DIY Voltage step up

I really need to step up my 3.7v to at least 6.2v. I don't want to spend money because boost converters in my country are STUPID expensive. You can give me a schematic. What I do have is: IRF520/510 Mosfet, Transistors (bc557/547/2n2222/2n3904) and a lot of capacitors and resistors.

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Lots of schematics on Google. Do a search, see which fits your specific application best.

I can tell you already you miss at least two essential parts: an inductor and the a controller IC. Well, it can be done without controller IC (you can build a simple circuit to run a 3.5V white LED off a single 1.5V battery), but you need an inductor at the very least.

Oh, been there; done that. [These](http://CHENBO MT3608 DC-DC Step Up Power Module Booster Power Module 2A For Arduino) handy things are available. I didn't realize there were ready made boards until it was brought to my attention (via arduino forum). I remember having to build an LRC circuit to achieve my needs...

Depending on the current requirements, a simple voltage doubler circuit may be enough