First, congratulations on completing a diploma in electronics and communication engineering and qualifying for the ECET exam. There are many good colleges you can choose in your rank; some of them are

1. Pragati Engineering College, Surampalem
2. Aditya Engineering College, Surampalem
3. GMR Institute of Technology, Rajam
4. Sri Vasavi Engineering College, Tadepalligudem
5. Vishnu Institute of Technology, Bhimavaram
6. Sree Vidyanikethan Engineering College, Tirupati

7. JNTU Kakinada (ECE)

I rank them according to your chances in these colleges so you can make your priority list.

All the best for future.