OLIMEX© 2017
A20-OLinuXino-LIME2 user's manual
2.3 Powering the board
There are three possible ways of powering A20-OLinuXino-LIME2 – via external supply providing 5V
DC at the power jack, from 5V USB port via USB_OTG connector or from 3.7V Li-Po battery via the
LIPO_BAT. Note that the board might consume up to 650mA of current at 5V when there are no
peripherals connected to the USB hosts. Make sure your power supply is able to provide at least 1A
before. Depending on your preferred way of powering you might need additional hardware.
Important: Not all USB ports would be able to provide enough power for the board. Try using another
USB port/USB hub or a cable of higher quality.
If you have an LCD display connected to the board or external 2.5'' hard disk then the USB will NOT be
sufficient source of power.
The best practice is to never count on the mini USB-OTG as a single source of power for the board!
The preferred way of powering the board is via the PWR jack with 5V DC. This would make the board
fully powered and able to power all the peripherals connected to it.
Note that when powering the board from the USB_OTG, the current provided might be insufficient to
also power a bigger LCD connected to the LCD_con. However, this power option is capable of driving
the board when using external display connected to the HDMI connector.
The typical consumption of A20-OLinuXino-LIME2 is between 400mA and 650mA depending on the
current load.
If the board has entered power-down state you can bring it back without restart using the PWR_BUT. The
PWR_BUT is also used to start the board when powered from a Li-Po battery on the battery connector.
Sometimes when starting Android it is possible the board to enter battery save mode even before booting
fully. Especially, if you have turned off the board without quick boot mode enabled. In this case you
should press the PWR button for at least 5 seconds which would allow the board to start.
For the European customers we sell two power supply adapters, please check chapter 2.2. We also sell
USB OTG to USB type A cables if you lack such.
The default username/password combination for the default Linux image on the SD card (if purchased) is:
root/olimex.
Note that it is normal that when the board is powered some integrated circuits might appear hotter than
others. This is perfectly normal for some chips – for instance – voltage regulators and the main processor.
Page 11 of 51
