why my ipad mini is keep restarting? please read this quick help!!!

my ipad mini wifi keeps restarting when i touch the screen or i play some games on it. it will fade to black suddenly, and then it will show the apple logo then and it will turn on then if will use it again it will does the same again.... I reboot it, reset to factory settings, and erase all the data,app,pic,music on it. but it keeps on happening. I'm frustrated. on my ipad mini why does this happend?? does this have an problem?? or virus? anything???
thanks apple please help me >.< I'm a Filipino so i'am difficult to speak in english please.