Go Down

Topic: Low Power Arduino (Read 3 times) previous topic - next topic

48X24X48X

Sep 06, 2010, 06:07 am Last Edit: Sep 07, 2010, 04:55 am by 48X24X48X Reason: 1


This is our attempt to make a low power Arduino variation board. Some feature of the board:
  • It uses the "breadboard" (ATmega328 on a breadboard (8 MHz internal clock)) as the board option in Arduino IDE 0018.
  • Utilizes full SMD components to reduce the cost of assembly.
  • Ultra can be powered by either the USB, external DC source, Li-Ion/Polymer or all of them at the same time.
  • Runs on 3.3 V rail as most low power interface runs on 3.3 V rail or lower.
  • A low power 32.768 kHz is present to allow the board use it as a asynchronous timing source during power safe mode. This removes the need of an external dedicated RTC IC.
  • Microcontroller - ATmega328P-AU
  • Clock - Internal RC 8 MHz oscillator
  • External DC source range - 7.5 - 36 V, 2 A
  • Battery - Lithium Ion or Lithium Polymer with temperature monitor for charging
  • Battery charging - Maximum 500 mA charge current
  • Buck-boost converter stage for usage of input voltage lower than 3.3 V
  • On board temperature sensor - MCP9700 connected to ADC7
  • Battery voltage monitoring - Connected to ADC6
  • USB port protection - 500 mA resettable fuse
  • Analog reference voltage with LC filter
  • Indicator LED connected to digital pin 13
  • Has Arduino standard breakout pins at the bottom side using SMD 2.54 mm headers
  • Dimension - 55.88 mm x 68.58 mm


We tested the 1st PCB attempt in terms of functionality and found out that we forgot to supply the MCP9700 sensors with supply,  :o. Have yet to measure the current consumption especially during power save mode but we hope it goes near the design specifications.

Schematic Revision 1.00

Udo Klein

Where could we see the schematics? Preferably in Eagle format.
And where can we buy this?

Udo
Check out my experiments http://blog.blinkenlight.net

raalst


Coding Badly

Quote
Clock - Internal RC 8 MHz oscillator

Calibrated?

48X24X48X

#4
Sep 07, 2010, 05:14 am Last Edit: Sep 07, 2010, 05:16 am by 48X24X48X Reason: 1
Quote
Where could we see the schematics? Preferably in Eagle format.
And where can we buy this?


I just uploaded the schematic. I did the design in Diptrace because it's easier for me. I'm not sure whether I would sell this but it depends on whether people are interested. :)

Quote
for low-power have a look at this development too :
http://news.jeelabs.org/2010/09/03/jeenode-goes-solar/
http://news.jeelabs.org/2010/09/02/sending-packets-without-battery/
and
http://news.jeelabs.org/2010/09/06/running-off-a-single-aa-battery/


I'm crazy about low power stuff as it is so important in my 9-5 job.
The external 7.5 V to 36 V input was meant for solar panel but needs a Li-Ion/Li-Pol on top of that. :) Thanks for the links.

Quote
Calibrated?

I'm looking into that but it might need to load the calibration values into the OSCCAL register during power up from any storage like the EEPROM or flash in the sketch itself. But we tested the serial communication up to 1M, it works fine but haven't test against temperature variation yet. I'm quite sure it needs calibration as LilyPad itself change from Internal RC to the external resonator probably due to this same reason.


Go Up