| 摘要 |
A logic module for an FPGA includes a LUT formed from an N-level tree of 2:1 multiplexers. Each of the N inputs to the LUT is connected to the select inputs of the multiplexers in one level of the tree. Each of the data inputs at the leaves of the tree is driven by a configuration memory cell that produces either a logic 0 or a logic 1. The output of the single multiplexer at the last level of the tree forms a Y output and is coupled to one input of an XOR gate and to the select input of a two-input carry multiplexer. The 0 input of the carry multiplexer is coupled to a G input. A CI input is coupled to the other input of the XOR gate and to the 1 input of the carry multiplexer.
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