[beagleboard] USB full power option

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1

Yes I did. I also looked at the data sheet of the TPS65217 and it limits
the current from the USB connection to exactly 500mA. Anything over that
and it shuts down. So, we limited it to 500MHZ so that during the boot
process when it is banging on the SD card, the current will not exceed the
500mA and power down.

The USB socket can indeed just provide power, BUT, it cannot exceed 500mA
as I describe above.

GeraldYes I did. I also looked at the data sheet of the TPS65217 and it limits
the current from the USB connection to exactly 500mA. Anything over that
and it shuts down. So, we limited it to 500MHZ so that during the boot
process when it is banging on the SD card, the current will not exceed the
500mA and power down.

The USB socket can indeed just provide power, BUT, it cannot exceed 500mA
as I describe above.

Gerald

2

ok i think i am lost. from the tps65217 data sheet (slvsb64e):

• 100-mA, 500-mA, 1300-mA or 1800-mA Current Limit on USB Input

from page 43, power path control register:

USB input current limit
00 – 100 mA
IUSB[1:0] 01 – 500 mA
10 – 1300 mA
11 – 1800 mA

3

If you change the default SW then I suspect you can get it to 1800 although it has not been tested and the PCB layout was not done with that in mind.If you want to change the settings in the TPS65217 by changing the SW, use a power supply with a USB jack, and give it a shot, then go for it. However, if the current is higher than 500mA on boot, then you will not get the chance to change the setings unless you create a custom Uboot.

Gerald