I've tried the narcoleptic library and it does bring the power down from about 30mA to 22mA but I'm looking for the extremely low power states. Any help will be appreciated.

The AVR microcontroller itself is capable of extremely low current operation, however the power consumption depends on a lot of factors:

- First, what outputs are you driving with the Diavolino? If your 22 mA is dominated by sourcing current, the code won't be able to do much about that. Running an LED can take up quite a bit of current, for example. The AVR itself, at 16 MHz and 5 V uses about 7 mA. Where is the rest going? It's possible that the narcoleptic library is doing just what it should-- 30 mA and 22 mA are about 7 mA apart.

I could walk you through any number of procedures for using lower current-- but I suspect that the answer is right there.

I'm using the Diavolino board. For the test NOTHING else connected to it. The LED is turned off.

Oh, and btw thank you for the quick response!

Well, that's surprising.

What is the configuration of the Diavolino? 5V/9V? Regulator? How and where are you measuring the current? Is anything hooked up to the Diavolino when you're measuring-- like the USB-TTL cable, or an ISP cable?

When I removed the serial lines back to the FTDI usb to ttl serial and retested the power dropped down to about 160 micro-Amps. Still higher then I wanted--but much better than what I was seeing and very acceptable. Running at 5 v and 16MHz. Thank you.

>Running at 5 v and 16MHz.

Power consumption scales almost linearly with clock speed. That AVR is capable of running down to very low speeds. If you can run at 512 kHz, for example (off of the internal RC oscillator, divided down), you may be able to approach 1/32 of that power consumption. Certainly worth considering. Also, at lower clock speeds you can run on lower voltages, which also scales down the power consumption dramatically.