Because of the exceptional physical, chemical, electric and mechanical properties of hard and brittle materials, such as ceramics, glass and diamond film etc, those are considerably valued in high technology industry. Although those materials can be machined using the ECDM method, but mostly used for machining hole and wire cutting, there is few application in the polishing aspect. In this study, a high-precision dynamic electrical pitting tester is employed, the electrolyte is KOH(eq), investigate the behavior of static electrochemical discharge of supply voltage and electrolyte highly to the steel ball/glass, and analysis it¡¦s machining characteristic. From the experimental results, which are SEM pictures of machined glass and variations of current and force , we can clearly infer the electrochemical discharge machining mold, and establish electrochemical I-V curve under different electrolyte highly, and furthermore machining area classify for (1) non-machining district (2) precision machining district (3) middle machining district (4) heavy machining district. The experimental results shows, the pitting of damage width and depth and supply voltage are relation in direct ratio. Under three different electrolytes highly, shows the critical voltage of pitting damage are all the same value, namely 29V, and electrolyte highly will be influenced real machining time and damaged form of surface. In the precision machining district, can get the surface roughness (Ra) reach 0.02£gm, machining depth of surface damage reach 0.3649£gm after machined for 60 seconds under the optimum operating parameter.

The power consumption of Static Random Access Memory (SRAM) has become an important issue for modern integrated circuit design, considering the fact that they occupy large area and consume significant portion of power consumption in modern nanometer chips. SRAM operating in low power supply voltages has become an effective approach in reducing power consumption. Therefore, it is essential to experimentally characterize the single event effects (SEE) of hardened and unhardened SRAM cells to determine their appropriate applications, especially when a low supply voltage is preferred. In this thesis, a SRAM test chip was designed and fabricated with four cell arrays sharing the same peripheral circuits, including two types of unhardened cells (standard 6T and sub-threshold 10T) and two types of hardened cells (Quatro and DICE). The systems for functional and radiation tests were built up with power supply voltages that ranged from near threshold 0.4 V to normal supply 1 V. The test chip was irradiated with alpha particles and heavy ions with various linear energy transfers (LETs) at different core supply voltages, ranging from 1 V to 0.4 V. Experimental results of the alpha test and heavy ion test were consistent with the results of the simulation. The cross sections of 6T and 10T cells present much more significant sensitivities than Quatro and DICE cells for all tested supply voltages and LET. The 10T cell demonstrates a more optimal radiation performance than the 6T cell when LET is small (0.44 MeV·cm2/mg), yet no significant advantage is evident when LET is larger than this. In regards to the Quatro and DICE cells, one does not consistently show superior performance over the other in terms of soft error rates (SERs). Multi-bit upsets (MBUs) occupy a larger portion of total SEUs in DICE cell when relatively larger LET and smaller supply voltage are applied. It explains the loss in radiation tolerance competition with Quatro cell when LET is bigger than 9.1 MeV·cm2/mg and supply voltage is smaller than 0.6 V. In addition, the analysis of test results also demonstrated that the error amount distributions follow a Poisson distribution very well for each type of cell array.

Algumas técnicas foram criadas com o objetivo de reduzir o consumo de potência, dentre elas o uso de Mútiplas Tensões de Alimentação ajustadas de Forma Dinâmica(Multiple Dynamic Supply Voltage - MDSV). Essa técnica visa reduzir o consumo dinâmico utilizando pelo menos três tensões de alimentação diferentes dentro do chip. Para isso, é necessário que circuitos especiais de proteção sejam adicionados ao chip. Os conversores de tensão tem como objetivo aumentar ou diminuir o nível de tensão do sinal de entrada. O custo de introduzir os conversores de tensão, em circuitos que utilizam a técnica MDSV, é alto. Uma vez que isso causa aumento da área total e altera a temporização do chip. Com base nisso, esse trabalho propõem adicionar um caminho alternativo para a corrente, desviando e desligando os conversores de tensão enquanto eles não são necessários. Cabe salientar que alguns conversores de tensão ficam sem utilidade por causa da característica dinâmica dos circuitos contruídos usando MDSV. Com isso, neste trabalho é proposta uma nova construção para os conversores de tensão utilizados em conjunto com o MDSV. Nas simulações elétricas, os circuitos contendo essa nova construção apresentaram redução no tempo de propagação de até 13%, em comparação aos circuitos tradicionalmente utilizados para conversão de tensão. Além da redução no tempo de atraso, foram alcançadas reduções no consumo de potência na ordem de 14%. / Some techniques have been created with the purpose of reducing power consumption, among them the Multiple Dynamic Supply Voltage (MDSV). This technique aims to reduce the dynamic consumption using at least three different supply voltages inside the chip. Therefore, it is necessary that special protection circuits to be added to the chip. Level shifter aims to increase or decrease the voltage level of the input signal. The cost of introducing the voltage converters in circuits using the MDSV technique is high. As this causes increased total area and changes the timing of the chip. Based on this, this paper proposes to add an alternate path for current, deflecting off and the voltage converters as they are not required. It should be noted that some voltage converters are useless because of the dynamic characteristic of contruidos circuits using MDSV. Thus, this work proposes a new construction for the voltage converters used in conjunction with MDSV. In electric simulations, the circuit containing this new construction decreased to 13% in the propagation time in comparison to the circuits traditionally used for voltage conversion. In addition to reducing the delay time, reductions were achieved in the power consumption on the order of 14%.

Algumas técnicas foram criadas com o objetivo de reduzir o consumo de potência, dentre elas o uso de Mútiplas Tensões de Alimentação ajustadas de Forma Dinâmica(Multiple Dynamic Supply Voltage - MDSV). Essa técnica visa reduzir o consumo dinâmico utilizando pelo menos três tensões de alimentação diferentes dentro do chip. Para isso, é necessário que circuitos especiais de proteção sejam adicionados ao chip. Os conversores de tensão tem como objetivo aumentar ou diminuir o nível de tensão do sinal de entrada. O custo de introduzir os conversores de tensão, em circuitos que utilizam a técnica MDSV, é alto. Uma vez que isso causa aumento da área total e altera a temporização do chip. Com base nisso, esse trabalho propõem adicionar um caminho alternativo para a corrente, desviando e desligando os conversores de tensão enquanto eles não são necessários. Cabe salientar que alguns conversores de tensão ficam sem utilidade por causa da característica dinâmica dos circuitos contruídos usando MDSV. Com isso, neste trabalho é proposta uma nova construção para os conversores de tensão utilizados em conjunto com o MDSV. Nas simulações elétricas, os circuitos contendo essa nova construção apresentaram redução no tempo de propagação de até 13%, em comparação aos circuitos tradicionalmente utilizados para conversão de tensão. Além da redução no tempo de atraso, foram alcançadas reduções no consumo de potência na ordem de 14%. / Some techniques have been created with the purpose of reducing power consumption, among them the Multiple Dynamic Supply Voltage (MDSV). This technique aims to reduce the dynamic consumption using at least three different supply voltages inside the chip. Therefore, it is necessary that special protection circuits to be added to the chip. Level shifter aims to increase or decrease the voltage level of the input signal. The cost of introducing the voltage converters in circuits using the MDSV technique is high. As this causes increased total area and changes the timing of the chip. Based on this, this paper proposes to add an alternate path for current, deflecting off and the voltage converters as they are not required. It should be noted that some voltage converters are useless because of the dynamic characteristic of contruidos circuits using MDSV. Thus, this work proposes a new construction for the voltage converters used in conjunction with MDSV. In electric simulations, the circuit containing this new construction decreased to 13% in the propagation time in comparison to the circuits traditionally used for voltage conversion. In addition to reducing the delay time, reductions were achieved in the power consumption on the order of 14%.

Algumas técnicas foram criadas com o objetivo de reduzir o consumo de potência, dentre elas o uso de Mútiplas Tensões de Alimentação ajustadas de Forma Dinâmica(Multiple Dynamic Supply Voltage - MDSV). Essa técnica visa reduzir o consumo dinâmico utilizando pelo menos três tensões de alimentação diferentes dentro do chip. Para isso, é necessário que circuitos especiais de proteção sejam adicionados ao chip. Os conversores de tensão tem como objetivo aumentar ou diminuir o nível de tensão do sinal de entrada. O custo de introduzir os conversores de tensão, em circuitos que utilizam a técnica MDSV, é alto. Uma vez que isso causa aumento da área total e altera a temporização do chip. Com base nisso, esse trabalho propõem adicionar um caminho alternativo para a corrente, desviando e desligando os conversores de tensão enquanto eles não são necessários. Cabe salientar que alguns conversores de tensão ficam sem utilidade por causa da característica dinâmica dos circuitos contruídos usando MDSV. Com isso, neste trabalho é proposta uma nova construção para os conversores de tensão utilizados em conjunto com o MDSV. Nas simulações elétricas, os circuitos contendo essa nova construção apresentaram redução no tempo de propagação de até 13%, em comparação aos circuitos tradicionalmente utilizados para conversão de tensão. Além da redução no tempo de atraso, foram alcançadas reduções no consumo de potência na ordem de 14%. / Some techniques have been created with the purpose of reducing power consumption, among them the Multiple Dynamic Supply Voltage (MDSV). This technique aims to reduce the dynamic consumption using at least three different supply voltages inside the chip. Therefore, it is necessary that special protection circuits to be added to the chip. Level shifter aims to increase or decrease the voltage level of the input signal. The cost of introducing the voltage converters in circuits using the MDSV technique is high. As this causes increased total area and changes the timing of the chip. Based on this, this paper proposes to add an alternate path for current, deflecting off and the voltage converters as they are not required. It should be noted that some voltage converters are useless because of the dynamic characteristic of contruidos circuits using MDSV. Thus, this work proposes a new construction for the voltage converters used in conjunction with MDSV. In electric simulations, the circuit containing this new construction decreased to 13% in the propagation time in comparison to the circuits traditionally used for voltage conversion. In addition to reducing the delay time, reductions were achieved in the power consumption on the order of 14%.

Os Sistemas Digitais de Múltiplas Tensões exploram o conceito de dimensionamento da tensão de alimentação através da aplicação de diferentes fontes para regiões específicas do chip. Cada uma destas regiões pertence a um domínio de energia e pode ter duas ou mais configurações de voltagens. Independentemente dos distintos níveis de energia em diferentes domínios de tensão, os blocos devem processar sinais com níveis lógicos coerentes. Nestes sistemas, os Conversores de Nível (LS do inglês Level Shifters) são componentes essenciais que atuam como interfaces de escalonamento da tensão entre domínios de energia, garantindo a correta transmissão dos sinais. Com a apropriada interface de escalonamento de tensão e sua correta implementação, pode-se evitar o consumo excessivo de potência dinâmica e estática. Portanto, a concepção e implementação de conversores de nível deve ser um processo consciente que garanta o menor sobrecusto no tamanho, consumo de energia, e tempo de atraso. Neste trabalho estudam-se as principais características das interfaces de escalonamento de tensão e se introduce um conversor de tensão com eficiência energética e área reduzida, adequado para a conversão de baixo a alto nível. Apresentam-se os conversores de nível com o melhor desempenho encontrados na literatura, os quais são categorizados em dois principais grupos: Dois trilhos (Dual-rail) e Único trilho (Single-rail), de acordo ao número de linhas de alimentação necessárias. O circuito proposto foi comparado com a topologia tradicional de cada grupo, o Differential Cascode Voltage Switch (DCVS) e o conversor de Puri respectivamente. Simulações na tecnologia CMOS 130nm da IBMTM mostram que a topologia proposta requer até 93,79% menos energia em determinadas condições. Esta apresentou 88,03% menor atraso e uma redução de 39,6% no Produto Potência-Atraso (PDP), quando comparada com a topologia DCVS. Em contraste com o conversor Puri, obteve-se uma redução de 32,08% no consumo de energia, 13,26% diminuição no atraso e 15,37% inferior PDP. Além disso, o conversor de nível proposto foi o único capaz de trabalhar a 35% da tensão nominal de alimentação. / Multiple Voltage Digital Systems exploit the concept of voltage scaling by applying different supplies to particular regions of the chip. Each of those regions belongs to a power domain and may have two or more supply voltage configurations. Regardless of distinct energy levels on different power domains, the blocks shall process signals with coherent logic levels. In these systems, the Level Shifters (LS) are essential components that act as voltage scaling interfaces between power domains, guaranteeing the correct signal transmission. With the appropriate voltage scaling interface and its proper implementation, we can avoid excessive static and dynamic power consumption. Therefore, the design and implementation of level shifters should be a conscientious process and must guarantee the lowest overhead in size, energy consumption, and delay time. In this work, we study the main characteristics of voltage scaling interfaces and introduce an energy-efficient level shifter with reduced area, and suitable for low-to-high level conversion. We present the level shifters with the best performance that we found in the literature and categorize them into two main groups: Dual-rail and Single-rail, according to the number of power rails required. The proposed circuit was compared to the traditional topology of each group, Differential Cascode Voltage Switch (DCVS) and Puri’s level shifter respectively. Simulations on an IBMTM 130nm CMOS technology show that the proposed topology requires up to 93.79% less energy under certain conditions. It presented 88.03% smaller delay and 39.6% less Power-Delay Product (PDP) when compared to the DCVS topology. In contrast with the Puri’s level shifter, we obtained a reduction of 32.08% in power consumption, 13.26% smaller delay and 15.37% lower PDP. Besides, our level shifter was the only one capable of working at 35% of the nominal supply voltage.

<p>Analog-to-digital converters (ADC) targeted for use in medical implant devices serve an important role as the interface between analog signal and digital processing system. Usually, low power consumption is required for a long battery lifetime. In such application which requires low power consumption and moderate speed and resolution, one of the most prevalently used ADC architectures is the successive approximation register (SAR) ADC.This thesis presents a design of an ultra-low power 9-bit SAR ADC in 0.13μm CMOS technology. Based on a literature review of SAR ADC design, the proposed SAR ADC combines a capacitive DAC with S/H circuit, uses a binary-weighted capacitor array for the DAC and utilizes a dynamic latch comparator. Evaluation results show that at a supply voltage of 1.2V and an output rate of 1kS/s, the SAR ADC performs a total power consumption of 103nW and a signal-to-noise-and-distortion ratio of 54.4dB. Proper performance is achieved down to a supply voltage of 0.45V, with a power consumption of 16nW.</p>

Analog-to-digital converters (ADC) targeted for use in medical implant devices serve an important role as the interface between analog signal and digital processing system. Usually, low power consumption is required for a long battery lifetime. In such application which requires low power consumption and moderate speed and resolution, one of the most prevalently used ADC architectures is the successive approximation register (SAR) ADC.This thesis presents a design of an ultra-low power 9-bit SAR ADC in 0.13μm CMOS technology. Based on a literature review of SAR ADC design, the proposed SAR ADC combines a capacitive DAC with S/H circuit, uses a binary-weighted capacitor array for the DAC and utilizes a dynamic latch comparator. Evaluation results show that at a supply voltage of 1.2V and an output rate of 1kS/s, the SAR ADC performs a total power consumption of 103nW and a signal-to-noise-and-distortion ratio of 54.4dB. Proper performance is achieved down to a supply voltage of 0.45V, with a power consumption of 16nW.

In the recent years, governments have encouraged the utilization of renewable energy by providing incentives to investors, and enhancing traditional practices in the sector. For example, in Ontario, Canada, local distribution companies can now legally own and operate up to 10 MW generating plant per location as long as it is from a renewable source. Although this trend results in some operational benefits for the host networks, it also creates specific technical challenges and economic problems. New modeling approaches are needed to account for the main features of power produced by these facilities, namely, the uncertainty and uncontrollability. The uncertainty of power produced by weather-based generating facilities affects the decisions of different activities related to the operation of distribution systems. Examples of these tasks include power procurement decisions, the assessment of voltage magnitude variation, and reactive power management. If not properly included, uncertainty could result in non optimal outcome of operational activities of a distribution system operator. Based on different optimization techniques, the thesis introduces several models that capture the uncertain behavior of renewable resources. Two operational tasks were selected for application using the enhanced models: economical operation of distribution system and impact assessment on voltage magnitude. The power procurement problem is an operational challenge to acquire the correct economic mix of power purchases to supply the demand of a local distribution company. Three models have been presented to formulate the power procurement problem with a consideration of the stochastic nature of renewable generation. These models select the optimal quantities of bilateral contracts under uncertain renewable generation and give the option to decision makers to recalculate the powers from other sources. In one of these proposed models, the mean-variance theory is utilized to evaluate the risk associated with the variation of renewable power output on the financial efficiency of a local distribution company. Unlike previous studies, in which renewable power production is identified as a decision variable, in this work the generation from these units is represented as a parameter to model their feature of uncontrollability. Comparison of results obtained from using the proposed models showed that the degree of uncertainty plays an important role in selecting the proper mix. In general, stochastic based algorithms are superior to deterministic approaches when increasing contributions from renewable resources are considered. A major technical problem that may be caused by the uncertain generation of renewable units is the increase of voltage variation. The second part of the thesis introduces a methodology based on a Monte-Carlo technique to assess new installation depending on its impact on the quality of supply voltage. Two different standard measures for supply voltage quality are applied in this approach to provide the decision maker a tool that can be used to authorize new connections of renewable generation. The consistency of results obtained by the two indices applied in the proposed methodology encourages adopting the proposed approach for evaluating the impact of new connections of renewable resources. The models proposed in the thesis contribute to promote safer integration of renewable resources in distribution systems by modeling two main features: uncertainty and non-controllability.

In the recent years, governments have encouraged the utilization of renewable energy by providing incentives to investors, and enhancing traditional practices in the sector. For example, in Ontario, Canada, local distribution companies can now legally own and operate up to 10 MW generating plant per location as long as it is from a renewable source. Although this trend results in some operational benefits for the host networks, it also creates specific technical challenges and economic problems. New modeling approaches are needed to account for the main features of power produced by these facilities, namely, the uncertainty and uncontrollability. The uncertainty of power produced by weather-based generating facilities affects the decisions of different activities related to the operation of distribution systems. Examples of these tasks include power procurement decisions, the assessment of voltage magnitude variation, and reactive power management. If not properly included, uncertainty could result in non optimal outcome of operational activities of a distribution system operator. Based on different optimization techniques, the thesis introduces several models that capture the uncertain behavior of renewable resources. Two operational tasks were selected for application using the enhanced models: economical operation of distribution system and impact assessment on voltage magnitude. The power procurement problem is an operational challenge to acquire the correct economic mix of power purchases to supply the demand of a local distribution company. Three models have been presented to formulate the power procurement problem with a consideration of the stochastic nature of renewable generation. These models select the optimal quantities of bilateral contracts under uncertain renewable generation and give the option to decision makers to recalculate the powers from other sources. In one of these proposed models, the mean-variance theory is utilized to evaluate the risk associated with the variation of renewable power output on the financial efficiency of a local distribution company. Unlike previous studies, in which renewable power production is identified as a decision variable, in this work the generation from these units is represented as a parameter to model their feature of uncontrollability. Comparison of results obtained from using the proposed models showed that the degree of uncertainty plays an important role in selecting the proper mix. In general, stochastic based algorithms are superior to deterministic approaches when increasing contributions from renewable resources are considered. A major technical problem that may be caused by the uncertain generation of renewable units is the increase of voltage variation. The second part of the thesis introduces a methodology based on a Monte-Carlo technique to assess new installation depending on its impact on the quality of supply voltage. Two different standard measures for supply voltage quality are applied in this approach to provide the decision maker a tool that can be used to authorize new connections of renewable generation. The consistency of results obtained by the two indices applied in the proposed methodology encourages adopting the proposed approach for evaluating the impact of new connections of renewable resources. The models proposed in the thesis contribute to promote safer integration of renewable resources in distribution systems by modeling two main features: uncertainty and non-controllability.