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When RTL designers define the hierarchy of a system, they exploit their knowledge about the conceptual abstractions devised during the design and the functional interactions between the logical components. This valuable information is often lost during physical synthesis. This paper proposes HiDaP, a novel multi-level algorithm that uses RTL information and analytical methods for the macro placement problem of modern designs dominated by multi-cycle connection pipelines. By taking advantage of the hierarchy tree, the netlist is divided into blocks containing macros and standard cells, and their dataflow affinity is inferred considering the register latency and flow width of their interaction. The layout is represented using slicing structures and generated with a top-down algorithm capable of handling blocks with both hard and soft components. An adaptive multi-objective cost function is used to simultaneously minimize wirelength, timing, overlap and distance to preferred locations, which can be user-defined or generated by analytic methods (spectral and force-directed). These techniques have been applied to a set of large industrial circuits and compared against state-of-theart commercial and academic placers, and also to handcrafted floorplans generated by expert back-end engineers. The proposed approach outperforms previous algorithmic methods and can produce solutions with better wirelength and timing than the best handcrafted floorplans. Post-routing layouts are almost brought to timing closure and DRC cleanness with minimal engineer modification, showing that the generated floorplans provide an excellent starting point for the physical design flow and contribute to reduce turn-around time significantly. This work has been partially supported by a grant from Inphi Corporation and funds from the Spanish Ministry for Economy and Competitiveness and the European Union (FEDER funds) under grant TIN2017-86727-C2-1-R, and the Generalitat de Catalunya (2017 SGR 786).

Process-induced and environmental fluctuations play an important role in the design process for modern high-performance integrated circuits. The conventional principle of considering the verification of worst-case requirements reduces the performance that can potentially be achieved by circuits and technology. This paper presents a new mechanism that permits the compensation of random independent delay fluctuations due to environmental factors. It shows that it is significantly possible to reduce the latency time of a circuit even for a moderate length of pipeline stages.

In the paper, an analytical model for ground bounce noise evaluation taking into account the interdependence between IDD switching current and VDD noise voltage is presented. The model shows the discrepancies from general accepted assumption of independence between the two variables. The main conclusion is that noise calculations using the independence assumption cause an overestimation of the noise levels. The results are verified through realistic simulations and for different technology nodes and accurate analysis of two canonical circuits.

Shape memory alloys (SMA) are good candidates for solid state dampers because of their large recoverable strain and hysteresis. In this work, experimental analysis and modeling of the thermomechanical behavior for two SMAs is done. The SMA models are developed and included in a finite element simulation environment (ANSYS). Using these developing tools, a complete damping solution for a family house is outlined. The paper presents the design and optimization methodology for the dampers, analyzes their performance, and quantifies the relevant physical effects from the experimental measurements. The simulation results show that the SMA dampers are capable of reducing the maximum oscillation amplitude induced by “El Centro” accelerations by a factor 2 and that they dissipate 50% of the energy transmitted to the structure. Furthermore, SMA dampers constitute a passive, unsupervised damping solution appropriate for family houses.

The behavior of shape memory alloys (SMA) allows their use as a passive smart material. In particular, the existence of a hysteretic cycle in the domain of the elementary coordinates strain-stress-temperature (σ, E, T) suggests its application for damping in mechanical and/or in civil engineering. We are working in the application of SMA as dampers for earthquakes in small houses as family homes. For dampers installed in the inner porticos of the house, the suggested SMA is the CuAlBe and, eventually, the NiTi. At room temperature the used SMA wires induces forces situated between 2-3kN/wire. The properties related with the damping applications for CuAlBe and NiTi, i.e., the SMA creep and the self-heating will be presented, together with some other minor stress and temperature effects on NiTi modifying the hysteretic behavior.

An improved accuracy is researched in flat and silicon based nano-calorimeters related to fluid reaction via drop-to-drop 'reaction' or via a steady state in continuous injection of two reactants inside a working chamber. Two types of the experimental aspects of the sensitivity changes, related to 3-D effects, are described: drop effects and volume rate effects. To increase the accuracy, well-controlled joule measurements are dissipated in the manufacturer resistance and in several resistances in carefully controlled experiments. The shape factor (SF) values reduce the manufacturer's joule sensitivity up to fifty per cent. a working methodology is proposed: the results are compared with the standard TRIS reaction. The results suggest that the systematic error can be reduced to ±5%.

Efficient prediction of the substrate noise generated by large digital sections is currently a major challenge in System-on-a-Chip design. A macromodel to accurately and efficiently predict the substrate noise generated by digital standard cells is presented. The macromodel is generated from identification of the physical elements relevant to noise generation. Techniques to directly or indirectly compute the values of the elements in the cell macromodel are proposed. Using this macromodel, prediction of the noise generated by large digital sections can be easily done following a methodology based on high-level logic simulation. As a first step to validation, the macromodel accuracy is demonstrated in some circuits consisting of a reduced number of gates.

This paper presents a probabilistic approach to model the problem of power supply voltage fluctuations. Error probability calculations are shown for some 90-nm technology digital circuits. The analysis here considered gives the timing violation error probability as a new design quality factor in front of conventional techniques that assume the full perfection of the circuit. The evaluation of the error bound can be useful for new design paradigms where retry and self-recovering techniques are being applied to the design of high performance processors. The method here described allows to evaluate the performance of these techniques by means of calculating the expected error probability in terms of power supply distribution quality.

The particular properties of shape memory alloys (SMAs) are related to a martensitic transformation between metastable phases. Their applicability to dampers in civil engineering requires a fully guaranteed behaviour of the SMAs both on mesoscopic and atomic levels. The first one relates the thermomechanical properties (fracture, number of working cycles, summer-winter temperature effects and, for instance, self-heating associated with latent heat and the frictional work converted on heat) and the second one, the actions on the phase transition of the thermodynamic forces (temperature and stress). The properties of the CuAlBe alloy are explained and the characteristics of the NiTi alloy are outlined. By establishing an appropriate model the SMA dampers are introduced inside a structure and, via the ANSYS software, the dynamic response of the free and of the damped structure are obtained by simulation under the action of acceleration from the earthquakes available in the literatu re. As a conclusion, the conditions for the appropriateness of the dampers are given.