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I want to power this board with a 3.7V LiPo battery (due to small form factor) such as this.

Would I need a step-up DC converter or something? And where on the BBB would I connect it?

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The BBB has a specific, unpopulated, header just for a single cell(3.7V) LiPo, charger and all! It sits just behind the 5VDC barrel jack, 4 pins labeled TP5-8. Page 41 of the A5A manual shows the pinout. Keep in mind that powering from a 3.7V Lipo via the battery pins will prevent the USB Host port from providing 5V power.

This guy has a small tutorial on how to wire it up: http://www.element14.com/community/community/knode/single-board_computers/next-gen_beaglebone/blog/2013/08/10/bbb--rechargeable-on-board-battery-system

The BBB has a built-in power management IC (PMIC) based on the TI TPS65217C device. This device contains multiple switch-mode regulators and LDO regulators to provide all voltage levels needed for the entire board.

The IC also contains built-in battery charging capability.

Apart from the USB requirement of 5V, there is no need to run the BBB from 5V; it can happily run from a lower supply. This means that a single 3.7V cell could be used to power the entire board. No need to step-up to 5V or to run dual cells and step-down to 5V, both of which could have been inefficient.

The BBB has four holes that are suitable for connecting up the battery. They are detailed in the BBB system reference manual (SRM) enter image description here

Now I personally was able to power it up omitting the 10k resistor mentioned in lieu of a thermistor, where Batt+ goes to both TP5 & TP6, Batt- to TP8. The thermistor (or 10K resistor bypass) would have been between TP8 and TP7

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Would I need a step-up DC converter or something? And where on the BBB would I connect it?

From what I can tell the BBB needs 5V at a few hundred mA. You should be able to find a suitable boost (step-up) convertor from the likes of Linear Technology, Texas Instruments etc.. You'll probably even find ready made circuit boards that do this very job. Here's the power requirements specification: -

enter image description here

You'd connect it to the 5V supply connection point: -

enter image description here

Look top left hand corner of the picture above - it clearly says 5V.

Maybe think about using the LTC3529: -

enter image description here

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  • \$\begingroup\$ What type of cable do I need for that 5V pin? It looks like those bigger circular ones right? \$\endgroup\$ – JDS Feb 2 '14 at 21:01
  • \$\begingroup\$ @YoungMoney Sorry dude, I can't tell. I don't have a BBB so you're gonna have to do some research on line. Good luck. \$\endgroup\$ – Andy aka Feb 2 '14 at 21:42
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Yes. You can power up the BBB with a 3.7V (Single cell) Li-ion or Li-Po Battery. There are multiple options for powering up the BBB. First is through a mini-USB connector on-board (of course 5V), another is through 5V DC Adapter Jack and last is using Battery, which can be connected to TPx connectors given on the BBB adjacent to Power Management IC (PMIC). A few 5V pins on P9 header are directly connected to inputs from mini-USB and Adapter, which means that you can power up the BBB by giving the power through these pins directly, may be from some other board (be mindful that the BBB needs a few hundreds of milli-amperes of current to run smoothly, In my case, I have seen maximum current consumption close to 500 mA while heavily processing the data and media content)

TPx connectors adajacent to DC Jack

All the chips on the BBB operate on 3.3V or below. TI's TPS65217x PMIC takes the power input and distributes the power depending upon requirements throughout the Board. TPx pins given on the BBB are actually some of the designated pins on this PMIC. Whenever the BBB boots up, there is a whole set of configuration procedure which configures this PMIC for desired use. We can communicate with this chip using Linux commands like i2cget (PMIC is available to communicate at the address 0x24, status register of PMIC is at 0xA, try hitting command i2cget -y -f 0 0x24 0xA you will get some output depending upon the situation, go to TPS65217x datasheet and find out the meaning of the output you got by looking at the bits/representation of STATUS REGISTER in the datasheet). You can write scripts using such i2c commands to accomplish/automate a few tasks.

Kindly remember that, among TPx pins on Beaglebone, TP7 is for the temperature sensing of the battery connected between TP6 and TP8, +ve of the battery goes to TP6 and -ve goes to TP8. The designers of this system thought that you one choose a battery which comes with a protection circuit and a thermistor to limit the current while using, thermistors are special types of resistors in which the resistance varies depending upon the instantaneous value of the temperature, Since most of the Single Cell batteries in the market come without a NTC thermistor, you shall have to mimic it using a 10k resistor, so you should solder a 10k resistor across TP7 and TP8, as well short the TP5 and TP6 with a simple piece of wire or a zero ohm SMD resistor. So that PMIC "feels" that temperature is "okay". (Kindly note that PMIC TPS65217x can charge only a single cell battery which is generally operated in the range of 3.7V to 4.2V.

enter image description here

Single cell Li-ion/LiPo battery should be used only, its written so in the datasheet of TPS65217x, the default voltage it can charge the battery upto is 4.1V, you can change it by communicating with CHGCONFIG2 register of the PMIC using i2c commands, I suggest 4.2v is safe, since Single cell batteries are generally operated in this range, please refer to the ratings of the battery you are using, manufacturer specifies the operating limits)

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Actually - if you try the LiPo-battery out, there are several shortcomings, which limit the usability of it quite a lot. I have a BB-Black (ethernet) and a BB-Black-wireless. Tried it out on both:

It's documented, that when running on Battery, you have no 5V - and thus no USB ... But testing it in real-life - a lot of other effects show up:

BB-Black (ethernet):

  • you can boot fine, while on battery or 5V
  • Ethernet will work while on battery or 5V
  • of course - no USB - or other 5V gadgetry will work while on LiPo.
  • but generally - quite usable.

BB-Black-Wireless:

  • you can boot while on battery ... at least :-)
  • You will have NO WIFI and NO BT - in addition to NO USB.
  • There is no Wifi/BT - even if you re-plug the 5V.
  • Only a reboot while on 5V will bring back Wifi/BT

Suspend/Resume to mem: I've only tested this with a debian-9.3 image, and UART0 as wakeup.

(add no_console_suspend=1 to the kernel-cmdline)

Then in a shell:

echo enabled >/sys/devices/platform/ocp/44e09000.serial/tty/ttyS0/power/wakeup

echo 8 > /proc/sys/kernel/printk

echo mem >/sys/power/state

hit 'return' in the console (ttyS0) - and it should wake up - maybe...

On the BB-Black-Wireless, with the current kernel - I'm hitting a panic during the suspend (in the tilcd-driver) Won't even suspend. (seems like a known issue - so maybe there's a fix)

On the BB-Black (ethernet) - this works - with some limitations:

uname -r: 4.14.24-ti-r37 /etc/dogtag: rcn-ee.net console Debian Image 2018-03-09

  • Works fine, if you constantly power it via 5V. suspends/resumes fine.
  • Works fine, if you pull the 5V, suspend and resume while still on LiPo.
  • Works fine, if you pull the 5V, replug the 5V (no suspend)
  • FAILS (panic) if you pull the 5V - suspend while on LiPo - re-plug 5V!

The last case was, what I was initially interested in :-(

What kinda works:

  • boot (regardless whether on LiPo or 5V)
  • if the 5V goes away - continue running on LiPo. (no wifi/bt)
  • Have a script, which detects this - and do a clean shutdown.
  • like: i2cget -f -y 0 0x24 0xa - to check the status-reg of the pmic.
  • When you re-apply 5V - it will start up automatically.

quite enlightning - I seriously didn't expect it to be this limited.

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  • \$\begingroup\$ I have been checking the schematic of the BB-Black-wireless and I found that the D2 diode is not installed. Therefore, when the BB-Black-wireless works powered by battery the WiFi and bluetooth transceivers are not powered. I have installed a STPS1L30U diode (just because I have one in the lab) in the D2 footprint and I am testing the BB-Black-wireless. Now It is possible to boot while on battery and to have WIFI and BT. \$\endgroup\$ – rblasco Nov 7 '18 at 9:21

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