AN 447: Interfacing FPGA Devices with 3.3/3.0/2.5 V LVTTL/LVCMOS I/O Systems - Provides guidelines for interfacing 3.3 V , 3.0 V , 2.5 V LVTTL or LVCMOS I/O systems with the Intel MAX 10 , Intel Cyclone 10 LP , Cyclone IV , and Cyclone III device families - 2022-03-28