Okay, I’m still around here. Somewhere. 😉
If you haven’t heard, there are some really cool&tiny stepdowns: MP2109DQ. I got a bunch of ’em nearly as cheap as AMS1117 linear lowdropouts.
These are synchronos stepdowns, 2 of them in one package. Unlike some bulky LM2596 – no diode needed. Only 2.2uH inductor and a few capacitors and resistors.
Cool things come in small packages: it’s packed into QFN10 (3×3 mm).
However, I didn’t want to put them on my BIG project without testing, so I decided to throw up a small board to test it, as usual. And also check, if my “press’n’peel” and “soldering ninja” skills are high enough for QFN10 (The first time I’ve done that to QFN, actually). Result was a success, from the very first time. Obligatory pics follow, more under the cut.
These thingies are hard to route in one layer. I had to route quite a few tracks between the sm0603 pads, and still had to throw two wires to interconnect all GND polygons.
And now the tasty stuff:
QFN10 for kicad’s PCBNew
EESCHEMA symbol for MP2109DQ