Innocent until proven guilty ...

... is not found anywhere in the U.S. Constitution.

Interesting. I did not know this.

Who invented the idea or where did it originate from ?

6th century Roman law apparently.

Wait, are you sure it isn't in part from the 5 th admendment?

Go look. I tried to find it. It's not in there.

Thats right , it is not in the constitution but

the 5Th , 6Th and 14Th amendment's created presumption of innocence ?

It's a principle that the legal system is shaped around. Much in the same way that the 1st Amendment does not use the phrase "separation of Church and State," it's more of a concept that the government tries to follow (sometimes better than others..)