White 32gb 3gs, Was out and plugged it into a portable power case for 20 mins, it was working while in it, 2 mins later pulled it out and it wasn't functional any more. I tried force restart (power + home) DFU mode and connecting it to itunes and it doesn't work. There appears to be no water damage. When plugging in it gets extremely hot and nothing shows up, just a black screen. Any help would be greatly appreciated.