The Early Power Estimator (EPE) version 9.0 SP2 (and later) and Quartus® II software PowerPlay Power Analyzer in version 9.0 SP2 (and later) show the minimum current requirements for each voltage supply used in a Stratix® IV device. For VCCIO, the minimum current requirement reported for ICCIO will be the same value for each voltage rail used in your design (1.2V, 1.5V, 1.8V, 2.5V, or 3.0V). Likewise, for VCCPD, the minimum current requirement reported for ICCPD will be the same value for each voltage rail used in your design (2.5V or 3.0V).
This value is based on all I/O pins in the device being powered by the same voltage rail, thus the minimum current requirement is repeated for each unique voltage rail used by VCCIO and VCCPD.
You can use the following equations to better estimate the minimum current requirements for ICCIO and ICCPD based on your device and design usage.
[(Number of I/O pins powered by VCCIO voltage) / (number of total I/O pins in the device)] * (Minimum supply current) * (1.10)
[(Number of I/O pins powered by VCCPD voltage) / (number of total I/O pins in the device)] * (Minimum supply current) * (1.10)
Repeat this formula for each VCCIO voltage and VCCPD voltage used in your design. The number of I/O pins powered by VCCIO / VCCPD voltage represents the count of both used and unused I/O pins in I/O banks powered by a particular voltage. The minimum supply current is the value provided in the power estimation tools for ICCIO and ICCPD.
The 1.10 scaling factor is provided as additional guardband and must be included for your power estimation.
You can use the Stratix IV Device Pin-Out Files to determine the I/O pin count for each I/O bank.