BiCMOS dynamic Manchester carry look ahead circuit for high speed arithmetic unit VLSI

A new BiCMOS dynamic Manchester carry look ahead circuit is presented, which is free from race problems, for VLSI implementation in a high speed arithmetic unit. Using the BiCMOS dynamic Manchester carry look ahead circuit, a 16 bit full adder test circuit which has been designed based on a 2 mu m BiCMOS technology, shows a more than two times improvement in speed as compared to the CMOS Manchester carry look ahead circuit. The speed advantage of the BiCMOS dynamic carry look ahead circuit is even greater in a 32 bit or 64 bit adder, which is very helpful for high speed VLSI CPU designs.