GST Registration in Same State

What if in case a person have one GSTin and same person starts a new business with different trade name .In such can he use same GSTIN of his old business or have to apply for new GSTIN ? 

Both businesses are of different type e.g. pharmaceuticals(name ABC) and the new one of clothes (name XYZ).

Yes, it is possible to take 36 registration in any state under the same PAN. Read this article to solve all your doubts about GST Registration https://irisgst.com/beginners-guide-to-online-gst-registration/ I hope I have solved your doubt.