I want to make a LED driver for a while LED (1W, 350mA, forward voltage: 3.1-3.4V). I find two circuit on the Internet. However, I don't know advantage and disadvantage of them. I hope you talk for me should should choose which. Thank you very much^^
Firsly, the circuit using IC LM317
Other one,
Firsly, the circuit using IC LM317
Other one,