What is the purpose of the TDA? Can you deposit promissory notes…

Greetings, I have been doing some research and if the corporations have the ability to to accept bills of exchange or promissory notes how are they cashing them? For instance I have 3 businesses and one of them I had a few folks send me promissory notes and bills of exchange. Would I deposit them into my business TDA account if so how? I did not see an option to be able to do so. When I look at the TDA it appears that you can purchase notes and then sell them.   I also can deposit them into my business bank account but then that is if the bank accepts them. What methodology are these corporations using to handle such debt instruments? Are they depositing all of those instruments into their TDA account?   Since Puerto Rico is no longer charging up the TDA then it would appear that an irrevocable trust is the next best route? Would it be safer just to create a trust account with the TDA? In other words when it asks you what type of TDA to open it asks you is your business a trust, a corporation, LLC, ETC.