Understanding the Potential and Limitations of Tunnel FETs for Low-Voltage Analog/Mixed-Signal Circuits

In this paper, the analog/mixed-signal performance is evaluated at device and circuit levels for a III-V nanowire tunnel field effect transistor (TFET) technology platform and compared against the predictive model for FinFETs at the 10-nm technology node. The advantages and limits of TFETs over their FinFET counterparts are discussed in detail, considering the main analog figures of merits, as well as the implementation of low-voltage track and-hold (T/H) and comparator circuits. It is found that the higher output resistance offered by TFET-based designs allows achieving significantly higher intrinsic voltage gain and higher maximum-oscillation frequency at low current levels. TFET-based T/H circuits have better accuracy and better hold performance by using the dummy switch solution for the mitigation of the charge injection. Among the comparator circuits, the TFET-based conventional dynamic architecture exhibits the best performance while keeping lower area occupation with respect to the more complex double-tail circuits. Moreover, it outperforms all the FinFET counterparts over a wide range of supply voltage when considering low values of the common-mode voltage

Corporate eco-efficiency and financial performance

Corporate social responsibility ("CSR" for short) is a form of corporate self-regulation integrated into a business model. CSR policy functions as a mechanism whereby business monitors and ensures its active compliance with the respect of the law, ethical standards, and international norms. The goal of CSR is to embrace responsibility for the company's actions and encourage a positive impact through its activities on the environment, consumers, employees, communities, stakeholders and all other members of the public sphere. In this paper the environmental aspect of CSR for the highest relevance in corporate governance and policy will be put in focus, and it can be synthesized in the “environmental social governance” concept. Particularly, a very interesting approach, analysed in this work, is concerning the link between CRS in environmental governance and corporate success, which could result in financial returns, in fair stock pricing, in a higher asset value, in efficient portfolio investment, in pricing firm equity, and so on – roughly speaking - in capital investment and in all financial and economic activity of the companies for satisfying shareholders. In order to establish the internal drivers of environmental performance, are usually selected a number of indicators that better reflect the characteristics of the enterprises and their environmental and financial performances, such as profitability, costs, size, energy consumption, efficiency, potential pollution and risk

Exploring the effectiveness of grey literature indicators and life cycle assessment in assessing circular economy at the micro level: a comparative analysis

PurposeMethods and tools to measure Circular Economy (CE) are in an early stage of development, especially on the micro level, and only limited guidance is available to companies’ decision-making processes related to CE solutions. In this context, the aim of this paper is to explore the suitability and effectiveness of grey literature CE indicators and the Life Cycle Assessment (LCA) method in measuring circularity at product or process level.MethodsThe analysis is based on two different comparative case-studies specifically related to the packaging sector, including glass and polyethylene terephthalate (PET) bottles, and to the food waste (FW) management sector, focusing on specific FW treatment activities. A review-of-reviews of CE metrics at the micro level is presented first in order to provide a theoretical overview on this specific theme and identify the available grey literature CE indicators and the role of LCA. Then, inventory data from both case studies are used as input to calculate LCA indicators as well as selected product-level grey literature CE indicators. Finally, the results are compared to critically analyze the potentiality in assessing circularity of these two streams of CE micro level assessment (LCA and CE indicators).Results and discussionThe main findings underscore that despite the common purpose of the selected CE indicators, the results related to the circularity performance may strongly vary depending on the evaluated case study and on the type of grey literature CE indicator that is applied. Regarding the application of the LCA method, the results highlight that, although a product may present high circularity performance, it does not necessarily carry lower environmental burdens. In addition, the LCA method allows obtaining useful information about both the environmental and circularity performance of the assessed case-studies.ConclusionsThe LCA method is presented as a suitable and effective method that businesses can apply to start a commitment towards CE. LCA can be considered the basic structured system on which to build a more complete metric framework for quantification of CE, specifically for companies that are aiming to operate more sustainably. On the contrary, grey literature CE indicators may not be always appropriate for assessing specific sectors or effectively contribute to assess environmental sustainability

Smart Material Implication Using Spin-Transfer Torque Magnetic Tunnel Junctions for Logic-in-Memory Computing

Smart material implication (SIMPLY) logic has been recently proposed for the design of energy-efficient Logic-in-Memory (LIM) architectures based on non-volatile resistive memory devices. The SIMPLY logic is enabled by adding a comparator to the conventional IMPLY scheme. This allows performing a preliminary READ operation and hence the SET operation only in the case it is actually required. This work explores the SIMPLY logic scheme using nanoscale spin-transfer torque magnetic tunnel junction (STT-MTJ) devices. The performance of the STT-MTJ based SIMPLY architecture is analyzed by varying the load resistor and applied voltages to implement both READ and SET operations, while also investigating the effect of temperature on circuit operation. Obtained results show an existing tradeoff between error rate and energy consumption, which can be effectively managed by properly setting the values of load resistor and applied voltages. In addition, our analysis proves that tracking the temperature dependence of the MTJ properties through a proportional to absolute temperature (PTAT) reference voltage at the input of the comparator is beneficial to mitigate the reliability degradation under temperature variations

STT-MTJ Based Smart Implication for Energy-Efficient Logic-in-Memory Computing

Spin-transfer torque magnetic tunnel junction (STT-MTJ) technology is an attractive solution for designing non-volatile Logic-in-Memory (LIM) architectures. This work explores a smart material implication (SIMPLY) LIM scheme based on nanoscale STT-MTJs. The SIMPLY architecture is benchmarked against the conventional material implication (IMPLY) logic. Obtained results prove that for similar performance the STT-MTJ based SIMPLY scheme ensures more reliable operation (i.e., lower error rate by more than three orders of magnitude) and an energy saving of -70% than its IMPLY counterpart, at the only cost of minimal area overhead

A Robust Sub-Threshold, Low Power-Delay, Energy and Area Efficient Level Shifter

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS681393-1397United State

A Robust, High-Speed and Energy-Efficient Ultralow-Voltage Level Shifter

10.1109/TCSII.2020.3033253IEEE Transactions on Circuits and Systems II: Express Briefs6841393 - 139

Short-interval leg movements during sleep entail greater cardiac activation than periodic leg movements during sleep in restless legs syndrome patients

Periodic leg movements during sleep (PLMS) are sequences of ≥4 motor events with intermovement intervals (IMI) of 10–90 s. PLMS are a supportive diagnostic criterion for restless legs syndrome (RLS) and entail cardiac activation, particularly when associated with arousal. RLS patients also over-express short-interval leg movements during sleep (SILMS), which have IMI <10 s and are organized mainly in sequences of two movements (doublets). We tested whether the cardiac activation associated with SILMS doublets differs from that associated with PLMS in a sample of 25 RLS patients. We analysed time–series of R–R intervals synchronized to the onset of SILMS doublets or PLMS that entailed an arousal during non-rapid eye movement (NREM) sleep. We assessed cardiac activation based on the R–R interval decrease with respect to baseline during NREM sleep without leg movements. We found that the duration of the R–R interval decrease with SILMS doublets was significantly longer than that with PLMS, whereas the maximal decrease in R–R interval was similar. Scoring SILMS in RLS patients may therefore be relevant from a cardiac autonomic perspective