Dear Tommy,
Thanks for the reply. I am very sorry that there was some mistake in my schematic and after correcting the same I could be able to get the proper output. Sorry for the inconvenience.
Now I came across 2 new problems. They are explained below
1) My output voltage 12V is not stable upto 1A load current. It is swinging between 12.03V and 12.36V. Above 1A load current it is stable.
2) I am generating 12V output and the load current is 2A. When I increase the load current gradully from 0.1A to 2A in steps of 0.05A, the output is OK. But if I apply the load current of 2A suddenly, then the IC is drawing very excessive current and the output voltage drops down to 6.8V and increasing gradually further.
Please advise me a solution