2.5VCCIO and 1.8V logic

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If I have VCCIO connected to 2.5V (which is required for LVDS), can the same IO bank accept 1.8V logic?

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It could work but you have to keep a few things in mind:

- Like Ironmoose wrote: be aware that the output will be 2.5V

- The minimum Vih of a 2.5V bank is 1.7V

- The Voh of your external device will be close to 1.8V in practice, but your datasheet will probably specify 0.7*Vcc or so. So not enough

- A pull-up resistor to 2.5V on the input signals could give these a last step.

- The noise margin (difference between Voh and Vih) will be very small

- The use of a schmitt trigger input will improve the noise insensitivity

Good luck, Ton

PS Maybe the bus hold functionality could be use, but I don't have any experience with it