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I'm sorry for yet another question about migrating between devices in the same family, but I've not been able to find an explicit answer to my question on the Forum.
In migrating between, say, an EP3C5 and EP3C25 it's clear that some I/O pins on the EP3C5 will be used as GND/VCCINT on the EP3C25. If I connect these pins to GND/VCCINT in my design and then populate the board with an EP3C5, then some I/O pins with a VCCIO of 3.3V will be connected to 1.2V (VCCINT). Is this OK? Isn't this an indeterminate logic level? Many CMOS devices don't like this kind of thing and may draw excessive current.Link Copied
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Bigger FPGA needs more power. Yeah, you can set to MAX in Current Strength.
Sean- Mark as New
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In Quartus II, you can select migration devices for your design, and it returns you the preferred connections for all selected devices.
I assume there should be compilation warnings if pins are set to inappropriate levels?- Mark as New
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Thank you. Your response made me take a closer look at the pin planner where I noticed something that had escaped me before. It directs me to connect these pins to VCCINT even when I compile for an EP3C5 device. It must therefore be OK to do so.

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