It's tempting to make portable Arduino projects with the usual board feed in a battery pack via the DC socket, however for lower-power applications a fair amount of energy is wasted in the voltage regulator, unnecessary LEDs and other parts of the circuit. Taking this into consideration, the folks at the "Open Home Automation" website have documented neatly how to create not only a minimalist Arduino-compatible circuit on a breadboard using a pre-programmed ATmega328P - they continue further with the power-saving theme by explaining the JeeLib low-power functions library and the various sleep functions within.
The results are quite good - with normal operation the bare circuit consumed around 6.7 mA with normal code - and 43 uA with the library. Outstanding. For more details and the required code, visit the OHA website. And for more, we're on twitter and Google+, so follow us for news and product updates as well.
If you're prototyping Arduino projects on solderless breadboards, blown the MCU on your board, or making your own such as the timer game mentioned above - save time and hassle with our new ATmega328 microcontroller pre-loaded with the Arduino Uno bootloader:
It's the same one as found on our Eleven, KitTen and the original Arduino Uno, plus it has a very useful pinout sticker attached to save confusion when wiring it up. So for more information and to order, click here. And we also sell the stickers!