The datasheet stated that the minimum operating voltage is 7V but my requirement is 5V.
Is there any chance that this IC can operate below 7V? What is the major blocking point that the IC can't operate below 7V?
The problem is that the part is not tested below 7V and it has not been characterized below 7V so there is no guarantee that it will work properly at 5V. There is an internal 5V regulator that will not be regulating but just passing through the incoming 5V but that probably would not be a problem.
In addition, the power output will be much less at 5V. So I strongly recommend you look into some of our other Class-D amps that have an analog input and is designed to operate at 5V.
Here is a link to the search of the selection tables.
Selection Table for Class-D Audio Amplifiers