snapster:
Hi, I am working on a low-power arduino-based project, and I'd like to use a lipo battery for the job. As it is a low-power situation, I'd like to bypass the on-board voltage regulator on the arduino. Also, I'm considering using one of the 3.3V-8 MHz arduino pro minis.
But a lipo starts at 4.2 V. My question is: is that too much voltage for a 3.3V arduino? Am I better off using a 5V arduino?
I'm a little confused about all this, because on the one hand, I see stuff about the ATMega328 working down to 1.8V...If there's such a range, why do people refer to a 5V arduino and a 3.3V arduino?
Less confusing when you know that the ATMEGA has an operating range of from 1.8V to 5V. You get to choose what voltage you run it at. As the voltage is lowered, the maximum specified operating frequency falls too.
So at 5V they are normally run at 16Mhz and at 3.3V its 8Mhz.