[marcello]

(19th Feb, 2015 08:34 AM)mansp Wrote:  

(19th Feb, 2015 01:23 AM)Exnor Wrote:  Is this data sheet usefull for you?

I did pick up a new micro usb cable today that was shorter, an old sony cable. It was perhaps half of the length of the old one that I have been using, and now the rainbow square is gone. So I guess that the cable was the weak link here. I am however stuck with my original problem, that the TV switches to the other hdmi source unless I plug the cable in that port.

Hi Mansp,
I got into quite some undervoltage issues too, and finally traced it back all the way to cheap micro USB cable's. I lost up to 0.25 volt for just the cable when feeding the more powerhungry Pi2, and usb stick and wifi.
5 Volts 2.4 amps is easily printed by 'less educated engineers' or their marketing buddies.
But providing a stable PSU for the Pi2 needs just a bit more than a cheap phone charger and cables you got lying around.
I have learned it the hard way too, and corrupted quite some SD setups in the process.
But Hey, I powered the pi2 ( and bplus ) from the TV and streamed heavy content which needed audio processing for output though the TV while it was rescanning the server library :-).
A 2 amps power supply that outputs just up to the max of 5.15 volt even at the rated max current does the trick for me, without changing the cables.
greetz M