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This paper proposes a technique for dynamic power reduction of pipelined processors. It is based on eliminating unnecessary transitions that are generated during the execution of NOP instructions. The approach includes the elimination of unnecessary changes in pipe register contents and the limitation of boundary movement of transitions caused by inevitable changes in pipe register contents due to insertion of a NOP into a pipelined processor. To assess its efficiency, the proposed technique is applied to MIPS, DLX, and PAYEH processors considering a number of benchmarks. The experimental results show that the techniques can lead to up to 10% reduction in the dynamic power consumption at a cost of negligible (almost zero) speed and (about 0.2%) area overheads. [ABSTRACT FROM AUTHOR]

Time, power, and data volume are among some of the most challenging issues for testing System-on-Chip (SoC) and have not been fully resolved, even if a scan-based technique is employed. A novel architecture, referred to the Selective Trigger Scan architecture, is introduced in this paper to address these issues. This architecture reduces switching activity in the circuit-under-test (CUT) and increases the clock frequency of the scanning process. An auxiliary chain is utilized in this architecture to avoid the large number of transitions to the CUT during the scan-in process, as well as enabling retention of the currently applied test vectors and applying only necessary changes to them. The auxiliary chain shifts in the difference between consecutive test vectors and only the required transitions (referred to as trigger data) are applied to the CUT. Power requirements are substantially reduced; moreover, DFT penalties are reduced because no additional multiplexer is utilized along the scan path. Data reformatting is applied in order to make the proposed architecture amenable to data compression, thus permitting a further reduction in test time. It also permits delay fault testing. Using ISCAS 85 and 89 benchmark circuits, the effectiveness of this architecture for improving SoC test measures (such as power, time, and data volume) is experimentally evaluated and confirmed. [ABSTRACT FROM AUTHOR]

In this paper, a 7T SRAM cell with differential write and single ended read operations working in the near-threshold region is proposed. The structure is based on modifying a recently proposed 5T cell which uses high and low V TH transistors to improve the read and write stability. To enhance the read static noise margin (RSNM) while keeping the high write margin and low write time, an extra access transistor is used and the threshold voltages of the SRAM transistors are appropriately set. In addition, to maintain the low leakage power of the cell and increase the I on / I off ratio of its access transistors, a high V TH transistor is used in the pull down path of the cell. To assess the efficacy of the proposed cell, its characteristics are compared with those of 5T, 6T, 8T, and 9T SRAM cells. The characteristics are obtained from HSPICE simulations using 20 nm, 16 nm, 14 nm, 10 nm, and 7 nm FinFET technologies assuming a supply voltage of 500 mV. The results reveal high write and read margins, the highest I on / I off ratio, a fast write, and ultra-low leakage power in the hold “0” state for the cell. Therefore, the suggested 7T cell may be considered as one of the better design choices for both high performance and low power applications. Also, the changes of cell parameters when the temperature rises from −40 °C to 100 °C are investigated. Finally, the write margin as well as the read and hold SNMs of the cell in the presence of the process variations are studied at two supply voltages of 400 mV and 500 mV. The study shows that the proposed cell meets the required cell sigma value (6 σ ) under all conditions. [ABSTRACT FROM AUTHOR]