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Altera_Forum
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15 years ago

DCLK and DATA0 connected to LVDS output instead of floating

The Cyclone II handbook says that after programming, the DCLK and DATA0 inputs should not be left floating and should therefore be connected to a logic high or low. However, it also states that th...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

I'm not sure whether the external LVDS chips will be stronger, and as you are using the smallest EP2C devices you may as well give it a try.

To reduce the chance of breaking things you have to add additional protection devices as well.

Also you must protect the circuit from false cureent supply loops while hotplugging the system (this if you are using RJ45 connectors, or in fact almost any connector).

Did you think about the termination of the mixed LVDS-LVCMOS pair? You may run into an incompatibility there.