what's the difference between SN74LVC2T45 and TXB0102 using in 3.3-V to 5-V Translation

In the simplest terms,  the LVC2T245 required the use of a direction pin. The TXB will automatically sense the signal direction. These contain different circuits and will behave differently under certain conditions.

The TXB devices have an applications note you can refer to for more information on this type of translator.

http://focus.ti.com/analog/docs/litabsmultiplefilelist.tsp?literatureNumber=scea043&docCategoryId=1&familyId=707