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Altera_Forum's avatar
Altera_Forum
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13 years ago

MAX II CPLD output impedance

Hello all, We need to add an RC filter to certain outputs on our CPLD due to noise on our board, thus we need to know for impedance matching, what is the default output impedance for the M...
Altera_Forum's avatar
Altera_Forum
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13 years ago

Did you notice figure 5–1 output drive characteristics? It tells you everyhing about output impedance, just determine the slope in V/I characteristic.

I read about 30 ohm for 3.3V and low drive strength from the diagram.