Dear Joel, if you are talking about the Technical Entry scheme where in you are trained for 1 year and post that you study B.Tech for 4 years, then the minimum aggregate required is 70%. You need to complete your 10+2 with a minimum aggregate of 70% in Physics, Chemistry and Mathematics. It is the same across all Categories. There is no written examination. You need to clear the SSB exam post which you will have to undergo the Medical Exam. If you clear that, you will be hired to TES after which you can study B.Tech for 4 years