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An Effective Implementation of Dual Path Fused Floating-Point Add-Subtract Unit for Reconfigurable Architectures


Anitha Arumalla1*, Madhavi Latha Makkena2


1Velagapudi Ramakrishna Siddhartha Engineering College, Vijayawada, India
2Jawaharlal Nehru Technological University Hyderabad, Hyderabad, India


Reconfigurable architectures have provided a low cost, fast turnaround platform for the development and deployment of designs in communication and signal processing applications. The floating point operations are used in most of the signal processing applications that require high precision and good accuracy. In this paper, an effective implementation of Fused Floating-point Add-Subtract (FFAS) unit with a modification in dual path design is presented. To enhance the performance of FFAS unit for reconfigurable architectures, a dual path unit with a modification in close path design is proposed. The proposed design is targeted on a Xilinx Virtex-6 device and implemented on ML605 Evaluation board for single, double and double extended precision. When compared to discrete floating point adder design, the FFAS unit reduces area requirement and power dissipation as the later shares common logic. A Dual Path FFAS (DPFFAS) unit has reduced latency when compared with FFAS unit. The latency is further reduced with the proposed modified DPFFAS when compared with DPFFAS for reconfigurable architectures.


Discrete floating-point design, Dual path algorithm, Floating-point arithmetic, Fused floating-point operation, Leading zero anticipation.

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