I think you'll find that the TV money in England is divided equally amount each of the Premier League teams. Unlike in Spain where Barce & Madrid negotiate their own deals, meaning that these two teams account for the vast majority of TV money in spain, thus widening the gap further.
In England the Premier League is the place to be, nobody wants to watch Championship football, therefore it doesn't attract the same level of investment, naturally. I would say that if anything, clubs are becoming wise to the money issue and concentrating on developing younger players from the lower leagues and also the brand of football they play, look at Norwich & Swansea this season. A few years ago, teams like Bradford were paying Collymore and Benito Carbone £40k a week on 4 year deals, in an attempt to stay in the premier league, and look whats happened to them. Most of the teams who come up now are all sustainable such as Wolves, Stoke and West brom. Also, the parachute payments that teams recieve when they are relegated, is not replicated anywhere else in the world. So, from what i can see, if anything the gap between the Championship and the Premier League is probably closing, illustrated by the fact that more and more newly promoted teams are surviving their first seasons in the PL.