Design and implementation of a sub-threshold wireless BFSK transmitter

Power Consumption in VLSI (Very Large Scale Integrated) circuits is currently a major issue in the semiconductor industry. Power is a first order design constraint in many applications. Several of these applications need extreme low power but do not need high speed. Sub-threshold circuit design can be used in these cases, but at such a low supply voltage these circuits exhibit an exponential sensitivity to process, voltage and temperature (PVT) variations. In this thesis we implement and test a robust sub-threshold design flow which uses circuit level PVT compensation to stabilize circuit performance. This is done by dynamic modulation of the delay of a representative signal in the circuit and then phase locking it with an external reference signal. We design and fabricate a sub-threshold wireless BFSK transmitter chip. The transmitter is specified to transmit baseband signals up to a data rate of 32kbps over a distance of 1000m. In addition to the sub-threshold implementation, we implement the BFSK transmitter using a standard cell methodology on the same die operating at super-threshold voltages on a different voltage domain. Experiments using the fabricated die show that the sub-threshold circuit consumes 19.4x lower power than the traditional standard cell based implementation

Digital Circuit Design Using Floating Gate Transistors

Floating gate (flash) transistors are used exclusively for memory applications today. These applications include SD cards of various form factors, USB flash drives and SSDs. In this thesis, we explore the use of flash transistors to implement digital logic circuits. Since the threshold voltage of flash transistors can be modified at a fine granularity during programming, several advantages are obtained by our flash-based digital circuit design approach. For one, speed binning at the factory can be controlled with precision. Secondly, an IC can be re-programmed in the field, to negate effects such as aging, which has been a significant problem in recent times, particularly for mission-critical applications. Thirdly, unlike a regular MOSFET, which has one threshold voltage level, a flash transistor can have multiple threshold voltage levels. The benefit of having multiple threshold voltage levels in a flash transistor is that it allows the ability to encode more symbols in each device, unlike a regular MOSFET. This allows us to implement multi-valued logic functions natively. In this thesis, we evaluate different flash-based digital circuit design approaches and compare their performance with a traditional CMOS standard cell-based design approach. We begin by evaluating our design approach at the cell level to optimize the design’s delay, power energy and physical area characteristics. The flash-based approach is demonstrated to be better than the CMOS standard cell approach, for these performance metrics. Afterwards, we present the performance of our design approach at the block level. We describe a synthesis flow to decompose a circuit block into a network of interconnected flash-based circuit cells. We also describe techniques to optimize the resulting network of flash-based circuit cells using don’t cares. Our optimization approach distinguishes itself from other optimization techniques that use don’t cares, since it a) targets a flash-based design flow, b) optimizes clusters of logic nodes at once instead of one node at a time, c) attempts to reduce the number of cubes instead of reducing the number of literals in each cube and d) performs optimization on the post-technology mapped netlist which results in a direct improvement in result quality, as compared to pre-technology mapping logic optimization that is typically done in the literature. The resulting network characteristics (delay, power, energy and physical area) are presented. These results are compared with a standard cell-based realization of the same block (obtained using commercial tools) and we demonstrate significant improvements in all the design metrics. We also study flash-based FPGA designs (both static and dynamic), and present the tradeoff of delay, power dissipation and energy consumption of the various designs. Our work differs from previously proposed flash-based FPGAs, since we embed the flash transistors (which store the configuration bits) directly within the logic and interconnect fabrics. We also present a detailed description of how the programming of the configuration bits is accomplished, for all the proposed designs

Digital Circuit Design Using Floating Gate Transistors

Floating gate (flash) transistors are used exclusively for memory applications today. These applications include SD cards of various form factors, USB flash drives and SSDs. In this thesis, we explore the use of flash transistors to implement digital logic circuits. Since the threshold voltage of flash transistors can be modified at a fine granularity during programming, several advantages are obtained by our flash-based digital circuit design approach. For one, speed binning at the factory can be controlled with precision. Secondly, an IC can be re-programmed in the field, to negate effects such as aging, which has been a significant problem in recent times, particularly for mission-critical applications. Thirdly, unlike a regular MOSFET, which has one threshold voltage level, a flash transistor can have multiple threshold voltage levels. The benefit of having multiple threshold voltage levels in a flash transistor is that it allows the ability to encode more symbols in each device, unlike a regular MOSFET. This allows us to implement multi-valued logic functions natively. In this thesis, we evaluate different flash-based digital circuit design approaches and compare their performance with a traditional CMOS standard cell-based design approach. We begin by evaluating our design approach at the cell level to optimize the design’s delay, power energy and physical area characteristics. The flash-based approach is demonstrated to be better than the CMOS standard cell approach, for these performance metrics. Afterwards, we present the performance of our design approach at the block level. We describe a synthesis flow to decompose a circuit block into a network of interconnected flash-based circuit cells. We also describe techniques to optimize the resulting network of flash-based circuit cells using don’t cares. Our optimization approach distinguishes itself from other optimization techniques that use don’t cares, since it a) targets a flash-based design flow, b) optimizes clusters of logic nodes at once instead of one node at a time, c) attempts to reduce the number of cubes instead of reducing the number of literals in each cube and d) performs optimization on the post-technology mapped netlist which results in a direct improvement in result quality, as compared to pre-technology mapping logic optimization that is typically done in the literature. The resulting network characteristics (delay, power, energy and physical area) are presented. These results are compared with a standard cell-based realization of the same block (obtained using commercial tools) and we demonstrate significant improvements in all the design metrics. We also study flash-based FPGA designs (both static and dynamic), and present the tradeoff of delay, power dissipation and energy consumption of the various designs. Our work differs from previously proposed flash-based FPGAs, since we embed the flash transistors (which store the configuration bits) directly within the logic and interconnect fabrics. We also present a detailed description of how the programming of the configuration bits is accomplished, for all the proposed designs

Minimizing and exploiting leakage in VLSI

Power consumption of VLSI (Very Large Scale Integrated) circuits has been growing at an alarmingly rapid rate. This increase in power consumption, coupled with the increasing demand for portable/hand-held electronics, has made power consumption a dominant concern in the design of VLSI circuits today. Traditionally dynamic (switching) power has dominated the total power consumption of VLSI circuits. However, due to process scaling trends, leakage power has now become a major component of the total power consumption in VLSI circuits. This dissertation explores techniques to reduce leakage, as well as techniques to exploit leakage currents through the use of sub-threshold circuits. This dissertation consists of two studies. In the first study, techniques to reduce leakage are presented. These include a low leakage ASIC design methodology that uses high VT sleep transistors selectively, a methodology that combines input vector control and circuit modification, and a scheme to find the optimum reverse body bias voltage to minimize leakage. As the minimum feature size of VLSI fabrication processes continues to shrink with each successive process generation (along with the value of supply voltage and therefore the threshold voltage of the devices), leakage currents increase exponentially. Leakage currents are hence seen as a necessary evil in traditional VLSI design methodologies. We present an approach to turn this problem into an opportunity. In the second study in this dissertation, we attempt to exploit leakage currents to perform computation. We use sub-threshold digital circuits and come up with ways to get around some of the pitfalls associated with sub-threshold circuit design. These include a technique that uses body biasing adaptively to compensate for Process, Voltage and Temperature (PVT) variations, a design approach that uses asynchronous micro-pipelined Network of Programmable Logic Arrays (NPLAs) to help improve the throughput of sub-threshold designs, and a method to find the optimum supply voltage that minimizes energy consumption in a circuit

ОПТИМИЗАЦИОННЫЕ ПРЕОБРАЗОВАНИЯ ЛОГИЧЕСКОЙ СХЕМЫ НА ОСНОВЕ БЛОЧНОГО РАЗБИЕНИЯ

Исследуется возможность использования метода разбиения логических сетей для минимизации сложности логических схем, синтезируемых в системе проектирования Leonardo. Описывается технология проведения эксперимента, полученные экспериментальные результаты представлены в таблицах. Делается вывод об эффективности применения процедуры разбиения для минимизации сложности многоуровневых схем, синтезируемых в библиотеке проектирования базовых матричных кристаллов (БМК)

Studies on physical interconnect technologies in advanced SoC designs

制度:新 ; 文部省報告番号:甲1992号 ; 学位の種類:博士(工学) ; 授与年月日:2005/3/15 ; 早大学位記番号:新392

Ekstraksi Fitur Conflict of Interest pada Artikel Ilmiah Untuk Menentukan Kualitas Citation Author

Sitasi pada publikasi ilmiah mempengaruhi kualitas artikel sehingga akanberpengaruh terhadap kredibilitas author (peneliti). Terda pat banyak cara untuk meningkatkan kredibilitas peneliti, salah satunya adalah dengan melakukan sitasi terhadap diri sendiri (self citation). Namun, proses self citation yang berlebihan mengurangi kualitas sitasi paper tersebut. Terdapat banyak penelitian yang membuat metode untuk mengukur kualitas self-citation yang tidak sesuai, salah satunya dengan menggunakan rasio self-citation pada jendela waktu. Akan tetapi, metode ini tidak mempertimbangkan kesesuaian topik penelitian paper utama terhadap paper yang mensitasinya. Sehingga diperlukan adanya penentuan kualitas sitasi pada author agar dapat diketahui apakah peneliti sering meggunakan citation yang tidak sesuai topiknya berdasarkan paper author dan paper sitasi. Penelitian ini mengusulkan metode ekstraksi fitur conflict of interest untuk menentukan kualitas citation penulis artikel ilmiah. Hal ini dilakukan untuk mengetahui seberapa baik peneliti dalam menggunakan sitasinya. Terdapat 2 fitur yang diusulkan dalam penelitian ini. Pertama, fitur confict of interest yang didapatkan dari konflik kepentingan antara author paper dan author paper yang disitasi. Kedua, fitur similaritas konten yaitu fitur yang didapatkan dari kesamaan topik antar dokumen paper dan yang disitasinya. Metode similaritas yang digunakan adalah salah satu pendekatan deep learning yaitu Siamese Neural Network yang dikombinasikan dengan Long Short Term Memory. Kedua fitur ini selanjutnya diklasifikasi untuk menentukan kualitas citation author. Seluruh fitur akan diuji performanya pada proses klasifikasi. Hasil klasifikasi selanjutnya akan dihitung nilai akurasinya untuk mendapatkan performa fitur yang diusulkan. Hasil uji coba menunjukkan bahwa usulan fitur dapat digunakan untuk mengklasifikasi kualitas sitasi author. Hal ini ditunjukkan dengan nilai akurasi sebesar 66.67% pada klasifikasi Random Forest dan rata-rata akurasi sebesar 62% pada 3 klasifikasi yang digunakan. =================================================================================================== Citation on scientific paper affect on article quality so that it will affect on author credibility. There are many ways to increase the credibility of researchers, one of them is to do a self-citation. However, this process makes the calculation in bibliometric becoming less accurate because it doesn’t consider citation quality. There is some studies that proposed a method to measure an inappropriate self-citation, one of them is using self-citation ratio. But, this method doesnt consider topic relatedness between main paper and cited paper. So, its required to determine author’s citation quality to know that author are using anomalous citation based on main paper and each cited paper. This research proposed feature extraction conflict of interest to detect author’s citation quality. It allows us to know how right an author use citation in publication. Two features are proposed in this research. First, conflict of interest feature, is obtained from interest conflict between paper author and citation’s paper author. Second, content similarity feature, is obtained from the similarity between paper and cited papers of author. Deep learning approach is used to get the similarity of each document. Combination of Siamese neural network and Long Short-Term Memory can provide a better result on similarity based on training data. Last, all features will be combined with self-citation’s count feature based on previous research and classified to detect author’s citation quality. Features will be tested for its performance using classification. From the classification results, accuracy will be calculated to obtain the performance of the proposed feature. Based on the result, proposed feature can be used to classify author’s citation quality. It is shown with 66,67% of accuracy by using Random Forest classification and 62% of average accuracy on 3 classifier

Advances in Bioengineering

The technological approach and the high level of innovation make bioengineering extremely dynamic and this forces researchers to continuous updating. It involves the publication of the results of the latest scientific research. This book covers a wide range of aspects and issues related to advances in bioengineering research with a particular focus on innovative technologies and applications. The book consists of 13 scientific contributions divided in four sections: Materials Science; Biosensors. Electronics and Telemetry; Light Therapy; Computing and Analysis Techniques