Low-power radix-4 combined division and square root

Because of the similarities in the algorithm it is quite common to implement division and square root in the same unit. The purpose of this work is to implement a low-power combined radix-4 division and square root floating-point double precision unit and to compare its performance and energy consumption with a radix-4 division only unit. Previous work has been done on reducing the energy dissipated in a divider. Here we apply the same techniques to the combined division and square root unit and consider modifications and tradeoffs. Results show that the energy dissipation for the combined division/square root unit can be reduced by about 35% without affecting the latency and an additional 20% reduction can be obtained using a dual voltage. Moreover the unit is 5% slower than a divider and its energy dissipation is 15% higher.