| 摘要 |
PURPOSE: A high speed and low power 4-2 compressor is provided to supply a high-speed and a low-power 4-2 compressor by decreasing a load capacitance loaded in the 4-2 compressor and decreasing an area occupied by the 4-2 compressor and an electric consumption therein. CONSTITUTION: The first logic circuit(110) responds to the first and second input data(I1,I2) being inputted from an exterior and outputs a NAND/NOR calculation result and an XOR/XNOR calculation result with respect to the data(I1,I2), respectively, and generates an output carry to the next terminal using the NAND/NOR calculation result. The second logic circuit(120) responds to the third and fourth data(I3,I4) being inputted from an exterior and a NAND/NOR calculation result being output from the first logic circuit(110) and generates a selection signal. The third logic circuit(130) responds to the selection signal being output from the second logic circuit(120) and generates one out of an input carry being inputted at a front-end and an inversion input carry into a sum. The fourth logic circuit(140) responds to the selection signal being output from the second logic circuit(120), selects one out of an inversion input carry being inputted at a front-end and an inverse fourth input data, and generates a carry.
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