SmartFusion2/IGLOO2 devices need multiple power supplies for functional operation, programming, and high-speed serial interfaces. It is possible to design an application with only two voltage rails using SmartFusion2/IGLOO2 devices.
I/O banks in SmartFusion2 and IGLOO2 devices support a wide range of I/O standards. I/O bank supplies can operate at 1.2 V, 1.5 V, 1.8 V, 2.5 V, or 3.3 V. To obtain a two-voltage-rail design, the core voltage must be connected to 1.2 V, and the mandatory I/O bank supplies and VPP supplies can be connected to 2.5 V or 3.3 V.