I have a design using EP4CE15F23C9L which has 1.2 V connected to VCCINT (core voltage) instead of 1.0 V. This design is in production and has been operational for almost 10 years. I am wondering what kind of problems/effects this will have.

[JDWYE1]

I believe this would have positve effects on setup timing but not sure how much - I am currently rewriting some functionality for this and setup timing is violated according to TimeQuest.

[Rahul_S_Intel1]

Hi ,

From the datasheet of Cyclone 4 ,the maximum voltage for Vccint maximum voltage is 1.8V. page no:2 of the datasheet

https://www.intel.com/content/dam/www/programmable/us/en/pdfs/literature/hb/cyclone-iv/cyiv-53001.pdf

So may be that is the reason for the device is not going bad,

setup timing is violated according to TimeQuest

What is the violation