We are quite familiar about inverters which convert a DC potential to higher AC potentials at mains levels.
However these units involve complex and expensive configurations for acquiring the required outputs.
A much simpler approach of achieving the above results is by employing a oscillator mosfet boost converter circuit.
If the waveforms are not critical for your applications this method can be a lot simpler and cheaper to implement.
Referring to the circuit diagram below, we see that the entire idea is based upon the versatile, evergreen IC 555.
Here it's configured in its standard astable multivibrator mode for generating the required pulses at a frequency determined by the resistors 4k7, 1k and the capacitor 680pF.
The duty cycle may be appropriately adjusted by experimenting the 1K resistor.
The output is received at pin#3 of the IC, which is fed to the gate of an N-channel mosfet.
When power is switched ON, the positive pulses emanating from pin#3 switch ON the mosfet into full conduction.
During the above periods the 12V high current potential is pulled to ground via the coil by the mosfet.
As we all know inductors always try to oppose instant changes in current polarity through it, therefore during the negative pulses when the mosfet remains switched OFF, forces the coil to dump the stored potential in it in the form of high voltage EMF pulse into the output. This voltage may be equal to 220V and gives rise to the required potential at the shown outlet of the circuit.
The above straightforward operation is repeated continuously at the given frequency providing a sustained 220VAC at the output.
The BC547 and its base network is introduced for limiting the output voltage to the required degree. For example if the required output is 220V, the 47K preset may be adjusted such that the220V mark never exceeds, irrespective of the coil back emf rate or the input voltage fluctuations.
The mosfet can be any 30V, 50 amp type, for example a NTD4302 may be used.
The coil wire should be thick enough to hold up to 30 or more amps.
If I convert a 12 or 15 or 50v to 230v can I connect this to home appliances if it is possible means please explain it in detail and if not means give the solution to implement the home appliances to it.
you can connect appliances which are SMPS based for exmple TV sets, LED lamps, amplifiers but not that require AC sinewave inputs like refrigerators, mixers, fans etc.
I can fool around with the RC timing parts of the ic to get the frequency but can you assist me with the coil, how man turns do you think I would need to get such high voltage.
you can try 100 turns initially, for more info you can refer to the following article
http://www.homemade-circuits.com/2015/10/calculating-inductor-value-in-smps.html
Can I adjust this to get about 40 to 60khz at about 400v ac?
If so do you have any idea how much turns I would need on the inductor.
yes that's possible by appropriately setting the coil dimension and the RC timing parts of the Ic
Sir, please, give me a..idea about dc to dc converter from 12volt to 36volt for my 30watt 36volt led chip.because,i have to drive this led light from 12volt battery…
Swapan, you can try the concept which is explained in the above article.
I need a circuit of 500 watt 12 volt DC to 15 volt DC converter
You make a mistake; put a high speed diode after switching.
If you work with SMPS, high speed diode always needed!
thanks, I have corrected it now!
Thank you Manjumdar for sharing your ideas regarding this circuit built. It has been really helpful.
you are welcome Miracle.
I am trying to tell you that if 150 watt voltage booster inverter is connected to 150 watt battery,without any load or minimum wattage of load on inverter.Then,battery backup depends on inverter rating or load rating????
it will obviously depend on the load, without a load the inverter will consume negligible amount of current.
Sir, if I connect 15 watt cfl bulb to 150 watt inverter with 200 watt battery.Then, how much hours it will keep bright.
Sudip, please calculate it here:
http://www.homemade-circuits.com/p/battery-calculator.html
sir how to get 24v in the circuit? and what is the frequency???
andrie, you will need to reduce the inductance of the inductor by some trial and error to get 24V at the output….for 24V you can remove the BJT and the zener diode stages which are shown at the output section of the circuit.
hello sir, please i want to make a transformerless inverter (no ferrite core transformer) with 12vdc input and 220vac as output, the wattage should be between 200watts and 500watts. is it possible?
sorry that's impossible….
Sir which ic I used for Dc 12v to 220v Ac up to 20amp current
I didn't understand what you are saying?
Sir you have mentioned that we can use TIP122 instead of NTD4302, then what should be the pin configuration of TIP122? I mean how should I connect the transistor into the circuit?
Dipto, yes it's possible, join its base to pin3 of the IC via a 10K resistor, emitter to ground and collector to coil
Thank you sir for your reply I will be using TIP122 instead of NTD4302 since I couldn't find them in the shop.
Sir
I want to make a power inverter for 48v dc to 220v ac. Plz guide me…
Krishna, you can try the following:
https://www.homemade-circuits.com/2014/11/48-v-inverter-circuit.html
Hi Swagatam !
May I ask if this circuit can be used to power a laptop charger ?
Thanks
Hi Roney, yes you can used it for charging a laptop from your car battery, the inductor will need to be dimensioned and tweaked appropriately until the required 19v is achieved…
You can get high voltage at high frequency (not 50Hz) but the current would be around 100mA. How much is your load?
ok I tried building this circuit on electronic work bench but only got 8v out,
keep the BC547 disconnected initially and then check…
Which coil would i use to get 110v at 50hz
you'll have to find it by experimenting with different number of turns.
hi iam doing a project in which i need to convert 6v DC to 230v AC . after converting can i use any electrical appliances from the output of 230v AC
search for any IC 4047 inverter circuit and you can use it for your application
hi swagatam majumdar,
is possible with this circuit to fed an solenoid water valve (7w) as valve of washing machine or an little motor (4w) as flat of wave oven?
maybe is better to think an inverter circuit more complex as that you have posted in other pages?
thank you so much
regards
andrea
Hi Andrea, for a DC application, the above circuit could be used, but for AC devices an inverter would be more preferable.
220v ac 2amp load
you will need a 400 watt inveter for that, the above circuit will not work
plz reply i m waiting
hello nitin,
please tell me all the technical details of your project, only then i would be able to suggest regarding the above circuit integration.
hello sir nice work…i m planing electrick go kart powerd by sewing machine motor can i use this circuit??
i have 30ah battery ..sorry for bad english…reply fast..thank u sir….u r genius,
Hi Swagatam
I am working to use this circuit (excluding the transistor network) as a simple laptop charger from car battery.
1) One option needs a mosfet with following properties:
25V, 5A and RDS(on) 3.5 Ohms
I am not sure if such mosfet is available because such RDS(on) value is for small current mosfets.
2) The second option is to reduce the input voltage to 6V but, that needs high current regulator.
Which of these two options is more practical?
Hi Abu-Hafss,
The first option looks fine, you can use a higher rated mosfet such as IRF540 etc. it would also work as good and fulfill the results.
But that is 44mOhms whereas I need 3.5Ohms!
it's 44 milliohms which is a lot better than 3.5ohms, meaning the ON resistance of the drain to source will be just 44 milliohms.
Hi Swagatam
Can this circuit be used to power a 30-40W soldering iron?
If yes, would 12V-5A input be enough?
Hi Abu-Hafss,
yes it can be used, 12v/5amp would be just enough for that.
Hi Swagatam
I am considering to use this transformerless circuit to provide high voltage in CDI. Any comments/modifications?
Hi Abu-Hafss,
Yes, it's worth trying.
Hi Swagatam
As per my usual practice, I have simulated this circuit and got following findings;
The frequency is 510Hz. If it is decreased to 50-100Hz, the output becomes more than 1kV.
The inductor is 250µH. The capacitor is 10µF.
Following is the wave pattern:
https://dl.dropboxusercontent.com/u/20969135/230V%20output.gif
There is one issue i.e. how do we convert it to 230VDC? The CDI capacitor needs HV DC for charging which is provided thru a diode (half wave rectification) but, this output cannot be rectified, neither thru half wave rectification nor full wave.
If the capacitor value is increased, the output decreases.
Hi Abu-Hafss,
You can experiment with the number of turns of the inductor for getting different voltage levels at the output, because that's the only component that is directly related with voltage boosting.
Hi Swagatam
The out put is sort triangular waves of AC 230V (fluctuating between 0-230V not between 230 and -230 at 510Hz. How do we convert it to DC??? Single rectifier or bridge rectifier is not working, the output remains the same.
Maybe, the simulator is experiencing some difficulties in performing the rectification. Based on your experience, if you simulate in your mind, do you think the rectifier/capacitor should work to give a smooth DC output?
Hi Abu-Hafss,
Just connect a couple of 10uF250V(in parallel) across the output, no diodes are needed.
sir can i use the polyester fluorescent ballast for inductor…
It will depend on the output voltage requirement, if the inductor is able to produce it then it would be fine.
Thank you sir for your reply, I'll try it.
Rashid
Hello Sir,
How can i modify this circuit to run a 150 or 100W fan.
Thank you in advance.
Rashid
Hello Rashid,
you will have to modify the coil by experimenting a little with the no of turns and wire gauge until it satisfies the conditions.
okay sure i will try that and see what is the result, Thanks again sir.
Thank you sir, I had tried joule before but the problem is the current supply is not high enough.I need at least 100mA. Can I know how to increase the current or is there any way to do it?
Use parallel wire winding, meaning use two or three wires together and then wind them as per the data, this will increase the current of the transformer,also you will have to use more number of cells in parallel for supplying the required amount of current.
Hi Sir, sorry to ask this question here as I could not find a dc to dc step up circuit in your forum. I am thinking is it possible to modify this circuit to step up 2vdc to 12vdc? Thank you.
Hi Unknown,
the above circuit will require a minimum of 4V to operate correctly, I think you should try the following circuit, might just work:
https://www.homemade-circuits.com/2012/10/1-watt-led-driver-using-joule-thief.html
Dear sir ,
I have a battery 12v 32ah sf sonic jet , how can i charge by home made circuit ,I would like to use it as 200 Watt CFL inverter, kindly help me to making a 3 amp constant current battery charger,
thanking you,
Jayanta Roy
Dear Jayanta,
You can try the second circuit shown in this link, but I am not sure about the transformer details you may have experiment with its size and wire gauge:
https://www.homemade-circuits.com/2013/09/half-bridge-mosfet-driver-ic-irs21531d.html
..actually I could not understand your need, what do you want to make, an inverter or charger??
Sir,your response pls to my above query,IRF3205 print facing us, 1st pint Gate, 2nd pin Drain, 3rd pin Source.
Pranav BM
Please refer to this post, it has all the details:
https://www.homemade-circuits.com/2013/05/55v-110a-n-channel-mosfet-irf3205.html
Thanks for the input sir, few query
1. how to use the DMM to test the frequency, what should be the frequency for this circuit.
2.can you help in understanding an inducted and its config in a circuit.
Pranav MB
Your DMM should have a frequency measuring option, normally indicated with "kHz" symbol, otherwise it won't help.
In response to the 555 frequency triggering, when the mosfet is in the ON state, the inductor stores the specified amount of electrical energy in it and during the mosfet OFF state reverts it to the output. This back emf from the coil constitutes the 220V at the ouput…
thanks sir,
DMM has the square wave symbol in it.
I checked all the configuration, however the IRF is getting hot. I shall try one more time reassembling them and let you know the status.
Pranav BM
you can use the square wave symbol range for checking the frequency operation of the circuit…..
if it's not working with a mosfet you can try a transistor instead, try a TIP122.
SM sir, I tried this circuit, the IRF3205 is getting very hot and the wires used to link pins in the bread board gets burned , Pin config of IRF3205, pin 1 connected to pin 3 of IC via 1k resistor, pin 2 connected to inductor out and pin 3 to ground.
It will be difficult for me to identify exactly how you fixed the mosfet, I hope you've put it correctly.
What kind of inductor did you use and is your IC generating the required high frequency?? these two factors determine the correct operating conditions for the circuit.
Sir, i do not have scope to find out the frequency, can i use the DMM? if so how?, ferret core inductor 41uH 00440A
Pranav BM
Yes you can use a DMM which has a frequency feature in it.
what appliances can i run through this circuit?
can i use this circuit for lighting 40W TUBE LIGHT WITH ELECTRONIC BALLAST?
does the output voltage remain same even after connecting some loads?
for 40uH how many number of turns of coil should be?
can i use 100uF/250v in place of 10Uf/250v capacitor?
thank you.
Good day sir.
yes it can be used.
output voltage will remain constant if the coil is calculated as per the load.
i do not have the coil data, you will have to experiment with it.
100u/250V will be OK.
what is 103 cap
0.01uF capacitor
This is a jok
May i try it at home
if yar
what are tha main pricaution
output of 555 is AC or DC?
it's pulsed DC
Hello,
I want to get 40V-50V output and around 100mamp current out of 3.7 V battery. Can this circuit do this with some modification? if yes please a Hint would be great help.
Thanx
yes it is possible by suitably adjusting the inductor turns, more number of turns will produce more voltage
Hello Mister,
Lately i have been working on a project that requires 400v dc supply. this 400v dc is to be pursed on an inductor to create a strong magnetic field every 0.02 sec. Now, when i try to use a thyristor, it requires a forced commutation circuit which i haven't made. when i use irf840- which is capable of carrying such load, it burns out.
could the problem of my mosfets burning be as a result of my mosfet driving circuit?
I can really appreciate if you gave me a possible circuit that can solve my above problem. be it with a thyristor or using a mosfet.
God bless you.
Thanks!
you can try this circuit:
https://www.homemade-circuits.com/2012/05/making-adjustable-electromagnet-circuit.html
replace the transistor with an appropriately rated mosfet.
connect the inductor upper end to 400VDC while the circuit positives to a well regulated 12V supply.
I always like your work Majumdar. I am an ICEN engineer and i always find your work interesting. keep up!
Good day sir,please how can we get 50hz from this circuit.thats why iam asking if we can get 50hz from the 555ic so that after the output is rectified we can oscillate it back to 50hz.thank u sir and sorry for my question.
Good day Abubakar, try different values for the 680pf until you get the required 50Hz…you may take the help of an online 555 calculator.
can i use p80nf55 mosfet
Sir thank u for your reply.please is it possible to get two frequency output each with different duty cycle at each output with one ic, like 555 or 4049.please help me on how to do it.thank u sir.
what do you want to make? without knowing the exact application it will be difficult for me to design the circuit.
Sir please is it possible to connect a ferrite transforme between the inductor.if not please how can we do that so we eliminate the regulator part of the circui and use ferrite transformer
you may connect the primary of the ferrite transformer in place of the shown inductor, the output then may be acquired from the secondary winding of the transformer.
but anyway the regulator part would be required for getting a stabilized output.
Sir,
Somewhere on the net I came across the information about the coil to be handmade and that would be perfect for this project.
Toroid Core (T106-2) with 0.8mm wire, 55 Turns for 40uH.
Could you describ which type of coil you had used?
What do you suggest???
Regards,
PP, yes hand wound torroidal coils would work nicely here…however I have not yet checked the circuit practically….i would hopefully do it soon.
hi sir iam going to do the project
sir have u tested the circuit?
Hi sir
We had a innovative since fare project
So I thaught of doing the circuit
Sir have u tested it?
And what is the coil rated
Please help me sir
yes i have tested it, it works, the coil will need to be experimented for getting the required output.
Sir,
How can I apply this circuit convert 12V DC to 50 V AC , at about 20 milliamp at 1hz per 10 to 20 minutes for an electrolysis project. (so I don't have to swap polarity every 10 min. on a DC battery.)
use a 10uH inductor, you will get the required output…..
Isn't the frequency determined by the resistors 4k7, 1k and the capacitor 680pF. Do we not need to change this values??
frequency has no connection with the output voltage.
can i use to supply my wooofer.
sir where is the coming – terminal from 12v dc
It is really very interesting Project
Sir,
I made a circuit which you shown in figure,in using of bc547 and lm338p….
but in this circuit output ok is 12.70 v ,but current is 0.01a
So what i do….
I want minimum current 10 to15amp…so which circuit i do…
refer to the datasheet of LM196 IC.
First Thanks for this nice model.
Sir what will be the overall cost for building this circuit.
Around Rs.150/-
Sir can you please explain me why we are not using any transformer in this circuit… because on net i have found that all circuits are have transformers.
The above design is a simple boost converter without negative half cycles, it will provide a pulsating DC only…a transformer type will provide full wave AC and will be isolated from the input.
WHICH MOSFET SHOULD BE USED?HOW MANY TURNS ARE REQUIRED FOR THE COIL?CAN THIS CIRCUIT BE USED TO LIGHT CFLs?
any 10 amp, 50V mosfet will do, coil turns will need to be experimented practically, yes can be used for cfls.
Hi Swagatam,
Is IRF3205 a good for this circuit.
wish you good day
Good day Basem,
At 55V/110Amps, it's a hugely robust mosfet, no doubt it would be good for most high power applications…. same for this circuit.
can i use IRFZ44N mosfet
Hello Sir,
I guess the Coil should be wound on Ferrit Toroidal Core..please correct me if I am wrong.
yes using toroidal core would be more efficient
Hi sir r u ter
Hello Swagatam,
I have 6 Pl lamps of 15 watt each, and 2 of 26 watt each the total is 142 watt
I use an ups fed by 12 v 110 Ah battery can the above circuit replaces my ups.
Best regards
Hi Basem,
if you design the inductor optimally, and get 1 amp from it @ 220V then it would do the job.
Good day
Thank u what AWG shall I use to make the inductor
Good day,
it's not critical, approximate a thickness which would comfortably handle the specified current, you can go for plus sized wire….added thickness will not do any harm.
Sir, how many hours can i watch on my 86watts of television if i use and follow your components device? if ever i want to increase the hours what componets can i change?
this circuit can be used for battery charger, and lighting applications only.
hello sir
can i use this circuit for charging of a dc input fan?
wat is the case when the input given 12v battery is discharged?
can i giv a input to this circuit by 12v rechargeble battery?
which mosfet i hav to use to this circuit (say the mosfet number)?
hello and thenx for your job in this blog.. i have a question what is the herz in this circuit and how with no transformer give 220AC ?
will try to update it soon…
sorry… frequency would be in kHz….the coil does the step up function…..
Can this circuit be slightly modified to design DC to DC by placing a diode to acquire 36V or even 48V to feed a pure sine wave inverter?
the coil is the main component which decides the output voltage, it can be appropriately dimensioned for acquiring any voltage level at the outpt.
how to make ac powered 3 watt led circuit
use cell phone charger to power it….
dear sir, the output is pure sine wave ? can i connect 2 fans (230 volts A.C) ?how can i make the coil? iam going to do this circuit. please help me.
No you cannot connect any applliance except lights
how can i make the coil?
can we give input inform of normal battery
yes we can do it….
pls help with high side 50hz circuit.
will try to update it soon…
what about protections in the circuit?
What are the resistor wattages (1/4 watt to be used)?
only the 10k zener resistor needs to be rated at higher wattage may be a 1 watt would do. rest all can be 1/4 w
nice one .. :))
how much watt/load can i put on output ? ..
up to 200 watts if the coil is appropriately dimensioned….
hello again,
i need to make a just opposite project converting 220v AC to 12v/24v DC help me please or please give me link of the same 🙂
It would be dangerous to use the above type of configuration for your requirement, you may try the following design:
https://www.homemade-circuits.com/2013/06/0-300v-variable-voltage-current.html
Obaid just take out 220V AC, add a step down transformer that makes it 24V and then add a bridge rectifier and two filter capacitors electrolytic 10uF 25V and a 7812 IC, u'll get 12V
In the schematic, the output 220 volts is connected across the drain – source terminals of the 30 v mosfet ??
yes it should be also rated at above 300V…you can replace it with a IRF840