An FPGA Noise Resistant Digital Temperature Sensor with Auto Calibration

In recent years, thermal sensing in digital devices has become increasingly important. From a security perspective, new thermal-based attacks have revealed vulnerabilities in digital devices. Traditional temperature sensors using analog-to-digital converters consume significant power and are not conducive to rapid development. As a result, there has been an escalating demand for low cost, low power digital temperature sensors that can be seamlessly integrated onto digital devices. This research seeks to create a modular Field Programmable Gate Array digital temperature sensor with auto one-point calibration to eliminate the excessive costs and time associated with calibrating existing digital temperature sensors. In addition, to support the auxiliary protection role, the sensor is evaluated alongside a RSA circuit implemented on the same chip, with methods developed to mitigate noise and power fluctuations introduced by the main circuit. The result is a digital temperature sensor resistant to noise and suitable for quick mass deployment in digital devices

A selection method of ring oscillators for an on-chip digital temperature and voltage sensor

An on-chip digital sensor using three types of ring oscillators (ROs: Ring Oscillators) has been proposed to measure temperature and voltage of a VLSI. Each RO has inherent frequency characteristics with respect to temperature and voltage, which differ from those of the other two ROs. Measurement accuracy of the sensor depends on the combination of the ROs. This paper proposes a RO-selection method for the sensor with high accuracy. The proposed method takes particular note of temperature or voltage sensitivity as well as linearity of the RO characteristics. Evaluation experiments with SPICE simulation in 65 nm CMOS technology show that the temperature and voltage accuracies of the sensor are 2.744°C and 3.825mV, respectively, and the selected combination was a nearly optimal from a menu of many different ROs.The 3rd International Test Conference in Asia (ITC-Asia 2019), September 3-5, 2019Tokyo Denki University, Tokyo, Japa

On Evaluation for Aging-Tolerant Ring Oscillators with Accelerated Life Test and Its Application to A Digital Sensor

An aging-tolerant ring oscillator (RO) has been proposed for a digital temperature and voltage sensor. This paper discusses on the effectiveness of aging-tolerance of the ROs through accelerated life test for a test chip with 65nm CMOS technology. The progress of delay degradation of the ROs is examined, and influence of delay degradation on measurement accuracy of the sensor is investigated. Experimental results show that the aging-tolerant ROs can mitigate delay degradation, and that the measurement errors of the sensor can be reduced. Compared with a sensor consisting of an aging-intolerant RO, temperature and voltage errors are reduced 2.5°C and 32mV, respectively.29th IEEE Asian Test Symposium (ATS\u2720), November 22-25, 2020, Penang, Malaysia（オンライン開催に変更

공정 변화에 둔감한 자동 온도 보상 셀프 리프레쉬용 모바일 디램 온도계

학위논문 (박사)-- 서울대학교 대학원 : 전기·컴퓨터공학부, 2013. 8. 김수환.Smaller transistors mean that capacitors are charged less uniformly, which increases the self-refresh current in the DRAMs used in mobile devices. Adaptive self-refresh using an on-chip thermometer can solve this problem. In this thesis, a PVT tolerant on-chip CMOS thermometer specifically designed for controlling the refresh period of a DRAM will be proposed for low power mobile DRAM. Two types of on-chip CMOS thermometer including a novel temperature sensor is proposed, which is implemented in two different DRAM process technologies integrated into mobile LPDDR2 and LPDDR3 products. The on-chip thermometer incorporating in mobile LPDDR2 chip is fabricated in a 44nm DRAM process with a supply of 1.1V. The sensor has a temperature sensitivity of −3.2mV/°C, over a range of 0°C to 110°C. Its resolution is 1.94°C and is only limited by the 6.2mV step of the associated resistor ladder not by its own design. The high linearity of the sensor permits one-point calibration, after which the errors in 61 sample circuits ranged between −1.42°C and +2.66°C. The sensor has an active area of 0.001725mm2 and consumes less than 0.36μW on average with a supply of 1.1V. To improve the overall performance including ultra-low operation voltage, temperature sensitivity, low power consumption, high linearity regardless of process skew variations and high productivity improved by one point calibration, the folded type on-chip thermometer incorporating in mobile LPDDR3 chip which fabricated in a 29nm DRAM process with a supply of 1.1V and 0.8V will be proposed. This folded type sensor exhibits further upgrading properties such as a temperature sensitivity of −3.2mV/°[email protected] &−3.13mV/°C @0.8V, over wide range of -40°C to 110°C. Its resolution is 1.85°[email protected] & 1.98°[email protected] and is only limited by the 6.2mV step. The more linearity of folded type sensor permits one-point calibration, after which the errors in 494 sample circuits ranged between −1.94°C and +1.61°C. The folded type sensor has an active area of 0.001606mm2 and consumes less than 0.19μ[email protected] & 0.14μ[email protected] on average slightly more than unfolded type sensor.ABSTRACT I CONTENTS III LIST OF FIGURES V LIST OF TABLES IX CHAPTER 1 INTRODUCTION 1 1.1 MOTIVATION 1 1.2 THESIS ORGANIZATION 3 CHAPTER 2 ARCHITECTURE OF THERMOMETER 5 2.1 INTRODUCTION TO ON-CHIP THERMOMETER IN MOBILE DRAM 5 2.2 PROPOSED ON-CHIP CMOS THERMOMETER ARCHITECTURE 17 2.3 TEMPERATURE READOUT PROCEDURE OF PROPOSED ON-CHIP CMOS THERMOMETER 23 2.4 PROPOSED FOLDED TYPE ON-CHIP CMOS THERMOMETER ARCHITECTURE 25 2.5 TEMPERATURE READOUT PROCEDURE OF PROPOSED FOLDED TYPE ON-CHIP CMOS THERMOMETER 30 2.6 ONE-POINT CALIBRATION METHOD 32 2.7 TEMPERATURE LINEARITY OF TEMPERATURE SENSOR 35 CHAPTER 3 OPERATIONAL PRINCIPLES OF CMOS TEMPERATURE SENSOR IN MOBILE DRAM 39 3.1 PRIOR WORKS OF ON-CHIP THERMOMETER 39 3.2 PROPOSED CMOS TEMPERATURE SENSOR IN MOBILE DRAM 44 3.3 OPERATION PRINCIPLES OF PROPOSED TEMPERATURE SENSOR 48 3.4 PROPOSED FOLDED TYPE TEMPERATURE SENSOR 55 CHAPTER 4 PERIPHERAL CIRCUITS OF THERMOMETER 60 4.1 REGULATOR FOR VLTCSR SUPPLY 61 4.1.1 DC ANALYSIS 62 4.1.2 AC ANALYSIS 63 4.2 RESISTOR DECK 67 4.3 COMPARATOR 68 CHAPTER 5 EXPERIMENTAL RESULTS 70 5.1 ON-CHIP CMOS THERMOMETER IN 44NM CMOS PROCESS FOR MOBILE LPDDR2 74 5.2 FOLDED TYPE ON-CHIP CMOS THERMOMETER IN 29NM CMOS PROCESS FOR MOBILE LPDDR3 77 CHAPTER 6 CONCLUSIONS 83 BIBLIOGRAPHY 86 ABSTRACT IN KOREAN 89Docto

Fluorescence Resonance Energy Transfer (FRET) Based Sensors for Bioanalysis

The objective of my PhD study was to develop and characterize new methods and sensors based on fluorescence resonance energy transfer (FRET) for bioanalysis. Chapter 3 describes the use of FRET between donor fluorophores and acceptor labeled murine macrophage cells. FRET microscopy was used to determine whether the donor molecules truly permeate through the cell membrane or only adsorb to the cell surface. This method was found to be partially successful since the donor red tail fluorescence overlapped with the sensitized acceptor fluorescence and led to false reading of FRET. We found that is easier to monitor delivery of acceptor molecules into donor-labeled cells. Using donor labeled cells it was possible to determine whether the acceptor molecules were actually delivered into cells. However, a relatively high acceptor concentration in the hundreds of micromolar level was needed to obtain measurable FRET signals in the 3-D cellular system. The results underscored the need to reduce the dimensionality of FRET systems in order to increase the FRET efficiency between donor and acceptor molecules. Chapter 4 describes the development of FRET sensing lipobeads labeled with donors and their use to evaluate the interactions of acceptor molecules with the phospholipid membrane of FRET sensing lipobeads. The change in the dimensionality of the system in which FRET occurs, improved the sensitivity of our measurements by 3-folds compared to FRET measurements in solution. We concluded that a molecular recognition component had to be added to the sensing particles to further increase their selectivity and sensitivity. Chapter 5 describes the development of FRET trap sensing beads and their use for screening nonfluorescent carbohydrates and glycoproteins. The FRET sensing technique was based on binding between dextran molecules labeled with Texas Red (Dextran-TR) and polystyrene microparticles labeled with Fluorescein tagged Concanavalin A (FITC-ConA). It was found that carbohydrates and glycoproteins inhibit the binding between dextran-TR and FITC-ConA labeled particles. The inhibition effect was concentration dependent thus enabled screening carbohydrates and glycoproteins based on their inhibition potency. The dissertation critically evaluates the performance of FRET microscopy and FRET based sensors in delivery and screening applications

Embedded dynamic programming networks for networks-on-chip

PhD ThesisRelentless technology downscaling and recent technological advancements in three dimensional integrated circuit (3D-IC) provide a promising prospect to realize heterogeneous system-on-chip (SoC) and homogeneous chip multiprocessor (CMP) based on the networks-onchip (NoCs) paradigm with augmented scalability, modularity and performance. In many cases in such systems, scheduling and managing communication resources are the major design and implementation challenges instead of the computing resources. Past research efforts were mainly focused on complex design-time or simple heuristic run-time approaches to deal with the on-chip network resource management with only local or partial information about the network. This could yield poor communication resource utilizations and amortize the benefits of the emerging technologies and design methods. Thus, the provision for efficient run-time resource management in large-scale on-chip systems becomes critical. This thesis proposes a design methodology for a novel run-time resource management infrastructure that can be realized efficiently using a distributed architecture, which closely couples with the distributed NoC infrastructure. The proposed infrastructure exploits the global information and status of the network to optimize and manage the on-chip communication resources at run-time. There are four major contributions in this thesis. First, it presents a novel deadlock detection method that utilizes run-time transitive closure (TC) computation to discover the existence of deadlock-equivalence sets, which imply loops of requests in NoCs. This detection scheme, TC-network, guarantees the discovery of all true-deadlocks without false alarms in contrast to state-of-the-art approximation and heuristic approaches. Second, it investigates the advantages of implementing future on-chip systems using three dimensional (3D) integration and presents the design, fabrication and testing results of a TC-network implemented in a fully stacked three-layer 3D architecture using a through-silicon via (TSV) complementary metal-oxide semiconductor (CMOS) technology. Testing results demonstrate the effectiveness of such a TC-network for deadlock detection with minimal computational delay in a large-scale network. Third, it introduces an adaptive strategy to effectively diffuse heat throughout the three dimensional network-on-chip (3D-NoC) geometry. This strategy employs a dynamic programming technique to select and optimize the direction of data manoeuvre in NoC. It leads to a tool, which is based on the accurate HotSpot thermal model and SystemC cycle accurate model, to simulate the thermal system and evaluate the proposed approach. Fourth, it presents a new dynamic programming-based run-time thermal management (DPRTM) system, including reactive and proactive schemes, to effectively diffuse heat throughout NoC-based CMPs by routing packets through the coolest paths, when the temperature does not exceed chip’s thermal limit. When the thermal limit is exceeded, throttling is employed to mitigate heat in the chip and DPRTM changes its course to avoid throttled paths and to minimize the impact of throttling on chip performance. This thesis enables a new avenue to explore a novel run-time resource management infrastructure for NoCs, in which new methodologies and concepts are proposed to enhance the on-chip networks for future large-scale 3D integration.Iraqi Ministry of Higher Education and Scientific Research (MOHESR)

Fluorescence Resonance Energy Transfer (FRET) Based Sensors for Bioanalysis

The objective of my PhD study was to develop and characterize new methods and sensors based on fluorescence resonance energy transfer (FRET) for bioanalysis. Chapter 3 describes the use of FRET between donor fluorophores and acceptor labeled murine macrophage cells. FRET microscopy was used to determine whether the donor molecules truly permeate through the cell membrane or only adsorb to the cell surface. This method was found to be partially successful since the donor red tail fluorescence overlapped with the sensitized acceptor fluorescence and led to false reading of FRET. We found that is easier to monitor delivery of acceptor molecules into donor-labeled cells. Using donor labeled cells it was possible to determine whether the acceptor molecules were actually delivered into cells. However, a relatively high acceptor concentration in the hundreds of micromolar level was needed to obtain measurable FRET signals in the 3-D cellular system. The results underscored the need to reduce the dimensionality of FRET systems in order to increase the FRET efficiency between donor and acceptor molecules. Chapter 4 describes the development of FRET sensing lipobeads labeled with donors and their use to evaluate the interactions of acceptor molecules with the phospholipid membrane of FRET sensing lipobeads. The change in the dimensionality of the system in which FRET occurs, improved the sensitivity of our measurements by 3-folds compared to FRET measurements in solution. We concluded that a molecular recognition component had to be added to the sensing particles to further increase their selectivity and sensitivity. Chapter 5 describes the development of FRET trap sensing beads and their use for screening nonfluorescent carbohydrates and glycoproteins. The FRET sensing technique was based on binding between dextran molecules labeled with Texas Red (Dextran-TR) and polystyrene microparticles labeled with Fluorescein tagged Concanavalin A (FITC-ConA). It was found that carbohydrates and glycoproteins inhibit the binding between dextran-TR and FITC-ConA labeled particles. The inhibition effect was concentration dependent thus enabled screening carbohydrates and glycoproteins based on their inhibition potency. The dissertation critically evaluates the performance of FRET microscopy and FRET based sensors in delivery and screening applications

Holographic Sensors for the Detection of Liquid Phase Analytes

The aim of this project is to design, fabricate and study experimentally photonic structures created by holographic lithography for application in sensing. The aim is to modify the photonic structures with analyte sensitive materials and view of their application in environmental and biomedical sensing. Two types of photonic structures were investigated in these studies: modified surface relief holographic gratings and volume holographic gratings

Miniaturized Fluorescence Biosensor for Studying Neuronal Events

When developing new techniques to analyze neuro-chemical microenvironments, it is important to realize the incredible variability in the cellular content and the response to stimulation between cells and within a single cell. Conventional analysis techniques yield an average result to describe the content and function of cells. This approach often misses important information since the onset of pathological conditions is always initiated in a small number of cells. New minimally invasive single cell analysis techniques are required for single cell studies in order to gain new insights and understanding of cells\u27 functions. The objective of my Ph.D. study was to fabricate, characterize, and apply submicrometric fluorescence sensors for the analysis of neuron cells. This dissertation will report the fabrication of miniaturized fluorescence sensors for Ca2+, pH and Zn2+ analysis. In the first approach, liposomes (phospholipid vesicles) were used as miniaturized containers for fluorescent sensing reagents. Liposome-based fluorescence sensing technology offers several advantages over commonly used fluorescence sensing techniques including high spatial resolution, protection of the sensing dye from quenchers and high biocompatibility. However, liposome based sensors were found to be unstable in the cellular environment. The second approach was to synthesize submicrometric particle-based fluorescence sensors named lipobeads to replace the fluorescent liposomes in cellular studies. Lipobeads are polystyrene particles that are coated with a phospholipid membrane. One unique advantage of fluorescent sensing lipobeads is the ability to immobilize hydrophobic indicator molecules in the phospholipid membrane. This enables the use of these indicators in aqueous media since the lipobeads are fully water miscible. The lipobeads also proved to be highly biocompatible in cellular studies. This is attributed to their phospholipid bilayer membrane, which is similar in structure to cell membranes. The dissertation will describe the analytical properties of fluorescence sensing lipobeads and their application in studying zinc ion release and pH changes near neuron cells under physiological conditions, conditions of neuronal injury and stress and acidic cortical spreading depression during stroke like conditions