An 8-bit Radix-4 Non-Volatile Parallel Multiplier

The data movement between the processing and storage units has been one of the most critical issues in modern computer systems. The emerging Resistive Random Access Memory (RRAM) technology has drawn tremendous attention due to its non-volatile ability and the potential in computation application. These properties make them a perfect choice for application in modern computing systems. In this paper, an 8-bit radix-4 non-volatile parallel multiplier is proposed, with improved computational capabilities. The corresponding booth encoding scheme, read-out circuit, simplified Wallace tree, and Manchester carry chain are presented, which help to short the delay of the proposed multiplier. While the presence of RRAM save computational time and overall power as multiplicand is stored beforehand. The area of the proposed non-volatile multiplier is reduced with improved computing speed. The proposed multiplier has an area of 785.2 μm2 with Generic Processing Design Kit 45 nm process. The simulation results show that the proposed multiplier structure has a low computing power at 161.19 μW and a short delay of 0.83 ns with 1.2 V supply voltage. Comparative analyses are performed to demonstrate the effectiveness of the proposed multiplier design. Compared with conventional booth multipliers, the proposed multiplier structure reduces the energy and delay by more than 70% and 19%, respectively.

New Concept of Universal Binary Multiplication and Its Implementation on FPGA

This paper proposes the new improvements of signed binary multiplication equation, signed multiplier, and universal multiplier. The proposed multipliers have low complexity algorithms and are easy to implement into software and hardware. Both signed, and universal multipliers are embedded into FPGA by optimizing the use of LUTs (6-LUT and 5-LUT), carry chain Carry4, and fast carry logics: MUXCYs and XORCYs.Each one is implemented as a serial-parallel multiplier and parallel multiplier. The signed multiplier executes four types of multiplication, i.e., between two operands that each one can be a signed positive (SPN) or signed negative numbers (SNN). The universal multiplier can handle all (nine) types of multiplication, where each operand can be as unsigned(USN), signed positive, and signed negative numbers. For 8x8 bits, signed serial-parallel and signed parallel multipliers occupy19 LUTs and 58 LUTs with a logic time delay of 0.769 ns and 3.600 ns. Besides, for 8x8 bits, serial-parallel and parallel universal multipliers inhabit 21 LUTs and 60 LUTs with a logic time delay of 0.831ns and 3.677 ns, successively.

Design of Parity Preserving Reversible DIF-FFT using 90nm Technology

Reduction of power consumption is the major goal in modern circuit design. Reversible logic gate do not lose any information & thus have zero power dissipation. In all signal processing applications, the most important computation involved is Fast Fourier Transform (FFT). For the fault tolerance computation parity preserving logic can be used .The authors present an efficient parity preserving reversible DIF-FFT using 90nm technology. The implementation involves the design of DIF-FFT with reversible P2RG along with Fredkin gate over different combinations of adders (Carry look ahead adder (CLA), Carry save adders (CSA), Carry skip adder (CSK) & Ripple carry adder (RCA)) & multipliers (Array Multiplier (AM), Carry Save Multiplier (CM), Parallel Multiplier (PM), Wallace Tree Multiplier (WM)). DIF-FFT Architectures of different combinations were coded using Verilog & the same was simulated by Modelsim 6.3f. Parameters such as Hardware Device utilization & Power analysis were done using Quartus II 9.0 with respect to Stratix II device which works on 90nm technology. It was found that DIF-FFT Architecture designed using CSA & CM uses lesser resource utilization whereas architecture designed using CSA & AM has lesser Power dissipation by 72% & 81% respectively.