All 3 are top institutions of india but the real fight of choosing is between nit trichy cse and iiit hyderabad ece if you are totally oriented towards cse then nit trichy is best go for it but if you can go with ece and want to innovate something then iiit hyderabad is good note that academic rigour is high in iiit hyderabad also placement wise nit trichy cse might be slight ahead so it depends on you and choose wisely.