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Altera_Forum's avatar
Altera_Forum
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15 years ago

Equivalent logic element of an ALUT?

Hi everyone,

Could anyone tell me the equivalent logic element of an ALUT?

From the catalog I know that an ALM is equivalent to 2.5 logic elements but can't find how many logic elements does an ALUT equate to

Thanks guys

Best regards,

Chris

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    One ALUT is essentially half an ALM. By being adaptive, it's not really black-and-white though. For example, if you have an ALUT that does a 6-input function, you might be able to pack something into the other side, but maybe not. It certainly makes size counting more difficult.

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    you'll really want to run Quartus and compile some designs to get an idea of resource usage and performance for your logic.

  • Altera_Forum's avatar
    Altera_Forum
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    15 years ago

    Thanks for all your replies.

    I ran some compilations for designs in Quartus II and wanted to see how the designs compared for different device families. The speed difference of the families were clearer, as in fmax and delays, but I can't really make much out of the size difference of a Stratix and Cyclone, as they use different logic architecture. Any way that I can compare the ALUT and Logic element in terms of size?

    Appreciate any replies.

    Best regards,

    Chris