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 -

Page 24 of 45