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I've never used the R. Pi before, but am considering it (model A) for my application. The main attraction is the hardware H.264 encoder, but not the power consumption :(

I've read about a few power savings methods like using a switching regulator and turning off the TV & HDMI outputs. It seems some people have achieved around ~130mA according to here.

I still consider this too high for a battery powered application, which doesn't need to be on all the time. Can I do a suspend to RAM and how much power will this use? Is there a wakeup timer I can use to resume?

I've used microcontrollers before and know you can cut the power 5x (from 1mA to 0.2 mA) by putting it into sleep mode. Even when it's not asleep, you save power by running the wait for interrupt instruction, and disabling peripherals. Does anyone know if there's anything to gain by doing this?

Update: I found a very detailed and useful power data for the AM335x used by BeagleBone here. Thank you very much for publishing it. Even the standby mode (16mA) would be good enough for me. The biggest power consumers are the CPU and the DDR (not clear what VDD_CORE includes). Can I achieve something similar for the R. Pi?

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  • I don't know about the model A but the model B draws about 125 mA from the power supply even when powered down.
    – joan
    Jun 24, 2014 at 21:04
  • @Yale_Zhang Did you ever find a similiar "Power Consumption Summary" for the pi?
    – Ted Taylor of Life
    Aug 30, 2016 at 20:14
  • @TedTaylorofLife I could go to my local San Jose Broadcom office and beg them for the SOC documentation, but that would be naive. Unbelievable! TI documents every register in their SOC except for the proprietary GPU, while Broadcom barely documents anything. Are they that paranoid about giving away secrets or getting sued for infringement? I ended up using STM32F4 and now STM32F7 (has a JPEG encoder!). Fortunately, ST makes excellent documentation for their MCUs.
    – Yale Zhang
    Sep 14, 2016 at 21:28
  • @YaleZhang Lol . Great to hear! Thanks for getting back to me.
    – Ted Taylor of Life
    Sep 15, 2016 at 14:05

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The RPi is definitely not made to have the lowest power consumption making it not the best choice for mobile application. As is already pointed out there are a few minor tweaks (disabling the HDMI or if not needed USB) to save a little power. Replacing the linear voltage regulator with switching regulators also helps a little. But still there is no real power-down mode and the RPi will consume quite a bit even if halted this can by no means be compared to power-down or sleep modes of microcontrollers.

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  • What would you suggest that consumes little power that can run Linux, connect a camera, and has lan?
    – Ted Taylor of Life
    Aug 30, 2016 at 20:16
  • @TedTaylorofLife Sorry, I am not aware of a good comparison of the power consumption of Pi-alike boards. It also depends on what you call little power, might be a Pi is already the thing you're looking for. Using the Pi with grid power might be considered low power as is. The lack of hibernation or sleep modes is more likely an issue for a mobile applications running of batteries.
    – Ghanima ♦
    Aug 30, 2016 at 20:33
  • No worries at all, thanks for the response. If anything comes to mind please let me know.
    – Ted Taylor of Life
    Aug 30, 2016 at 20:38
  • @TedTaylorofLife sounds like a good question in its own right. Since it mainly covers non-Pi entities it might be off-topic here, maybe electronics.stackexchange.com is a better fit.
    – Ghanima ♦
    Aug 30, 2016 at 20:43
  • Maybe I will =)
    – Ted Taylor of Life
    Aug 30, 2016 at 20:51

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