A Dual Dielectric Approach for Performance Aware Reduction of Gate Leakage in Combinational Circuits

Design of systems in the low-end nanometer domain has introduced new dimensions in power consumption and dissipation in CMOS devices. With continued and aggressive scaling, using low thickness SiO2 for the transistor gates, gate leakage due to gate oxide direct tunneling current has emerged as the major component of leakage in the CMOS circuits. Therefore, providing a solution to the issue of gate oxide leakage has become one of the key concerns in achieving low power and high performance CMOS VLSI circuits. In this thesis, a new approach is proposed involving dual dielectric of dual thicknesses (DKDT) for the reducing both ON and OFF state gate leakage. It is claimed that the simultaneous utilization of SiON and SiO2 each with multiple thicknesses is a better approach for gate leakage reduction than the conventional usage of a single gate dielectric (SiO2), possibly with multiple thicknesses. An algorithm is developed for DKDT assignment that minimizes the overall leakage for a circuit without compromising with the performance. Extensive experiments were carried out on ISCAS'85 benchmarks using 45nm technology which showed that the proposed approach can reduce the leakage, as much as 98% (in an average 89.5%), without degrading the performance

Analytical Modeling and Reduction of Direct Tunneling Current during Behavioral Synthesis of Nanometer CMOS Circuits

Gate oxide direct tunneling current is the major component of static power dissipation of a CMOS circuit for low-end technology, where the gate dielectric (SiO 2 ) thickness is very low. This paper presents a novel direct tunneling current reduction method during behavioral synthesis of nanometer CMOS circuits. We provide analytical models to calculate the direct tunneling current and the propagation delay of behavioral level components. We then characterize those components for various gate oxide thicknesses. We also provide an algorithm for behavioral scheduling for minimizing the overall tunneling current dissipation of datapath circuits. The algorithm explores dual oxide thickness option for reducing direct tunneling current. We have carried out extensive experiments for various behavioral level benchmarks under various resource constraints and observed significant reductions in tunneling current

States of a SRAM Cell

The increasing market demand for ever smaller and application packed portable electronic devices has been fueling the relentless scaling of the CMOS transistor. The ITRS roadmap envisages that high performance CMOS circuits will require ultra-low gate oxide thickness to overcome the effects of shorter channel lengths. However, such devices will be susceptible to a more profound leakage mechanism due to carrier tunneling through the gate oxide. Consequently, the gate oxide tunneling current has emerged as the major component of the leakage power consumption of nanoscale CMOS devices. In the case of an important CMOS circuit like Static RAM (SRAM) there is a high probability for the leakage currents to be manifested with more prominence. SRAMs form a vital component of the CPU cache therefore there is a critical need for analysis, explanation, and characterization of the various tunneling mechanisms SRAMs. This paper explores the gate leakage current scenarios in the READ, WRITE and IDLE states of the SRAM which can make significant contribution to modeling and reduction of gate leakage in SRAM circuits.

Exotic madness in Caribbean literature: From marginalization to empowerment and indigenization

peer reviewedCaribbean literature is replete with migrant figures that are viewed when they go abroad as both exotic and mad, the apparent otherness of their behaviour or life choices being perceived in the west as evidence of some form of mental imbalance. Victims of what Graham Huggan has called “a particular mode of aesthetic perception”, these characters distinguish themselves by their cultural difference which might inspire initial fascination, yet results in most cases in exploitative commodification often followed by radical rejection. The iconic example of such an occurrence is of course Antoinette, aka Bertha Mason, in Jean Rhys’s Wide Sargasso Sea (1960), the white creole who ends up locked up in the attic of Thornfield Hall, dreams of setting fire to it and is thought to eventually do so before jumping to her death. The first part of this essay analyses similar stories of exoticization followed by marginalisation written by West Indian authors and examines to what extent their characters manage to subvert their so-called exoticism to take advantage of it and achieve empowerment, however ambiguous this might turn out to be -- as it is the case for Antoinette. The texts that I focus on are Dionne Brand’s “Blossom, Priestess of Oya, Goddess of Winds, Storms, and Waterfalls” (1988) and Jean Rhys’s “Let Them Call It Jazz” (1962), two short stories in which the writers give us access to the characters’ allegedly deranged minds and thereby contribute to turning their exotic status on its head. The second part of this essay focuses on an even more radical way of addressing the assumed mental difference of the migrant other through a reading of Caryl Phillips’s The Lost Child (2015), a novel which could be said to indigenize the figure of the mad exotic. This novel indeed concentrates on a deeply depressive English woman, who nevertheless bears an intriguing resemblance with the two Rhys protagonists mentioned above. I argue that by conflating the figure of the mad exotic migrant with that of the depressed and disturbed English native Phillips not only interrogates the process of exoticization of the migrant other but also generates a form of empathetic familiarization with otherness that undermines any attempt to establish divisive categories and is ultimately a source of empowerment for the characters and the readers