OLIMEX© 2015
A10-OLinuXino-LIME user's manual
6.4 USB_OTG connector
The main way of changing the firmware image located on the NAND of A10-OLinuXino-LIME-
4GB is via the USB-OTG connector. How to change the firmware is explained after the hardware
details. The part of the schematic related to the USB_OTG is shown below:
The USB_OTG features Low Loss Power Distribution Switch SY6280 which protects the board in
case the devices you have plugged to the USB_OTG attempt to draw more current than 523mA
combined. The maximum current available on the 5V USB_OTG is exactly 523mA.
The SY6280 responsible for the USB_OTG is enabled by USB0-DRV (processor pin C12, port B9),
thus the USB_OTG is also controlled by the same signal.
Please note that the USB0-DRV (pin C12, port B9) is multiplexed with the I2S_DO1 signal! If you
are going to use the I2S audio interface then you would probably need to change the position of the
SMT jumper PB9/PH7_USB which by default connects USB_OTG to the PB9. This operation
would require cutting between the pads of the default position with a very sharp object and then
soldering the pads of the other position together. Doing so you would be able to use both the
USB_OTG (via port PH7 this time) and the I2S interface.
Additionally, PB9/PH7_GPIO jumper controls which of the two ports (PB9 or PH7) should be lead
out to pin 9 of GPIO3 connector for easier access. By default this jumper is in PH7_GPIO position
and PH7 is lead to pin 9 of GPIO3.
USB_OTG connector
Pin #
Signal name
Processor pin
1
+5V_OTG_PWR
-
2
UDM0
N20
3
UDP0
N21
4
USB0-IDDET
B5
5
GND
-
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