir can u give me any high volt circuit

  • Sir,

    I am searching circuit for solar charge controller(PWM and MPPT).

    Please help me.

    With regards,

  • zama says:

    the circuit works well but i dont know the full operation.

  • zama says:

    hi, sir {i want to know the whole operation of this 100 watt inverter circuit.

  • Dinesh says:

    can i use 230v ac to 9v ac step down transformer or 230v ac to 12v ac step down transformer as t1

  • fredz says:

    I love circuits

  • seetharaman says:

    Hi Adnan 2N3442, 2N3773, 2N6254, MJ15003, MJ15022, can be used.

  • adnan khan says:

    hello sir I asked you aquestion about transistor 2n3055.plz tell me this alternative transistor who can be used in the inverter

  • ktjayaprakash says:

    I want to start 3 cfl inverter. Please give circuit 45 watt 12v 7.2ah battery
    Yours faithfully,

  • Amit says:

    hi, i want to build a 300w inverter, what changes do i need to make to the circuit?

  • indrajoti says:

    I want to make dc12v input & ac230v 200W chopper type inverter circuit diagram please support me

  • channa says:

    what is the necessity of using diode? please reply.. fast..

  • Nuhu Chiduo says:

    Sir,i need to design an inverter to be used for tv and charging telephones,please if you have a practical circuit diagram,please help me.Mail me please.

  • Dhanasekaran says:

    Hello sir,
    I want to make the DC(12V) to AC(230V) “pure sine wave inverter circuit”. Please if you have any circuit or ideas please mail me or post here. I want the circuit design for minimum 100W power output with 230V pure sine wave.
    Please reply me i am waiting for your reply!
    thanks all……

  • deepak says:

    Hello sir,
    I want to make the DC(12V) to AC(230V) “pure sine wave inverter circuit”. Please if you have any circuit or ideas please mail me or post here. I want the circuit design for minimum 100W power output with 230V pure sine wave.
    Please reply me i am waiting for your reply!

  • Seetharaman says:

    Kiran you can use with 14″ TV. most of the LCD monitors consumption are around 130 to 190 watts, hence may not be possible to use. check the TV power consumption and use if it 100watts or less.

  • kiran says:

    can i switch on a TV?

  • Seetharaman says:

    Hi John since we are using 10 & 11(f/2 complimentary output), 13 is not required. The above application is correct please (refer my comment dated 20th july and)follow. Around INR500(price depends mainly on the quality of the transformer)

  • john Bhat says:

    does pin no. 12 and 13 remains unused????? in CD4O47 pin no. 13 is oscillator.what happens if we use it in the circuit?????

  • john Bhat says:

    how much will it cost????? plz rply

  • seetharaman says:

    Hi Raju you have to use a 12volt battery with 50AH capacity. for 100watts for 5 hrs backup.

  • raju says:

    how much the cost for 5hr backup one

  • seetharaman says:

    Hi Sathish IC1 is the oscillator with complimentary output. which switches on driver transistors Q1 and Q2 alternately. Which in turn switches on the output parallel pairs Q3,Q4 & Q5,Q6 alternately. Due this action the primary winding of the transformer is switched on alternately with 12 volts. this waveform is stepped by the transformer and it gives you the stepped up 220volt square wave output.
    Hi Stevebit please go through my 20th july comment. kindly carryout the modification for the circuit to work.

  • sathish says:

    can u tell d stepwise procedure how it works???

  • stevebit says:

    hi any one from kent in here cos im working there next week and need a bit advice on best hotel the company i work for pays the bill
    steve bit

  • alfred beilin says:

    good day everyone all the best to yous for 2012
    alfred beilin

  • haidar says:

    hi sir,can u give me latest schematic diagram include modified circuit..i already try this circuit but not give correct output voltage..
    thanks for the help :)

  • seetharaman says:

    Hi Haidar it is rated for 10 to 12 amps (9-0-9 @ 100VA rating)continuous rating.

  • Hai.. I want to construct a simple 100watts inverter..
    I hve 12V bttry lead acid.. How much time it wl gve supply when battry is fully charged.

  • Hai .. I want to know ,in inverters, whether we hve to use only step up transfmr or normal step dwn trnsfmr in reverse.’ sir plz reply me.. I hve stopped my inverter projct for this doubt..
    Thank u..

  • StarD14 says:

    How much amps for transformer 9-0-9/230v should i used?

  • haidar says:

    what the amp of transformer 9-0-9/220v

  • seetharaman says:

    Please refer to my 22nd July comment on the above, you have to carry out the modifications indicated. you can replace BY127 with 1N5407.

  • StarD14 says:

    Hi sir, i already test your circuit, unfortunetly the zener diode 9.1v, 500mW damage.
    What can i do?

    I also have several other question to ask.
    1.How much amps for transformer 9-0-9/230v should we used?
    2.can i replace BY127 diode with 1N4007?
    3.how many volts and watts for this diode.

  • Seetharaman says:

    Hi Hyder the transformer winding will be switched on by Q3,4 and Q5,6. hence you have to use a center tapped transformer.

  • haidar says:

    hi sir..it is compulsory to use center tap transformer?can i use normal transformer?

  • ram says:

    hi, i want 100w inverter board. i am in trichy now. here the inverter boards are not available. pls send me the adress and any electronics stores in tamil nadu

  • eltee says:

    pls i urgently need a 300W or 500W inverter circuit diagram and reasons for using rated components its for my final year project….

  • wyclif says:

    pliz send me 500watts,600watts,7oowatts,800watts,900watts and 1000watts inverter circuit diagrams.send them to my email

  • seetharaman says:

    Hi Tapas you have to use 11-0-11 for required output. CD4047 output drive current is much higher than hcf4047. ref my july 20th comment on this. have you carried out the required modifications. you can try reputed make 2N3055 or BD249.

  • tapas says:

    is hcf4047 work insted of cd4047.
    the 2n3055 transistor are getting heated.
    if i use 15-0-15 of 3A.
    reply me soon

  • Shelly Jardin says:

    Thank you very much I will try that.

  • seetharaman says:

    Hi Shelly see my earlier comment.
    May 2, 2010 at 7:40 am
    Hi Imteaz A small change to be carried out in the circuit for proper operation. Shift +12 volt to fuse. include 470 ohms between fuse and supply of IC 4047 (between fuse and zener with 220uF capacitor). Add 4700uF 25volt capacitor in parallel with 0.1uF capacitor between centre tap of out put transformer and supply negative, nearer to 2N3055 emitter resistance(in other words in parallel with D1 BY127). You can connect 2 more 2N3055 also Q1 and Q2 can take care. IC can give a drive of 1mA which is sufficient to drive 4 to 5 2N3055 transistors through TIP122. Do not forget emitter resistance for 2N3055s. Increase fuse rating to 20Amps. Out put transistors wire dressing will be critical and important be careful.

  • Shelly Jardin says:

    I have been trying to build the inverters as a side project and I used both your 100W schematic and the 60W schematic and purchased everything as you have them. I put it all together but am getting nothing when I put the 12V to them. Do you have a troubleshoot guide that I can see. I have gone over each connection several times and it is as it shows on the schematic. Please reply soon. Thank you.

  • seetharaman says:

    Please read my comment dated 2nd May 2010. Carryout those modification. this is the best circuit for your UPS.

  • M waqas says:

    i want to make small ups… is that circuit absolutely right to implement..?????

  • pls Sir I need the details of the function of each component and all possible calculation done on the circuit, why the component are there and why that value. I really need it urgent for my project defence at school. I mean the 100 watt inverter. Thnx Sir, God bless you.

  • lalit says:

    kindly provide me the proper PCB layout of the diagram

  • usman says:

    Send me 500w circuit

  • usman says:

    i need to know that how much load a circuit can drive(100w inverter)?
    means how many fans and energy saver for how much time can be drive

  • Seetharaman says:

    Hi Musthafa 0.022 is 22nF (22KPF or 22000PF). Measure the voltage at Pin No 10 and 11 with respect to common negative. If oscillator is running the DC voltage should be half the supply voltage. If R1 is kept at minimum value the frequency will be less and you can see the voltage at Pin 10 & 11 raising and lowering (with an analog meter the needle will kick). If the voltage at Pin no 10 & 11 are either high or low continuously, indicates the oscillator is not running.

  • musthafa says:

    Thanks Frnd,How to check Ic4047 is working or not,And equvilant value of capacitor 0.022uf

  • Seetharaman says:

    Hi Musthafa you can use 1N5408 for BY127 R2 and R3 can 1/4 watt better use 1/2 watt as per ADM recommendation.
    CD4047 10 & 11 are complimentary out put to drive output pair. 7,8 and 9 are connected ground (-ve of the supply)
    4,5,6 and 15 should go to the +ve of the supply

  • musthafa says:

    My ID E-mail Address

  • musthafa says:

    HI! please tall me equvilant value of diode D1 BY127

  • musthafa says:

    Hi Seetharaman i Dn`t know to use the website & please tell the answers for my before comments.

  • Seetharaman says:

    Hi Mustafa circuit is ok. except for the mistake please refer to my comment dated 2nd may

  • musthafa says:

    what is the equ diode for D1 BY127

  • musthafa says:

    R2 and R3 value is 1/4 W it is the correct or not

  • musthafa says:

    i am sorry. the out put is 15v in first half & 16v second half.(i am check in d1 anode side o/p is 8,9 & check in d1 cathode side o/p is 15,16)tell what can i do.

  • musthafa says:

    8v in first half & 9v second half.& this circuit is wrong connection in ic4047.my gessing is the ic pins 4,14,5,6 are ground & 7,8,9,12 pins are connected in +ve supply i am right.and how much cost in transformer.what is the value of zener diode (i am check the circuit without connect zenar diode)i think it is the problem.any way thanks.

  • musthafa says:

    Hi! i h`ve some problem the output voltage,oneside 9v & other side 8v(with out transformer).wt i will do & The value of transformer Wil u please tell answer soon.

  • Sir , I like this , but I want to build 1000watt inverter circuit with solar panels.


  • Duane Morris says:

    Thanks for sharing your thought. I’m planning to make an inverter using this circuit diagram. I hope you will give me more guides and tips on making this kind of inverter.

  • Md imam uddin khan says:

    Hi, I want to make a 100 watt/12v inverter using high frequency trunsformer with common parts available in local market.please send me the document datails by e-mail.


  • akash gopi says:

    sir i can’t connect the output to the main because it may cause over load, can i use one diode in out put terminal and it connect to the main or you suggest me a solution

  • Seetharaman says:

    Hi Akash 1/4 watt will do.

  • akash gopi says:

    thank you sir and one more doubt what is the wattage of R2&R3

  • Seetharaman says:

    Hi Akash 100watts say efficiency is 80% 125VA input to final transformer. That is 12 volt at 10Amps approx. So for 1hr 10AH battery. for 3hrs 30AH battery. standard car batteries are 12 volt 40AH. you can use them. the cost of battery is around INR2500 and the inverter electronics with torroidal trasformer may cost you around INR700

  • akash gopi says:

    sir i need 3 hour back up which battery can use,what is the total cost for this inverter

  • Seetharaman says:

    Hi Thilina you want the circuit or assembled emergency lamp itself

  • Thilina says:

    Can someone please send me an emergency lamp. that can be run at least 2hrs , using 6V battery, and mobility

  • Seetharaman says:

    Hi Vivek Mount one group of transistors in one heat sink directly. insulate heat sinks from chassis. Wire the IC in a standard pc board and inter connect. Regarding power supply modification please refer to my comment dated 2nd May. without the modifications you will blow the zener diode.

  • vivek says:

    please tall me layout of 100w inverter. and how can i make it.

  • Seetharaman says:

    Hi Ruchir pl refer my earlier comment on may 2nd.even after modifying if it is not working, check the output at cd4047 pin 10 and 11. if there is no output the IC may be defective or the timing components are not properly getting connected.
    Hi Gopi refer my earlier comment dated aug 23rd. for 3 hours at the rate of 14 amp consumption you require a 42AH battery. 40 amps SMF car battery can be used will cost you around INR4300/- (Amron, Std, Exide etc)

  • philip says:

    pls how may i get a design of 5000watts mosfet or any other type of power inverter. but it most be up to 5000watts,wit the components well indicated.countin on u hopefully. Tanx

  • akash gopi says:

    sir i need 3 hours backup for the inverter, what is the AH of the battery?, what is the cost for it? Please give me reply…

  • ruchir says:

    hey my inverter is not even working….. checked all the components four times…. please suggest me a way out….

  • seetharaman says:

    Hi Anoop Q5 & Q6 are also 2N3055 like Q3 & Q4. Say inverter efficiency is 80% for 100 watts load you require 125VA input with 12 volt battery you require 14 Amps current. Hence with 7AH battery you will get approximately just less than 30minutes.
    Hi Imran You can change the frequency to your requirement with pot R1. Zener to regulate the supply to the IC oscillator so that its frequency output is stable. There is a mistake in the circuit refer to my earlier comments on 2nd May.

  • Imran says:

    Hi! Wil u please tell u know about the function of zener diode n can v replace the ic cause its in astable mood so v can use any in this mood……n y here 2 100hetz in this y not 120hetz… Please give me reply…

  • ANOOP says:

    Hi, Can you tell me the values Q5 and Q6 and calculate the working hours of 100w equipment with 12volt,7Ah battery? please

  • Seetharaman says:

    Hi Daniel battery DC to covert to AC there will be a loss of 25% and again convert AC to DC and charge battery another 25% loss. Hence this is not viable proposition. It is something like connecting motor to dynamo mechanically and connecting dynamo and motor electrically thinking that it is perpetual and run for ever if you take all the losses into consideration this is not viable. Say even if it is 100% efficient what are you going to achieve, you cannot tap power from the system due this loss the system will collapse.

  • DANIEL says:

    I am thinking of designing an inverter in which its output(AC),is fed back to charge the battery when it undergoes low voltage and vise versa,and this oscillation goes on continuously,ie,automatically.
    Can you provide me a full circuit diagram with parts list?
    Thank you in advance.

  • seetharaman says:

    Hi Imteaz A small change to be carried out in the circuit for proper operation. Shift +12 volt to fuse. include 470 ohms between fuse and supply of IC 4047 (between fuse and zener with 220uF capacitor). Add 4700uF 25volt capacitor in parallel with 0.1uF capacitor between centre tap of out put transformer and supply negative, nearer to 2N3055 emitter resistance(in other words in parallel with D1 BY127). You can connect 2 more 2N3055 also Q1 and Q2 can take care. IC can give a drive of 1mA which is sufficient to drive 4 to 5 2N3055 transistors through TIP122. Do not forget emitter resistance for 2N3055s. Increase fuse rating to 20Amps. Out put transistors wire dressing will be critical and important be careful.

  • Imteaz says:

    Can I increase wattage by adding another 2N3055 parallel to these two. If so is there any other changes required (for Q1, Q2, R2, R3)?

  • Imteaz says:

    Will it be very harmful if I use 120W load?

  • seetharaman says:

    Hi Sat the ampere hour capacity is given on the battery by the manuacturer. If you use 6 volt 7 ah two numbers in series, then 12 volt 7ah will be the capacity of the battery.

  • Sat says:

    Hai,how to check the battery ah,

    i have connect the two 6v battery whether, the 12v battery

  • Sayyed Aamir Bashir says:

    Thanks 4 publ such a ckt. Every electronic professionalist gets lots m

    Sent on a phone using T9space.com

  • Imteaz says:

    Can the watt of this inverter be increased? Can I use powerful transistor to increase wattage? What kind of wave output of this circuit (sine or square)?

  • Arman says:

    Can any one give me the pcb layout of 100watt inverter..Its an urgent…Plz

  • spider says:

    thanx a lot:-))

  • seetharaman says:

    Hi Pin 14 should be connected to plus 12 volt supply. 12 & 13 not to be used as we donot require those functions. If you have a multimeter you can check the out put voltage connect a 60Watt bulb and try whether the glow is not flickering. if you have a frequency meter check for the frequency at the out put. if you do not have any test gear connect a bulb if it is glowing alright, connect a 230V 50Hz table fan to the inverter output and slowly turn the frequency pot till the fan speed gets peaked(runs almost at the same speed like when it is connected to mains supply). in this crude method you can adjust the freq. approximately.

  • SPIDER says:

    what to do with the remaining pins 12,13,14 of the IC 4047?
    how to check the operation of each component when i connect a 12 v Dc supply?..
    how to know whether the POT R1 is adjusted at 50Hz?
    please reply:-(

  • seetharaman says:

    Hi Hamisu Ahmed kindly send your your fine designs to Circuits today. we will all be benifitted.
    thanks. awaiting your designs

  • hamisu ahmed says:

    design of electronic circuits is my field of study (bsc. physics)

  • shakti says:

    tel me about i/p o/p pin configuration of ic A316J use in inverter

  • judekingsley c says:

    this circuit is very much fantastic but pls. can you help me with a 1000winverter circuit diagram

  • peter says:

    sir can u send me pure 300 – 500watts sine wave circuit diagram that can use for my laptop and printer

  • kashif says:

    can some one send me the 1000 watt invertor circuit if greater its fine thx

  • kashif says:

    hey there thax for this circuit i been working with the solar cell for quite some time and this invertor circuit is just what i need could you please send me some more of these with proper ratings and i also need the controller circuit between the solar pannels and 12 volt car batteries as is very important for solar cells to generate energy

  • Seetharaman says:

    Hi Jeffreywong you can use sine wave oscillator circuit appeared in Circuits Today using ICL3038 with a buffer and a push pull power amplifier using diver transformer, MOS Fet transistors and a suitable torroidal step up transformer (T1 of above 100 watt inverter circuit) you can make a good sine wave inverter with reasonable efficiency. Happy designing.

  • Sakir says:

    Sir i want to know how to make 12 v battery charger and i want clear diagram about how to connect battery. Plz send to my mail.

  • lokesh says:

    Dear Sir,
    i am a regular visitor of ur web, FIRST of ALL am very THANK FULL for ur services.
    I have 2 things
    1.I need a good inverter which o/p will be above 500watts
    2.How can we calculate the duration of a battery to utilize after reacharging that {i mean if we are connecting a 6v battery to an led circuit how long it may work}

  • jeffreywong says:

    Hi sir, im doing a pure sine wave inverter, during the progress, i have face many problem until i cant move on to it. Can sir assist me to complete it? Or sir can send a pure sine wave inverter circuit to my mail box? emergency…

    Thanks a lot…

  • Zul_BjQ says:

    Is this half-wave or full-wave inverter?from what can i understand it is a full-wave..correct me if i’m wrong.

  • rajasekaran says:

    i need a 800VA inverter circuit for my project. can u anybody send the circuit soon to me…

  • obed says:

    i want a 1000w invertor

  • qudeerbasha says:

    hello sir ckt is good but i want the ckt to worker on solar power ies the i/p to this solar power

  • vighnesh says:

    would you please send me the circuit diagram for making a 600VA inverter. Also please send me the list of components used and the instructions to make it

  • n.srinivasarao says:

    pls can you send me a 500watts inverter circuit diagram with exact sinewave out.

  • ANANE says:

    Please I need more information to perform my project on the 100-watt power inverter.

  • radhi says:

    hi.. plz can u give me a circuit daigram of 600w inverter using MOSFET.. do mail it soon as possible… thank u……..

  • abdul says:

    what is the value of q5,q6 transistor?

  • pirate says:

    i had heard that there’s such thing as electromagnets that can cause a pc computer be paralyzed or destroy the hard disks. is it true? since its my first time to visit this site.


  • vevek says:

    I used the IC HCF4047 instead of IC1 Cd4047.Why so i did not get the output Sir? And I used MB1270B 12V , 8Ah(lead acid rechargeable battery). Can U please help me to get the proper output, Sir? And I want know the operation of IC & Transistors used here.

  • vevek says:

    I used the IC HCF4047 instead of IC1 Cd4047.Why so i did not get the output Sir? And I used MB1270B 12V , 8Ah(lead acid rechargeable battery). Can U please help me to get the proper output, Sir? And I want now the operation of IC & Transistors used here.

  • Techmaster says:

    what Will happen if I a transformer of 15-0-15

  • jeffreywong says:

    im looking for a most advance inverter, from 12Vdc to 240Vac inverter. If you have this kind of inverter, please share with me and send the full circuit diagram with it explanation.


  • twits4twats says:

    Please remember, 230V AC KILLS.
    As ADMIN has stated, this is not a very efficient circuit and allthough it will suffice for many an application, it has it’s limits.
    If you are buliding this circuit with the intention of using it to drive a mains battery charger for a portable unit (laptop or some such thing), it is highly likely that it won’t work.
    The output of this inverter is known as a dirty sinewave and most chargers these days will not accept it as an input.
    Having said that, there are still may applications that this could still work for.
    The only way to learn is to do it.

  • abankwa says:

    pls can you send me a 500watts inverter circuit diagram

  • Recently, i was making an inverter with transistors. it was drawing 0.06A but when i tried to increase its consumption for a proper output it didn’t work. is it bcause of the transistors that m using?

    • admin says:

      The problem can be anything.I have few questions
      Did you got a proper output waveform in the oscilloscope?
      Have you checked the output of the oscillator section?
      Which transistor you used?
      Had the transistors burned out?
      Was your battery powerful enough?
      If you send me the circuit diagram I can help you more.
      Just mail it to info@circuitstoday.com

  • joshua says:

    good posts, Azzoarq is right.

  • azzoarq says:

    @ idris
    to produce 1000W from 12V DC you must have 83-85 Ampere….!!

  • delaw says:

    hi, this is good for our consumption.


  • idris ado says:

    this inverter is good, but i like 1000w with principle opretion

  • onyebu says:

    please can you send me a detailed explanation and diagram of how i can build a 600watts inverter and a 12v battery charger

  • sil says:

    thank you sir for the website you have provided. i could understand what actually an inverter is but the problem with me is what is the purpose of IC1, the diode D2, TIP122, 2N3055. and how are these components corporate eachother and all.
    could you please mail me the detail sir? i would be very much grateful.

  • sil says:

    i’m here havig difficult time to understand the working of this diagram. can anyone, explain me the working mechanism of this diagram, please?

  • sil says:

    i’m interested in the circuit. so, could you please advice me how should i design an inverter circuit for 1000W.

  • john says:

    need help for my 500w inverter project.

  • olabode says:

    cool386,please can you teach me to build an inverter starting with this circuit diagram of 100watt,and how i can increase it to 5000watts in a well explained way naming/labelling the circuit diagram in an Email

  • Chris says:

    What can you do to increase the frequency? Say to 400 Hz?

    • admin says:

      the frequency can be adjusted by varying R1 or C1. For 400Hz you need to decrease R1 to around 25K and keep the value of C1 0.022uF itself.

  • Mark says:

    can someone provide us a charger of lead acid battery but our input is a 24V DC motor.. consider that our input varies due to variations of required 1200rpm of the motor.. plz help us.. we need this diagram as soon as possible.. plz email us at manacled_man@yahoo.com

  • Cargoo says:

    Could you send me a 200 wats invertor circucit diagram, please. If it´s possible with calculation of individualy parts… It´s very importatnt for me. Thanks a lot ;)

  • azzoarq says:

    cool386 is rigth… You must using 9-0-9 to get high voltage

  • Larry says:

    Thanks for this circuit diagram. Please, can you tell me where the -12Vdc will be connected.

  • sunny says:

    pls can you send me a 500 watts inverter circuit diagram

  • cool386 says:

    These inverter circuits will give low output voltage unless a transformer with 9-0-9V primary is used. I’ve been building inverters for over 25yrs and know what I’m talking about.

    • admin says:

      oops that was a type error when I created the circuit diagram.The transformer has to be 9-0-9. Otherways you wont get the required output voltage.
      Around 2 to 3 volts will be dropped by the circuit and what the transformer primary gets is battery voltage minus this drop (ie around 9V).Thats why a 9-0-9 to 230 V transformer is needed.
      I have corrected the diagram.

      thanks cool386 for pointing the error

  • ammar says:

    I like this circuit but I need 500W UPS for my project so please post me the circuit of 500W UPS