If it wasn't clear by the numbers, the 19v dcdc-usb consumes 0.08A itself with nothing connected. Doing 5v appeared to be at least 90% efficient.Quote:
It's not clear if you're still fighting to get the lowest power possible, but I can offer a couple of potential pointers:
If you're not already, you can supposedly save a ton of power on the igepv2 by installing a "tickless kernel" which will let you take advantage of ARM in the 0mhz state. I never actually did this, but
I've been using a 30 watt solar panel, and it is just nowhere near powerful enough to keep a FitPC2 (my quick and dirty semi-low-power car pc) running (Atom @ 5-8 watts)
The dcdc-usb claims to have >90% efficiency when regulating from 16volts to 12 volts at 2 amps. But I'm suspicious as to why the manual doesn't state any other voltages/amperages. You may want to measure how much power it's burning itself.
Yep! I was going to check up on your worklog as well. Hope you post an update soon.Quote:
For the USB hub and the igepv2 which run on 5 volts, the most efficient and easily accessible power supply I can find is this: http://www.sparkfun.com/products/10104
It's Tiny, $29.95 8v-42v input, 5v/3.3v output, 85-90% efficiency, but you lose all the fancy features of the dcdc-usb, not sure how much they matter to you though.
Hope you can find any of this useful.