SparkFun Forums

[mac]

I was searching for a cheap and quite efficient way to power 3.3v circuit from a li-ion battery.

I found Maxim AN438 which is very interesting.

I think it can be a good start for a 3.3v li-ion psu breakout and a good addition to li-ion charger breakout. Maybe adding a auto-shutdown circuit also.

[mac]

LTC3785 is also a good candidate: buck/boost topology, but it requires external mosfets (3) and is a QFN package.