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Altera_Forum
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9 years ago

Cyclone III 3.3V LVTTL/LVCMOS input impedance

I have a customer that has an unusual driver arrangement for a couple Cyclone III 3.3V LVTTL/LVCMOS inputs and they want to know what the Cyclone III input impedance will be. Digging through the Alt...
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Altera_Forum
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9 years ago

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LVTTL/LVCMOS means high input impedance, the input pin impedance can be best modeled by a small capacitance of 5 - 6 pF, see datasheet table "Cyclone III Devices Pin Capacitance".

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Thanks FvM.

I am looking for a quantitative numeric value/range rather than a generic word description that can be interpreted multiple ways. While I do appreciate it can be modeled, the results are only as good as the input to the model and I would think that Altera can supply the needed details.

Regards.