Multi Domino Double Manchester Carry Chain Adders for High Speed Circuits

The carry look-ahead adders are designed till now by using standard 4 bit Manchester carry chain. Due to its limited carry chain length, the carries of the adders are computed using 4 bit carry chain. This leads to slow down the operation. A high speed 8 bit (MCC) adder in multi output domino CMOS logic is designed in this work. Due to its limited carry chain length this high speed MCC uses 2 separate 4-bit MCC. The 2 MCC namely odd carry chain and even carry chain are computed in parallel to increase the speed of the operation. This technique has been applied for the design of 8 bit adders in multi output domino logic and the simulation results are verified. Results prove that 8bit MCC produces less delay compared to conventional 4 bit delay. The reduced delay realizes better speed compared to the conventional designs. The existing design and the previous designs are designed and simulated using TANNER EDA.