I'm looking for a chip which can play media files stored in a pen drive connected to it on LCD tv
A "chip" that does this with no other support is unlikely to be available. But, ...

There are a number of small, moderately low cost, self contained single-board or modular computers that do this with ease. One example is the $US25 "Raspberry Pi". This could meet your need with the Raspberry Pi itself, a programmed SD card, a 5V power supply (could be via USB cable or battery or other, and a video output cable.



Raspberry Pi:

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Larger than life photo (probably). Actual size is about the same as a credit card. (Photo from Wikipedia).





Element 14 purchase point - people have received RPs. 

RS purchase point - MAY be available

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