An efficient design method for a 24 × 24 bit ＋48 bit parallel saturating multiply-accumulate （MAC） unit is described. The augend in the MAC is merged as a partial product into Wallace tree array. The optimized...An efficient design method for a 24 × 24 bit ＋48 bit parallel saturating multiply-accumulate （MAC） unit is described. The augend in the MAC is merged as a partial product into Wallace tree array. The optimized saturation detection logic is proposed. The 679. 2 μm × 132. 5μm area size has been achieved in 0. 18 μm 1.8 V 1P6M CMOS technology by the full-custom circuit layout design. The simulation results show that the design way has significantly less area （about 23.52% reduction） and less delay than those of the common saturating MAC based on standard cell library.展开更多
Using a strong nonlinear saturation absorption effect is one technique for breaking through the diffraction limit. In this technique, formation of a dynamic and reversible optical pinhole channel and transient superre...Using a strong nonlinear saturation absorption effect is one technique for breaking through the diffraction limit. In this technique, formation of a dynamic and reversible optical pinhole channel and transient superresolution is critical. In this work, a pump–probe transient detection and observation–experimental setup is constructed to explore the formation process directly. A Ge2Sb2Te5 thin film with strong nonlinear saturation absorption is investigated. The dynamic evolution of the optical pinhole channel is detected and imaged, and the transient superresolution spot is directly captured experimentally. Results verify that the superresolution effect originates from the generation of an optical pinhole channel and that the formation of the optical pinhole channel is dynamic and reversible. A good method is provided for direct detection and observation of the transient process of the superresolution effect of nonlinear thin films.展开更多
基金The National Natural Science Foundation of China(No.90407009),the National High Technology Research and Develop-ment Program of China(863Program) (No.2003AA1Z1340)
文摘An efficient design method for a 24 × 24 bit ＋48 bit parallel saturating multiply-accumulate （MAC） unit is described. The augend in the MAC is merged as a partial product into Wallace tree array. The optimized saturation detection logic is proposed. The 679. 2 μm × 132. 5μm area size has been achieved in 0. 18 μm 1.8 V 1P6M CMOS technology by the full-custom circuit layout design. The simulation results show that the design way has significantly less area （about 23.52% reduction） and less delay than those of the common saturating MAC based on standard cell library.
基金partially supported by National Natural Science Foundation of China (Nos. 51172253 and 61137002)
文摘Using a strong nonlinear saturation absorption effect is one technique for breaking through the diffraction limit. In this technique, formation of a dynamic and reversible optical pinhole channel and transient superresolution is critical. In this work, a pump–probe transient detection and observation–experimental setup is constructed to explore the formation process directly. A Ge2Sb2Te5 thin film with strong nonlinear saturation absorption is investigated. The dynamic evolution of the optical pinhole channel is detected and imaged, and the transient superresolution spot is directly captured experimentally. Results verify that the superresolution effect originates from the generation of an optical pinhole channel and that the formation of the optical pinhole channel is dynamic and reversible. A good method is provided for direct detection and observation of the transient process of the superresolution effect of nonlinear thin films.
