1.2 to 5Volt self oscillating

[grittinjames]

Hi
I am seein 1.2V to 5volt mobile charger. They havnt used any costly IC. They used one small mosfet and some general component.
Do any one having similar circuit?
Please help me to find one
Thanks
Grittin

 

[FvM]

"Costly" ICs or not, they at least need to implement a boost converter, using an inductor/transformer and an oscillator, possibly a self-oscillating switching stage. Achieving low quiescent current and high efficiency is kind of a challenge for a simple low part count boost converter.