Hi,
I'm trying to design a switch mode step down buck regulator on my ATmega-based microcontroller board that will take 5-12+v from a LiPo or other power source and convert it to 5v with max current 1A.
I'm new to the field of power supplies/regulators, so I don't yet know exactly what would work well and what wouldn't.
I've looked at TI's TL2575 ICs, which are 1A "simple step-down switching regulators." Only four external components are needed (inductor, 2 caps, schottky diode), and it's 85+% efficient. The problem, however, is that it requires a big 330uH inductor that is expensive.
I then moved on to looking at another TI chip, the TPS63061 (kind of hard to find...just released in Dec. 2011). It is a buck-boost converter with 2A max current. This will allow for an input lower than 5v, as well as above it, so it would work great with 1/2-cell LiPo batteries. It uses a 1.5uH inductor, some small caps, a resistor, and a pretty big 66uF ceramic. Overall, the footprint is much smaller, but the total cost is a bit higher. Here's a basic schematic.
I've also been on WEBENCH and desiged a 6-18v input, 5v/1.6A output regulator with the TI LM20333.
What design would you suggest?
Thanks for the help!
Michael
