Topic: Flashing screen after overvoltage

Hi guys, I have a Chumby One I was trying to turn into a robot brain. Some time ago I cut the power cord and added a keyed connector so I can plug it in a microcontroller board. While a friend was working on the software (ssh from a looong distance), Chumby was plugged into the wall and had a Arduino compatible board connected to the USB through a hub, together with a stick for storing the custom data. It worked fine plugged into the wall, but unfortunately I forgot about the input voltage limit and I plugged a 2S LiPo (7.4V) into the connector. Chumby did not start, so I thought I might had reverse polarity and immediately unplugged it.  I verified the polarity, it was fine. Only then I turned Chumby over and noticed the 5V marking near the power connector. Ugh... So I plugged the wallwart back and Chumby started, but the screen is flashing, same is the LED on the USB hub. The boot process gets stuck at finding the network, I guess the wireless dongle does not get enough power to work, or it might be damaged. Also, there is a part that gets really hot after a little while, I managed to identify it as U301. After a little longer, other parts near by get hot.

Can anyone let me know which parts might have gone bad and need replacing?

Thank you so much for your time and effort!


Re: Flashing screen after overvoltage

>Can anyone let me know which parts might have gone bad and need replacing?

The unit   smile

Re: Flashing screen after overvoltage

Thanks, that helps a lot tongue

Really, any educated guess? I would like to try and fix it if possible...

Re: Flashing screen after overvoltage

U301 is just one of several components that could easily be burned out by overvoltage.  Your CPU is also probably fried.  Some components that only are exposed to internally regulated supplies may still be okay, but frankly your best bet at this point is to buy another chumby.

Re: Flashing screen after overvoltage

The CPU, voltage regulators and probably several other components are fried. Better to buy a new.