Welcome to our site! EDAboard.com is an international Electronic Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.
8 means speed 8Mhz
A means Thin (1.0 mm) Plastic Gull Wing Quad Flat Package (TQFP)
I means Industrial (-40°C to 85°C)
U means Pb-free packaging alternative (includes the industrial temperature range, too)
Either AU or AI for you means the same thing : 44-lead TQFP package working in temperature range (-40°C to 85°C)