DC Boost Converter

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

All components can be found at RadioShack.
     
     PCB
     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

Comments

[amruth]

how many amps come out from the output. Plz tell me waiting for a reply. Thx.

[Umniscient]

Hi there, nice guide.
Suppose I removed the output diode. Would the modified circuit produce AC?

[Kurt Gerhard]

No, it will give the same voltage from the batteries

[Zettu]

i put this schematic together with every component the same the power source is two AA's at 3v 2600mAh roughly the output voltage is 6.48v by putting potentiometer for the 51kohm resistor and turning it down slightly i was able to get 7v however the current output is really low and i'm not sure it would be effective for charging anything on usb even with a voltage regulator on the output to ensure 5volts, i was thinking of maybe experimenting with the a zener diode near the output somewhere rated at 5volts or maybe 12v and regulator 7805 on it, but i wondering how you got 100v cause i have another experiment that involves high voltage and low current for illuminating a gas tube or even a small fluorescent off of 2 AA's ,,,, let me know what you think about these ideas maybe we can collaborate on some ideas,, :)

[N3v3rm0r3]

4.5VDC input, at what amperage? I don't want to use batteries...

[gerbil_man]

Would this still be able to charge an ipod touch 3G?

[llamma1010]

The iPod's have a very weird charging system watch this video
http://www.ladyada.net/make/mintyboost/icharge.html

[Inducktion]

What kind of wave does it output? Square wave right?

[VicentiuB]

how many amp output from this circuit ?

[jules15]

Will this work for 350vdc to say 1000 vdc (camera tazer)? If not how can I do this?

[ARJOON]

INSTEAD USE CAMERAs you can get approximately 60kv

[Mudbud]

uhm, Ive only gotten 300VDC outta camera circuits..

[Adam Manick]

Wouldn’t 60kv volts arc across the transformer and destroy it. I highly doubt you can get that from a camera flash. Even a neon sign transformer can’t put out that much.

[ARJOON]

yeah i burnt mine instantaneously. that was crazy. when i opend the transformer. wire in the secondary was burnt. it was like dust.

[Adam Manick]

Did you measure the voltage before it burnt out?

[ARJOON]

no i did not that was quick.

[jules15]

I don't understand.. I'm already using a camera

[ARJOON]

on your first circuit in the camera. remove the capacitor and instead place this transformer from another camera.(must be alike)

solder pin 1 to one lead of the cap outpuit
then solder pin 3 to the other lead.

then you will get an output more than 60kv (more than enough to kill) in pins 4 and five.
i've never tried but if it works pin 4 and 5 will be arcing a lot.

[ankitgarg2005]

I need to convert a 6v 4.5A battery into 12v that can give around 2A or more current
any schematic? Voltage doubler circuits on the web gives around 100mA which is not sufficient for motor driving. Thanks...

[ARJOON]

try using an oscillator n rewind a small 1:1 transformer to 1:2 n u may get it

[ankitgarg2005]

Can I do this with some IC ? I don't have much knowledge of transformers.

[ARJOON]

use the so known 555oscillator. amplify through transistor or mosfet which in turn will drive the transformer to double the voltage. don't forget to rectify the other end

[ankitgarg2005]

sir can u provide me the circuit diagram please.

[ARJOON]

u can use this circuit. but reduce the frequency to about 40-75Hz. this will enable you to use a normal transformer.

[jules15]

Ok thanks a lot ill try it

[anvit]

How did you calculated the value of the capacitors .?
can we replace them by any other values ?

[V1x0r]

Soooo...because I was having a hard time with initial directions I made this little "Solder directional based off of MOAL's pdf.

Thanks for the Tut btw!!!! I'm excited to get this finally put together!

(Q1a - L1a - R1b) --> power Input
(Q1b - Q2a)
(Q1c - C1a - R2a)

(Q2b - R1a - Q3a - C1b)
(Q2c - C2a - Q3b - R2b)

(L1b - D1a (side w/o black strip) - Q3c)

(D1b - C2b) --> power out

Please correct me if i'm wrong.

I don't know which ends connect to the grounds. >_<

[V1x0r]

(Q2c - C2a - Q3b - R2b) connect to a ground. Correct?

[ARJOON]

i messed up with datasheets on my pc that is why it got all screwed up now this new pcb design is the good one.

[ARJOON]

I AM SO SORRY. i made it now and tested it. this now is sure the good one. i forgot to add wires and the transistor pinout was incorrect. now this pcb is nice and no error.

[silencekilla]

Does it charge capacitors? and we have the same brand and style multimeters just different model types

[krmartin3]

yes, but since there isn't much current iit can be slow depending on how big of a capacitor your using.

[silencekilla]

big reffering to volts or uf?

[krmartin3]

uF. The higher the capacitance in farads the slower it is to charge which is a drawback but the benifit is it will take longer to drain when you add a load to the other end.

[silencekilla]

would you be able to post one that will charge up to 1 farad or if not what about 1/2 Farad?

[qazwsx755]

Great Instructable! I have 2 questions for you how many amps dose your DC Boost Converter output and how many Hz is your RF choke?

[krmartin3]

sorry for taking so long to respond. i tried to measure the current at the time and it seemed to low for me to measure but doing a quick calculation i estimate no more than .04 amps. and i think my rf choke is rated at 1 mhz but i could be wrong, its the one you can find at radioshack or their website.

[ARJOON]

and here is the pcb. if the inductor don't fit. mount it vertically. it works great

[ARJOON]

hello there here is a neater shematic

[devinmccloud]

I believe it is the amperage that kills not voltage!