BeagleBone Black Current Consumption

GoogleGroups
1

Hello,

I need to know how much current does the beaglebone black need in two situations:

  • worst case scenario - where everything is used (except extension headers)
  • specific setup - where i use the usb for wifi , data cable plugged in and debuger at once.

The data sheet says 1A is sufficient for powering the board but if i have power hungry devices like the wifi more may be needed.

Regards,
Cristian

2

Cristian,

There is a table of power consumption conditions in the TRM for the Beaglebone black. 460 ish mA when everything like USB / ethernet / hdmi etc is used( if memory serves ) But do double check, as my memory for such things isnt always perfect.

3

Oh yes i have seen that part, i wasn’t sure beacuse it said TBD in the table but now i see that that is only for the reset state only. And from what i understand the USB’s are limited to 500mA, and the kernel booting peak is 460mA. But it doesn’t specify for the other devices.

4

Ok now i see it specifies above the cnditions in which the test was done with practically everything connected. The only thing i need to know now is by how much the currentconcumtion rises while using wifi. Probably a litle bit over 500mA.

5

Ok now i see it specifies above the cnditions in which the test was done with practically everything connected. The only thing i need to know now is by how much the currentconcumtion rises while using wifi. Probably a litle bit over 500mA.

http://www.hardkernel.com/main/products/prdt_info.php?g_code=G137361754360

If you don’t have a way to measure the current consumption, this device might be handy.

6

Hello John,

I have looked at the link you have sent and it is a good idea but i can just hook up a multimeter and see the current consumption that way since i don’t have time to wait for the device to come.

Anyway as a slightly different question: I have been looking into the datasheet of the BBB and it says i can power the board thorugh the expansion header but doesn’t specify much else about that and the internet isn’t too clear on some details. So what i want to know is the following:

  • Are the pins i am supposed to power the beaglebone through pin 5 and 6 on P9? ( i am asking this beacuse when i powered the board through the barrel connector those pins outputted 5V ).

  • Is there a limit to how much power can be drawn through those pins, or does it draw however much the BBB needs ( i am estimating that with wifi and everything else it can get up to 600-700mA). The reference manual states that those pins can dish out 1A for supplying any add-ons, is it the same for when you supply power to them. On the board i am making the 5V voltage regulator that supplies the BBB can handle 2A so i am covered on that end.

7

PS (forgot about this one)

If i am powering the BBB through those pins and and i also plug in the usb to connect to the PC is there a problem?, is the power switched to the USB or does it remain on the pins like in the case where the USB and 5V Barrel are both connected?

8

PS (forgot about this one)

If i am powering the BBB through those pins and and i also plug in the usb to connect to the PC is there a problem?, is the power switched to the USB or does it remain on the pins like in the case where the USB and 5V Barrel are both connected?

Read the BBB SRM Section 6.1.4.

Regards,
John

9

Hello John,

I have looked at the link you have sent and it is a good idea but i can just hook up a multimeter and see the current consumption that way since i don’t have time to wait for the device to come.

You were asking questions about current consumption so I assumed you didn’t have any way to measure the BBB current requirements. Also see BBB SRM Section 6.1.7.

Anyway as a slightly different question: I have been looking into the datasheet of the BBB and it says i can power the board thorugh the expansion header but doesn’t specify much else about that and the internet isn’t too clear on some details. So what i want to know is the following:

  • Are the pins i am supposed to power the beaglebone through pin 5 and 6 on P9? ( i am asking this beacuse when i powered the board through the barrel connector those pins outputted 5V ).

This is the purpose of these pins. These pins are directly connected to the barrel connector.

  • Is there a limit to how much power can be drawn through those pins, or does it draw however much the BBB needs ( i am estimating that with wifi and everything else it can get up to 600-700mA). The reference manual states that those pins can dish out 1A for supplying any add-ons, is it the same for when you supply power to them. On the board i am making the 5V voltage regulator that supplies the BBB can handle 2A so i am covered on that end.

Going back to BBB SRM Section 6.1.7, the BBB these are the typical current requirements for the board. However, if you add capes, this current will increase, but is limited by the settings in the TPS65217C PMIC (see datasheet page 9 and page 43). Currently, the BBB current limit is set at 1,300mA which is set in the u-boot environment or uEnt.txt file.

If you use a regulator on your board to power the BBB, that is fine; however, if you use a regulator on your board to power your circuitry, make sure you only enable that regulator with the 3V3B voltage rail. Pay attention to the BBB SRM Section 7.1.2 (red warning). Also see BBB SRM Section 8.6.1.

Regards,
John