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fzliu's avatar
fzliu
Icon for New Contributor rankNew Contributor
6 years ago

MAX V: is it okay to leave VCCIO unconnected for unused I/O banks?

We're using the MAX V CPLD for our project (specifically, the 5M80ZM68). This CPLD has 2 I/O banks; one of them is unused in our application. From both a power and performance perspective, is it okay to leave VCCIO unconnected for that bank? Thanks!

1 Reply

  • YuanLi_S_Intel's avatar
    YuanLi_S_Intel
    Icon for Regular Contributor rankRegular Contributor
    6 years ago
    Hi Frank, It would be better if you have all the VCCIO connected to power rail. The reason is because MAX has power-on circuitry which will monitor the level of VCCIO during power up. Thus, it is important to have it connected so that the device can be power on successfully. Regards, YL