Is there any problem if a floating voltage exists on VCCH_GXB before it is ramped in Arria II, Arria V, Stratix IV, and Stratix V devices?

Description

No, there is no problem if a floating voltage exists on VCCH_GXB before it is ramped in Arria® II, Arria V, Stratix® IV and Stratix V devices. Leakage can occur between VCCT_GXB and VCCH_GXB which can cause VCCH_GXB to float to approximately 0.7V before the power supply is ramped up.  

This is expected behavior and will neither cause any functional failure nor reliability concern to the device.

This can only be observed if VCCT_GXB is powered up before VCCH_GXB and the regulators were designed to leave the power supplies to float before they ramp up.

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