If you plan to specialize in one particular branch related to your graduation branch, you can opt for it. Or, if you are currently working in some organization or have some work experience and there is a demand for a specialist in your organization, you can opt for it.

If you are not yet placed and still pursuing your B.Tech, I would suggest you first go for the placements and then give it a thought. NIT Trichy is a reputed institute and offers good academics. In fact, it is among the top NITs.