How does the I.Sound AV Cable for iPod And iPhone charge your ipod while using it?

So I downloaded a television series from itunes. completely forgetting apple uses the m4v extension (and no its not an mp4 with apple's screwy m4v type) if it was i could just change the extension to mpg4 or avi and it would play in any media player and it does not work. i wanted to burn it to a dvd and play it on the dvd player but i have a sneaky suspicion it wouldn't play on the dvd player. someone suggested i use tunebite7 but i can't convert the mp4 file without buying their 50 dollar upgrade. so then i stumbled across in my ipod's video settings and there is a tv out setting which opened up a new possibility. i was going to try plugging in an av to headphone jack to see if that would work but i was like the headphone port is solely an audio out if if i connected it to the tv it wouldn't play, then apparently there is a chip or something that is only found in apple branded merchandise that would make signals clear/transmissible, this chip is not found in regular products so a regular product wouldn't work. I finally stumbled across the I.Sound AV Cable for iPod And iPhone which seems like it may work, but how does it charge my ipod? i wouldn't worry but i doubt my ipod battery will last long enough to make it through a 45 minute episode.