iPhone keeps restarting at apple logo

''Hi there.

My iPhone 4S (model A1387) will not boot into iOS.

iPhone boots up initially and displays the apple logo for 3 seconds. Then it goes to a blank screen for another 3 seconds and the process repeats .

If charger disconnect it`s saying that it`s uncharged.

I changed the battery!

I tried a restore but I got the error No. 9 !

I tried to hold the home button and in the same time Sleep/Wake button , but same issue.

So anyone that can help me ?

I do not know if this is Hardware or Software issue....

Thanks,

hopefully someone will help me!''