LCD power 5V 1.5-2A

[shug]

Hi all,
I would like to connect my Olinuxino A20 to the Chalk Elec 10" touchscreen
(http://www.chalk-elec.com/?page_id=1280#!/10-universal-LCD-with-HDMI-interface-and-capacitive-multi-touch/p/42545413/category=3094861).
This screen needs a power input of 5V 2A max (1.5A should be enough with backlight set to 100%)
I power my board with POE through the POE module V2 from Olimex (48V -> 12V)
I have a battery connected to the board
Now if i would like to power my lcd with the POE output I need a step-down circuit to fall from 12v (POE module output) to 5V (lcd input), right ? But If the main power fails (POE Switch or cable problem), the board will switch to battery mode but not the lcd.

So is there a way to power the lcd through the board ? with the USB connector ? SATA ? GPIO ?
I'm wondering if those methods can give enough current (1.5A)

Thanks
xavier

[JohnS]

I don't see the board providing anything like so much.

John

[dave-at-axon]

The 5V regulator on the A20 can't provide that current to external devices. You will need an external supply but you can switch this on and off from the 3.3V power from the A20. The 5V is always present so you can't use that.