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Altera_Forum
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14 years ago

Design doesn't fit because of insufficient LAB

Hi all, I did a lot of redesign to reduce the register count and ALUT count. But it still doesn't fit because of lack of LAB. Could anyone tell me something about LAB? What is that used for? ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
14 years ago

LUT_RAM is a special capability of the LUT inside of an ALM having a feedback path that allows it to act like a FF instead of logic. It's not very useful, and not a good trade-off, but some designs that are extremely pipelined get some savings with it. They got rid of it for Stratix V and doubled the number of registers in the ALM.