Increase Voltage/Current using transistor

[Z4ZABI]

hi all, I am absolutely new to learn electronics. I have been playing with LED's DC Motors and similar things found in toys during my childhood... but now i want to learn electronics for some basic use.

I was searching to increase the voltage of a 1.5v battery... for example i want to light up an LED with just 1.5v AA battery... so i found it can be done with transistor easily... one thing that is confusing me is "Which transistor should i use and how ? or any transister would work ?"

I have some C945 transistors... is it of some use in my problem.

 

[alexan_e]

I'm afraid it is not that simple , a boost (step-up) converted needs a complete circuit , a transistor can't do what you want
Boost converter - Wikipedia, the free encyclopedia

Alex

 

[mister_rf]

Yes, need to use ''the joule thief '', an electronic circuit that lights up a Light Emitting Diode using just a single AA battery
Make a Joule thief.
Joule Thief Single Cell LED Driver

 

[xuexucheng]

I can tell you the main function of the transistor.
It can amplify the signal but with the power supply.
generally the output signal can not go beyond the power supply.

 

[mister_rf]

It's true that a simple transistor fails to, but combined with a small coil, the assembly described as a ''Joule Thief'', will do the trick. Perhaps this is the idea that left the question.

 

[Z4ZABI]

Okay... I don't understand much about it till now... hope I would in near future... thanx everyone for guidance...

please guide me to learn about Simple, Interesting and easy circuits...(LEDs, Motors, Fans, Speakers etc...) so that I can have some fun with them while learning...

 

[mister_rf]

Did you read those links ?
You have there all needed details how to build such a very simple device.
check here:

Make a Joule thief.

and here:

Joule Thief Single Cell LED Driver

 

[Z4ZABI]

Yup! i did... But i didn't actually understand the coil transformer or similar thing... anyway... i will keep on searching for the solution i found some time ago... and will post here fo help...

Thanh for cooperation

 

[mister_rf]

You need only a small ferrite toroid.


See a picture illustrating how the dots on the circuit symbol for a transformer related to the toroid windings in the joule thief circuit: