Power Consumption on Min, Medium and Max Load


#1

Hi guyz,

Does any one have power consumption details or document for dragonboard410c. please post the same.

thank you very much.

Thanks & Regards
Pratik vasagadekar


#2

Hi Pratik:

Good timing with your question. Over the last few days I took some ‘crude’ measurements. It depends on which operating system you are running!.

Android idle ~0.6Watts
Linux (Ubuntu 15.09 release) idle ~1.3 Watts
Linux loaded ~4 Watts using “stress -c 4 -i 4 -m 2 &”

I measured these values by putting an ammeter in series with the DC power jack, taking the current reading (in amps) and multiplying by 12 (volts) to the consumption in Watts. The Ammeter readings are not very stable (because the power draw is constantly changing as the system does things), so the measurements are not very accurate, just me averaging the readings in my head.

I strongly suggest you measure your own power consumption using your peripherals and applications. The ‘idle’ numbers are with the display running and active, this is not a sleep power which obviously could be much lower.

Warning!: these numbers and are affected by many variables. I had bunch of stuff attached to the 410c, a HDMI display (it does draw power, but I haven’t measured how much), a mouse and keyboard (again how much power do they draw?), a 64GB SDCard as swap space, and a 96Boards Arduino mezzanine board (more power). The software obviously makes a huge difference as you can see by comparing the Android and Ubuntu idle numbers.

I am working on an app note on how to measure power which I hope to publish in the new year. Since the SW mates such a huge difference to the system level power, I think it will really help the developers if they can easily check that their changes don’t increase power consumption.

Full Disclosure: I am an employee of Qualcomm Canada. Any opinions expressed in this post or any other post may not reflect the opinions of my employer.


#3

Thats nice to hear from you ljking.

just to be sure, does Android supports H/W Acceleration. Thanks for the info about your readings. In case you have readings when your android goes on medium Load. 2 USB + HDMI @ 1080p then let me know.

What you said is correct, a small change in SW may make huge difference. I am switching to Dragonboard from Raspberry Pi because of Android 5.1 support and Inbuilt GPS. though its costly for a commercial product. Plus the Operating temps are very nice.


#4

Sorry, I don’t have more Android numbers, but I strongly recommend that you measure power consumption while running your applications in your system. Anything I measure will just lead you to wrong conclusions.

Android supports all of the HW acceleration.

If you are building a commercial product you might want to look at the 410 SOMs (System on a Module) offered by other companies, they offer support, customization, and smaller form factors that the 410c board.

Full Disclosure: I am an employee of Qualcomm Canada. Any opinions expressed in this post or any other post may not reflect the opinions of my employer.


#5

hey,
can we optimize power consumption by putting peripherals like USB, sensors like temperature?
and can i draw power from 9v battery for dragon board , will it work properly?


#6

I think you firstly need to check the battery characteristic, including max current, e.g. ENERGIZER LA522 9V [1] battery supports 1000mA maximum. Exceeding this value, voltage tends to fall down. 9V at 1000mA corresponds to a maximum instant power of 9W. This seems to be enough regarding reported idle consumption(1.3W) but I’m not sure about the Dragonboard peak power, especially at boot.

An other point is the capacity, a 9V/1000mAh battery corresponds to a capacity of 9Wh which allows you to power your board during about 7h (9Wh/1.3W) assuming board stays in idle state.

[1] http://data.energizer.com/pdfs/la522.pdf