Video Lectures by D. B. V. Ravi Sankar

CLA:

Carry Look Ahead Adders are designed to overcome the latency introduced by the rippling effect of the carry bits. The CLA algorithm is based on two main terms ‘Generate’ and ‘Propagate’ terms. The name CLA is Justified because carry in value at each bit position is calculated ahead of addition.

CLA Part 2

High Speed Adders:

High Speed Adders are mainly designed to increase the computing speed of addition when compared to a ripple carry adder and carry look ahead adder.

Carry select adder mainly focuses on splitting the addition into two parts and examining the carry out generated from the first part.

Carry save adder mainly focuses on full adder logic. In full adder 3 inputs produces 2 outputs. The same concept has been extended in carry save adder in which any number of inputs will produce only 2 outputs.

Carry skip adder mainly focus on carry-skip logic in which the addition is performed in several blocks. Carry in bit at LSB can skip any one of the blocks before reaching MSB by examining the carry-skip logic value for each block.