A new type of optimal block distribution algorithm of two level carry-skip adder was described to determine optimal block distribution sizes. According to this algorithm, with the given total worst case delay, the maximum optimal block distribution sizes of the adder for that delay can be determined. It is simplified to obtain optimal block distribution of any desired adder sizes. The carry skip adder optimal block sizes can minimize critical path delay. The analysis of gate delay and complexity were provided. Although the two-level carry skip adder with optimal block distribution uses a few extra gates, it provides better speed than the adders with fixed size blocks. The adder has been functionally verified and simulated by using PSPICE. The simulation analysis of time delay reveals that the two-level optimal block distribution carry-skip adder can provide faster speed than the carry-skip adder with fixed size blokes.
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