TUSDB- Binance Chain
TUSDB is built on Binance Chain, a separate blockchain, and is a BEP-2 token, while TUSD is built on the Ethereum blockchain and is an ERC-20 token. They serve the same functionality - digital versions of U.S. Dollars that are backed 1:1 by a physical U.S. Dollar held in an escrow account. The primary difference is that they are built to be compatible with their respective blockchains.