My first intention was to design a DC Voltage boost converter to convert 3vdc to 5vdc so that I could power my iPod or any other device requiring 5 volts to charge.  I read about oscillation circuits and boost converter circuits and combined the two.  My results were staggering when I was able to convert 4.5 volts to over 100 volts by accident.  I decided to post an instructable for this instead, for now. If you have any tips to increase the efficiency or output current please comment below, I appreciate any suggestions.

Step 1: Obtain Parts

Picture of Obtain Parts
All components can be found at RadioShack.
     3 X 1.5 volt Battery Holder
     L1     RF Choke                   100 micro Henries
     R1     Resistor                      10 Ohms
     R2     Resistor                      51K Ohms
     Q1     PNP Transistor          2N3906
     Q2     NPN Transistor          2N3904
     Q3     Power MOSFET         IRF510
     C1     Capacitor                    .01 micro Farads
     C2     Capacitor                    .047micro Farads
     D1     Diode                           1N4148

1-40 of 96Next »

I found a 12V to 15V step up converter on Ebay. It has a +/- input and a +/- output wires. If I were going to use this on a car, how would you wire it up having four wires? Could you connect both the negatives to the car's chassis and feed 12V to the converter and 15V to the accessory then ground the accessory to the chassis? Or does it have to be grounded back through the converter?

This would be used to speed up a wiper motor.

There's a very big chance both negative IN and negative OUT are already connected on the PCB. If so, you can indeed connect GND to the chassis without using extra wires. Be sure you're not driving some special ancient car, which has +12v connected to the chassis though.

MattK131 month ago

lushprojects DOT com/circuitjs/circuitjs.html


pastebin DOT com/kf67QtMA

Tweek it and lets make this work! I tried and get 0 volts out.

jenriquez21 month ago

where can I get 100uH RF Choke??

sinas19 months ago

How can i boost 9VDC-350ma to 9VDC-2ampre

carroty sinas11 month ago

Next Level impossible bro. use less resistance in your circuit and you will get more amps out of your battery or whatever you need to do.

valveman sinas14 months ago

You can't get more power out than you put in.

Jimmacle sinas19 months ago

You're trying to change 3.15 watts (V*A) of power into 18 watts of power which is impossible. You'll need a power source that can supply at least 18 watts of power.

Hi, can you help us convert an input millivolts to a higher voltage (around 9v)? Please, it would be a big help. Thank you very much!

This same circuit will probably not work because (just a guess) the transistor will probably need 500 millivolts to 1 volts to turn on. (idk this is what the base-emitter voltage is on some general purpose transistors) Depending on the use, you may want to use an opamp to achieve this. Could we have some more information to help you?

Nice work! Also try using electrolytic capacitor for C2 and a schottky-barrier diode like 1N5822 or 19 for better results. I once accediently made a similar circuit(joule thief) which flashes a 12V10W power LED from a single 1.5v cell.

skumar2291 year ago

hey, how can i achieve very high dc voltage like in kv

LGT300 skumar2297 months ago

if i am not wrong, you could use a transformer for that purpose :)

mabo samra LGT3004 months ago

transformer with dc i dont think so

It is very possible. The inductor in this circuit is creating a high voltage from a low voltage because it is being fed pulsating DC from the MOSFET that is fed from the two transistor oscillator circuit.

Replace the simple induction coil with a transformer that has a very high turn-count secondary, and you'll get much higher voltages. Use an ignition coil, and you'll have exactly what creates a spark in your car. In my 1951 Chevy, an ignition coil, otherwise known as an autotransformer, since the primary and secondary are connected together at one end, creates a very high voltage spark with from 5 to 7.4 volts, depending on whether the car is being started, or the generator is running. A while back I fitted the car with a 'Blaster' brand coil, which only requires about 3 volts to create a good spark, and so I wired it with a relay so that it receives a direct feed from the battery when the starter motor is activated, and then receives reduced voltage through a resistor once the engine is running.

You could very easily achieve thousands of volts with the 4.5 volts specified above and an ignition coil.

maps20156 months ago
aalejo7 months ago
I have some question it is the thing. Can my power amp rates 16 volt can power it by your design??? Pls answer me
Can I use this circuit to obtain 8v700ma from 3.6v2600ma bettery. How can I do this
sinas19 months ago

How can i boost 9VDC-0.35ma to 9VDC-2ampre

Beefnado10 months ago

It's watts that kill you, or more precisely, Joules(energy), which is current*voltage*time. As long as the voltage is high enough to overcome your resistance, you're toast.

Hi! everyone i have a problem cause i use BC249 for NPN and BC259 for PNP and a mosfet IRF630 and a source of 5vdc but why the output is just 4.87vdc. i do know where i got wrong. somebody can help me please..

hi. thank you for your info. i change R2 by variable resistor bot out put voltage did not change . i need 500v dc for out pot may i have this voltage in this circuit.?


hi. thank you for your info. i change R2 by variable resistor bot out put voltage did not change . i need 500v dc for out pot may i have this voltage in this circuit.?


hi . it is great. thank you

vipindv71 year ago

what is the use of transistor,diode,mosfet and capacitor in this setup...

vipindv71 year ago

i need the whole working of this project so that i able to make my report .can anyone help me plzzz..

Madoxa1 year ago

Its a very nice circuit thank you , i have applied the schematic and built the circuit but unfortunately it won't work i do not know where the problem is following some notes regarding my circuit :

V source : 3.7v battery


PNP transistor : BC327 NPN transistor:2n2222 the rest is the same as your recommendation

Simulation results Vout = 6.7 whrer my result Vout=2.3

any Tips or suggestions



I think it's the pnp and npn transistors

PNP and NPN are different and not compatible unless you invert the current which i believe is prettey complicated to do, try to find a PNP transistor, you can search for equivalents on: http://alltransistors.com/ if you dont have any, scrap a power supply or a radio you will normaly be able to find some on there.

hope it helps :)

To answer some questions here, even if I am a bit late:

ashot211: The reason MOSFETs heat up is mainly because the gate-source voltage (required to turn it on) is usually too low. Meaning, you likely have the wrong MOSFET. Did you specifically use the IRF510?

liamdeg: Ohm's Law says yes. However, batteries have a rating for how many milliamp-hours (mAh) they can put out - so, by using a higher current, you use up the battery faster. This is a proportional ratio.

antionlog: I use a 6V lead-acid battery, and the voltage is about 150V coming out. So, by that ratio, a 9V in would lead to about 200V out (196.51V, to be more exact). Likely, it would not actually produce such a voltage, because this is on the way-high end of most MOSFETs' capabilities.

amruth: See Ohm's Law.

Anyway, I put the diode in backwards and used the wrong MOSFET on my first try, so I plan to correct that today. The first MOSFET heated up to the point that the metal began to self-temper (turned an iridiscent sheen of colors due to oxidation by heat and air), and the voltage started at 150 consistently but dropped just as consistently. Hopefully, the IRF510 and the reconfiguring of the diode will fix things.

ashot2111 year ago
I just finished the circuit,it works but after about 2 minutes, the voltage starts slowly droping down to 4.5 v and mosfet getting hot .can you troubleshoot PLS
liamdeg1 year ago
Awesome circuit!!

Im curious about boost converters and the current they produce. Say its outputting 100v and you connect it to a 5 ohm resistor will you get a 20 amp current? or dose the boost converter affect/limit the current? thanks
liamdeg1 year ago
Awesome circuit!!

Im curious about boost converters and the current they produce. Say its outputting 100v and you connect it to a 5 ohm resistor will you get a 20 amp current? or dose the boost converter affect/limit the current? thanks
antioniog1 year ago
What would happen if i were to hook up a 9v battery to this instead of 3 1.5v batteries.
Boost converter
soufiemaak1 year ago
hey, thats a nice one,
i wanna make step up converter using 555 timer get 12v from 5v
can you send me circuit
thank you
juanjomf2 years ago
hello as I can make 12 volt dc converter to 12 volts ac ?
I am looking at taking 5v up to about 12v what resistor should I replace with a pot to find out what value of a resistor I need?
amruth3 years ago
how many amps come out from the output. Plz tell me waiting for a reply. Thx.
Umniscient3 years ago
Hi there, nice guide.
Suppose I removed the output diode. Would the modified circuit produce AC?
No, it will give the same voltage from the batteries
1-40 of 96Next »