Well, after all the work that joelucid has done perfecting ListenMode and convincing me that we could, in fact, run for a significant amount of time using CR2032 batteries (see thread
https://lowpowerlab.com/forum/index.php/topic,1136.0.html), I've finally got my Tiny TH Mote operational. This runs from a single CR2032 battery with an overall diameter of just 26 mm. The device is layered with ATMega328P and Si7021 TH monitor on one side, the RFM69W radio on the reverse side, and then, stacked behind the radio, is the CR2032 battery, for an overall thickness of slightly less than 13mm.
I'll be posting the design files, some code, referencing the new RFM69_ATC library, and showing how I intend to package this cute little thing. I'll also track battery life data here. Meanwhile, just to show that it exists, here are a couple of photos... The second one is the pogo pin board I use to do initial program load into the device.
Enjoy!
Tom
UPDATED: 9/11/15 Added Eagle Design Files. The only change from the original files is that I increased the size of the pogo-pin holes to accept the pins themselves and make a larger target for the probe.