8/3/2019 csave_add

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D0 D1 D2 D3

S0 S1 S3S2 S4

Co0

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A0 A1 C1 A2 B2 C2 A3 B3 C3B1B0 C0

RippleCarry Adder

CarrySaveStages

Addition of four 4Bit Numbers

Carry Save Adder (CSaA)

Note: Carry propagates diagonally through the array of adder cells

Worst case Delay for Addition of N numbers with mBit Resolution: Tpd = [N2+m]*tpd(FA)