Power consumption

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1

Hi,

_*Introduction*_

I wanto to know if the "BeagleBoard" is good for my embeeded system. My system will be autonomous (photovoltaic system), so nobody will be able to connect or disconnect it since the system will be in the Artic alone. The aim of my system is a GPS receiver that will record some hours of data every day. So, I want to:

1) work at the low power consumption when the system will be ON (GPS receiver recording data), and
2) work in "sleep" or "idle" or some low power mode of the ARM processor when the system will be OFF (GPS receiver not recording data)

_*Configuration

*_BeagleBoard (running a full featured Linux version when the system will be ON, for example, Debian) + ZIPPY board (because I need more than one RS232 port)

*_Questions_*

I know that the power typical consumption is 1.5W when in the UBoot mode (so, when my system will be ON). It is a lot of power since I need that my BeagleBoard + ZiPPY board consumes about 0.4 W when they will be ON. I know that the consumption depends on what you have running and connected (the Ethernet and USB are very power hungry) and that the processor has voltage and frequency scaling that can be used to control the power (for example, you can cut the frequency to say 100MHZ and reduce this power greatly).

Also, I know that the OMAP3530 has sophisticated methods for power control so you can switch off most of the modules that you don't need.

So...

*Question 1:* What is the estimated power consumption of the Beagle Board (running Linux) + ZIPPY board at the low frequency that you can scale the processor and switching off the ethernet, USB, DVI-D, S-Video, Stereo Out, and Stereo In ports (modules switch on: RS-232)?

Note: I have done the test with another ARM board (TS-7260) and the result is 0.4W (running Debian Linux from a SD card + three RS-232). The problem is that I don't have a BeagleBoard to do the test.

*Question 2:* As you know, I need to put the processor in a low power mode ('idle' or 'sleep' or other) when my GPS receiver won't record data. What mode can I put my processor in to save power? What is the consumption of the BeagleBoard + ZIPPY board in this low power mode?

Thanks,
Ismael

2

Ismael,

Beside the power, I would check if the board will work at Artic
temperatures... The energy you need to get a stable temperature will
probably require more power the board itself :slight_smile:

Wkr,
Joep

-----Oorspronkelijk bericht-----

3

Ismael,

Maybe I can recommend other ARM board, like the Technologic Systems
7000 series, it has a broader temperature range than the BeagleBoard,
with much lower performance but you don't seem to need much. It runs
debian perfectly.

Maybe you can use directly a Microcontroller like PIC or freescale,
they consume next to nothing and then the your max power usage will be
the GPS module.

4

Oops re-read your email and you already considered a TS board. Sorry,
shame on me! :stuck_out_tongue:

5

You're the only one able to reply to this (truly) interesting
question.
How to switch off cortex-a8 components & which one ?
How to tune frequency ?
How & How much time to wake up ?
What is power consumption ?

If you say you need max 0.8 W that will not be easy wihtout tuning the
cortex frequency :).

6

just recording a slow 4800bps gps requires little overhead. It
seems to me there would be far lighter hardware to use than a
BeagleBoard. Besides, beagles aren't Artic adapted like huskies :wink:

jmtcw:
Don Lewis

7

Maybe you can use directly a Microcontroller like PIC or freescale,
they consume next to nothing and then the your max power usage will be
the GPS module.

I connected a GPS unit to the Beagleboard RS232 port. The GPS unit I use was declared to require "75mA @5V" only, but in the real field it proved to be 200-250mA more than that (!!!).

If you only plan to save GPS data either on a memory card or via wireless, you may consider other simpler solutions; a full-fledged Linux system (like the Beagleboard) seems a bit overkill.

alf