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jAlter's avatar
jAlter
Icon for New Contributor rankNew Contributor
8 months ago

MAX 10. No 3.0 V Schmitt Trigger I/O standard

For some reason Max 10 doesn't support 3.0 V Schmitt Trigger I/O standard. Of course, using 3.3V I/O standard would work as well. But then Quartus would complain and would issue a fatal error if the...
Programmable Logic Device
FvM's avatar
FvM
Icon for Super Contributor rankSuper Contributor
8 months ago

Hi,
the missing link between above quoted datasheet table 8 (recommended Vi = -0.5 .. 3.6 V) and table 20 (Vih,max = Vccio + 0.3V) is the fact, that PCI clamp diodes are enabled in Quartus software for most IO standards by default.

You have to decide if your circuit involves possible input overshoot so that PCI clamp diodes must stay enabled to protect the FPGA or if they can be explicitely disabled.