Description:
This FAQ list down the requirement for VCCIO can be restored without device re-configuration.
Solution:
In the event the VCC and VCCIO0 have been affected by the power-down, all VCCIO will be in off-mode and thus it requires device re-configuration.
The user could retain the VCC and VCCIO0 to avoid re-configuration of the non-config VCCIO.
Refer to the following scenarios:
VCCIO0 (Bank 0): Configuration Bank Supply Voltage (store the configuration data)
A.
Refer to FPGA-TN-02055-2.5, Section 4. Configuration Process and Flow, VCCIO0 and VCC should be greater to 1.06V (Power-On-Reset ramp up trip point = MAX Voltage) else the power is not stable and will not proceed to the Initialization Phase.
B.
The VCCIO0 must remain within the Recommended Operating Conditions to ensure proper operation.
Other VCCIO: Non-Configuration Supply Voltage:
A.
Ramp-Down/Turn-Off will result in turning off its capability as I/O
B.
Ramp-Up/Turn-On will result in turning on its capability as I/O.
Without re-configuration as long as the VCC and VCCIO0 are intact with the configuration flow and POR.
In summary, the customer could power up/down other VCCIO except for the VCCIO0 to avoid re-configuration.
Please take note of the Power supply ramp rates for all power supplies. The details can be found in the datasheet: Power Supply Ramp Rates tables.