Description
In an Active Serial (AS) configuration scheme for Cyclone III device, the VCCIO of I/O bank 1 must be 3.3V. In an Active Parallel (AP) configuration scheme for Cyclone III device, the VCCIO of banks 1, 6, 7 and 8 must be the same and must be either 1.8, 2.5, 3.0 or 3.3V.
Altera® recommends that you do not use level shifters between a configuration device and the Cyclone III device in any active (AS or AP) configuration scheme.