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Altera_Forum's avatar
Altera_Forum
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16 years ago

Question on LE

Dear all, Im wondering if it is possible to have a design that actually has fewer logic gates but took up more LE than another design that has more logic gates? This is happened to my desi...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
16 years ago

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Design A has 36AND 96XOR , consumed 82 LE, while

design B has 35AND 120XOR, consumed 79 LE

i think it will be odd to report a result as such in my work.

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LE elements your project requires are mostly related to HOW they are connected, not only to the number of logic gates you use in the design.

For example, a long AND/XOR chain could be synthesized in a few LE, if the resulting logic function can be simplified.

On the other hand, if a gate output must drive a lot of input gates, the compiler may replicate it on more than one LE to meet the high fan out requirement.