I found an article http://www.instructables.com/id/Worlds-Smallest-Power-Supply-/ I was thinking about making something similar to this except with a constant voltage and try to up to 3 amps. Waiting on parts now!
@PeterRobinson If you replace the DC-DC boost into the small one I linked earlier it should perfectly fit. The one in the article is only doing max 2A (1A normal).
Awesome! I'll order that part as well and see what we can make. Thank you so much for your input! I do appreciate it and I'll let ya know how it all turns out!
@PeterRobinson May I ask if you have made other changes, like battery size, and perhaps increasing from a single cell to series? I would advise against the set-up as shown in that Instructable. The current draw of the 3.7 volt battery would be around 10 amps if the UDOO X86 was running at 3 amps (the 12V power adapter in the UDOO shop is rated for 3 amps, so I'm using that as the basis of the power draw calculation). A 850mAh battery would discharge in about 5 minutes on that type of draw. And you would not be able to keep it going with a USB power supply, as they are 2 amps or less, depending on whether it is a dedicated charging port. I may be wrong in my calculations, as I still have a lot to learn. Here's how I calculated it: UDOO X86 power = I x V = 3 x 12 = 36 watts Battery current = P / V = 36 / 3.7 = 9.73 amps
You're right. That sure is a whole lot of current and would drain the battery as well as create heat. It's currently the best lead I have but I'm hoping to get some great ideas from anyone willing. I only know just enough electronics engineering to be dangerous and to know how much I don't know. I have yet to purchase the UDOO X86 board itself but I do not intent to modify it in anyway other than removing or extending certain components like the ethernet port..etc.
You have to calculate the capacity of battery by calculating the current @12V and multiply that current times the hours you want to run the Udoo X86 (including display etc) Say Udoo X86 uses avarage 1A (there are more figures available somewhere here on the forum), your 10" display uses 0.58A and you want to run it for 3 hours. Battery capacity to buy is 3x1.58=4.7Ah (or 4700mAh) *at 12V *(edit)
One UDOO X86 project that I considered, was to create a shield with a surface mounted three cell battery holder, wired in series, for 18650 sized LiFePO4 batteries (safer than a LiPo - I would have probably have inadvertently created a Samsung Galaxy S7 phone if I used one of those). Then using a chip like suggested by @waltervl to manage the power. The one I was specifically looking at was the LTC4015, because I was going to monitor the power via I2C and liked the fact I could change my mind with battery choices.
Another project I was considering, was creating a shield with a USB Type-C port with power delivery spec and no data, for powering the UDOO X86. The PD spec allows for up to 100 watts and I'm fairly confident that UDOO will have included a Vin pin on the X86 header, so the shield could input the power directly into the 12V rail. I have so many project ideas, feel free to copy and complete them before me! I'm still working on my case from last year. Access to the right tools is the biggest hurdle I face - I think I should move somewhere that is closer to a hack/maker space.
Hey guys just a recap of the goal.. I'm still looking at parts and deciding what we need to make a portable power supply for the UDOOx86 So what we need is a portable battery/power supply that can supply a steady 12v 3a to the UDOO board. All peripherals will be powered through the board itself via USB so we need to be sure it can supply power to many peripherals for the same amount of time a smart phone runs for. So far I know I need - The Battery itself - Still not picked out. I still need to calculate Voltage and mAh Could this be used? https://www.amazon.com/dp/B071J1C6Z8/_encoding=UTF8?coliid=I5UA8474LMWNP&colid=2IEQOK23S3NWH&psc=1 possibly disassembled in some fashion Charging and step up circuit.. Helpful Guides https://muxtronics.nl/powerbank.html http://www.instructables.com/id/Worlds-Smallest-Power-Supply-/ Step UP Buck Converter https://www.ebay.com/itm/DC-DC-Boos...ter-XL6009-Module-Solar-Voltage-/161270864741 Charge Circuit https://www.amazon.com/Makerfocus-C...1512865585&sr=8-1-spons&keywords=tp4056&psc=1 Screen/Display https://www.amazon.com/dp/B0749D617J/_encoding=UTF8?coliid=IG5VD6O51O43B&colid=1M7GYCA0V8B3Q&psc=0 I appreciate greater knowledge and input. Please tell me if there is a better option.
So if this is right..If I have a 3000 mah battery on 3 amps it will work for 1 hour. Would the udoo board contantly draw 3000mah?
Correct! Though when selecting a battery, make sure the C rating is adequate. The Battery University has a good explanation on this and other battery topics - http://batteryuniversity.com/learn/article/what_is_the_c_rate 3 amps is the figure mentioned by various members, because it's the amount of amps the recommended power adapter can provide. It covers the possible current sinking loads, like two SATA devices (M.2 and wired SATA connector). A wireless M.2 card, and the USB ports that power devices. If you do not have those loads connected, you will use much less power. The CPU only uses 6 Watts
@PeterRobinson For a clean, compact power supply build, I'd suggest designing a shield, using a programme like KiCad (free open source) and using a service like OSH Park to get a bare PCB (doing a rough calculation, it will be about $30 for three bare PCBs). On the shield, have a: DC jack socket A three cell battery holder like this: http://www.ebay.co.uk/itm/like/152384279642 (though not necessarily this one, as I did a quick search and it might not be the best option) A charging IC and supporting circuitry Male header pins The shield's power output can probably go straight into a header Vin pin, so the existing DC input on the board will no longer need to be connected to a supply. The schematic is not due until shortly after the board is released, which is required to confirm this! Edited to add - If anyone is considering this option, please make sure you follow precautions, for example, use a 12 volt dummy load first and not your UDOO X86 board! Also, please create a thread in the project area of this forum. Would be good to see what members have made
a little off topic but does anybody know what is the temperature of the CPU under 100% load and full TDP of 6 W if only passive cooling is in use without the fan?
@dr. Chernobyl It's a difficult question to provide a reliable answer on, as passive cooling is affected by numerous variables, ranging from ambient temperature to sea level. When community members start receiving their boards, hopefully a few will share their experiencing with cooling. If you post this question in a couple of weeks as a new thread, I'm sure you will get some good answers
excuse me, I should have specified that I mean temperature of the die under standard atmospheric conditions and with heatsink in free air without an enclosure thank you anyway, we will wait then for real life tests to find out
The Intel SoC datasheet might help in the meantime - http://www.intel.com/content/dam/ww.../pentium-celeron-n-series-datasheet-vol-1.pdf Though, it's more along the lines of "this is the temperature I do not like " I'm not very good at thermal calculations. It's something I should learn to do though - Would be handy when working out if I can place an IC on the underside of a PCB. Last week, I ordered a non-contact infrared thermometer, which I'm looking forward to experimenting with.
I'm assuming it's the same requirement than an old laptop battery (it's X86 with the same connection and it was more demanding before) I read an instructible over recylcing laptop battery. Basicaly you test your cell by charging them and measure voltage one week after. http://www.instructables.com/id/REUSE-YOUR-OLD-LAPTOP-BATTERY-TO-MAKE-A-POWER-BANK/ In the comment, they say the challenge is not letting the cell's voltage below a value. Then why not reuse the battery's controller also ? Even better, Why not swapping the motherboard with an udoo X86 and join me trying to connect laptop LVDS screens ?!
@Laura Thank you very much! So a 10000mAh battery with a 1C rating would take one hour to discharge at 10A? is that right? It will take me more time to deeper understand how long it would take to charge and more math for me to figure out how long it would take to discharge a 1C 10,000mAh battery at 3A but I think I get the concept. I'm leaning more towards a smaller 3.7 thinner battery with a higher mAh and use some dc to dc circuitry to step up the voltage and current. We can still make that a shield though instead of a battery and circuit that just plugs into the DC jack. whichever looks and feels better for design. I'd like to keep the pins open for that we can still use them for anything else we may need to add.
Yes* and with a 1C rating, you cannot discharge the battery any quicker than an hour, so will be limited to a 10A load on a 10000mAh battery. *There are other factors that determine the battery's life - It will have an internal resistance, and will be affected by temperature, so the life calculation is not just 'life = battery capacity in milliamps per hour / load current in milliamps. I should have made that clear earlier, sorry. So a 10000mAh battery with 10A load current, would probably have a life of 40 to 50 mins. While learning about batteries, I recommend not using Lithium-Polymers (but if you do opt for this type of battery, make sure it contains a protection circuit). Lithium-ions are a safer option, though they are not nearly as compact.
