Ooh I hadn't considered AAA. Totally forgot they existed. Thanks! I don't want to use Li poly since they're rechargeable and I don't trust the friends I plan to give this device to to properly maintain a rechargeable battery. The buck inverter is way too complicated for a small project like this. Two AAAs in series is perfect. Sorry for not trimming. Replying from phone. On Monday, May 30, 2011, Michael Watterson wrote: > On 30/05/2011 09:36, V G wrote: >> Hey all, >> >> This is regarding my optical guitar tuner idea, where a circuit will be >> powered from CR2032 coin cells. The circuit will be drawing (I'm guessin= g) >> around 30-50mA due to 2-4 LEDs pulsing at sound frequencies. >> >> I know that CR2032s are designed for around a 1mA continuous draw, and u= p to >> 10mA pulse draw, but people make LED keychains out of these things all t= he >> time and those LEDs draw 20mA or so continuously. I want to power the tu= ner >> with these cells, but I don't want the performance of the batteries to >> degrade as much due to the relatively high current draw. Therefore, I'll= be >> putting these batteries in parallel (about 3 or 4 of them in parallel). >> >> Is this okay? What kinds of issues will there be? Will there be issues o= f >> the batteries charging into each other? Things like that? > > why not in series with a buck inverter? > > They are primary cells. Maybe not good in Parallel. > > Alternatively if you need 3 or 4 maybe you should be looking at a > rectangular LiPoly, or 2x AAA Alkaline or something else. > > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .