An On-chip PVT Resilient Short Time Measurement Technique

As the CMOS technology nodes continue to shrink, the challenges of developing manufacturing tests for integrated circuits become more difficult to address. To detect parametric faults of new generation of integrated circuits such as 3D ICs, on-chip short-time intervals have to be accurately measured. The accuracy of an on-chip time measurement module is heavily affected by Process, supply Voltage, and Temperature (PVT) variations. This work presents a new on-chip time measurement scheme where the undesired effects of PVT variations are attenuated significantly. To overcome the effects of PVT variations on short-time measurement, phase locking methodology is utilized to implement a robust Vernier delay line. A prototype Time-to-Digital Converter (TDC) has been fabricated using TSMC 0.180 µm CMOS technology and experimental measurements have been carried out to verify the performance parameters of the TDC. The measurement results indicate that the proposed solution reduces the effects of PVT variations by more than tenfold compared to a conventional on-chip TDC. A coarse-fine time interval measurement scheme which is resilient to the PVT variations is also proposed. In this approach, two Delay Locked Loops (DLLs) are utilized to minimize the effects of PVT on the measured time intervals. The proposed scheme has been implemented using CMOS 65nm technology. Simulation results using Advanced Design System (ADS) indicate that the measurement resolution varies by less than 0.1ps with ±15% variations of the supply voltage. The proposed method also presents a robust performance against process and temperature variations. The measurement accuracy changes by a maximum of 0.05ps from slow to fast corners. The implemented TDC presents a robust performance against temperature variations too and its measurement accuracy varies a few femto-seconds from -40 ºC to +100 ºC. The principle of robust short-time measurement was used in practice to design and implement a state-of-the-art Coordinate Measuring Machine (CMM) for an industry partner to measure geometrical features of transmission parts with micrometer resolution. The solution developed for the industry partner has resulted in a patent and a product in the market. The on-chip short-time measurement technology has also been utilized to develop a solution to detect Hardware Trojans

Diseño de un algoritmo de estabilizacion de video orientado a la detección de personas

El presente trabajo de tesis tiene como objetivo principal el desarrollo de un algoritmo de estabilización de video robusto y eficiente frente a cambios de escala, rotación e iluminación. La estabilización de video es una etapa de pre procesamiento utilizada para eliminar o reducir el ruido que se adhiere debido a movimientos involuntarios en los videos. Su importancia radica en que procesamientos posteriores requieren de imágenes alineadas y libres de distorsión espacial. El documento está divido en cuatro capítulos descritos a continuación: En el capítulo 1 se presenta la problemática de la estabilización de videos así como las aplicaciones en diversos campos. Se explicará cómo los videos pueden ser afectados por factores ajenos a la cámara. Entre las aplicaciones se mencionarán procesamientos posteriores que requieren estabilización como paso previo y aplicaciones finales en temas de seguridad, industria y entretenimiento. En el capítulo 2 se mencionan las alternativas de solución del problema. Se presentan tanto las alternativas como sus características, ventajas y desventajas. Entre ellas se describen algunas alternativas mecánicas, que involucran equipos y sistemas sofisticados, y alternativas digitales como registro de imágenes, Structure from Motion y Geometría Epipolar. El capítulo 3 describe la metodología a emplear. Se utilizan gráficas, diagramas e imágenes para mostrar de manera sencilla cómo se piensa atacar el problema. Se describen los parámetros utilizados en cada etapa. El capítulo 4 muestra las simulaciones y los resultados del algoritmo implementado. Mediante imágenes se muestra los resultados de las etapas descritas en el capítulo anteriorTesi

Towards attosecond 4D imaging of atomic-scale dynamics by single-electron diffraction

Many physical and chemical processes which define our daily life take place on atomic scales in space and time. Time-resolved electron diffraction is an excellent tool for investigation of atomic-scale structural dynamics (4D imaging) due to the short de Broglie wavelength of fast electrons. This requires electron pulses with durations on the order of femtoseconds or below. Challenges arise from Coulomb repulsion and dispersion of non-relativistic electron wave packets in vacuum, which currently limits the temporal resolution of diffraction experiments to some hundreds of femtoseconds. In order to eventually advance the temporal resolution of electron diffraction into the few-femtosecond range or below, four new concepts are investigated and combined in this work: First, Coulomb repulsion is avoided by using only a single electron per pulse, which does not repel itself but interferes with itself when being diffracted from atoms. Secondly, dispersion control for electron pulses is implemented with time-dependent electric fields at microwave frequencies, compressing the duration of single-electron pulses at the expense of simultaneous energy broadening. Thirdly, a microwave signal used for electron pulse compression is derived from an ultrashort laser pulse train. Optical enhancement allows a temporal synchronization between the microwave field and the laser pulses with a precision below one femtosecond. Fourthly, a cross-correlation between laser and electron pulses is measured in this work with the purpose of determining the possible temporal resolution of diffraction experiments employing compressed single-electron pulses. This novel characterization method uses the principles of a streak camera with optical fields and potentially offers attosecond temporal resolution. These four concepts show a clear path towards improving the temporal resolution of electron diffraction into the few-femtosecond domain or below, which opens the possibility of observing electron densities in motion. In this work, a compressed electron pulse's duration of 28±5 fs full width at half maximum (12±2 fs standard deviation) at a de Broglie wavelength of 0.08 Å is achieved. Currently, this constitutes the shortest electron pulses suitable for diffraction, about sixfold shorter than in previous work. Ultrafast electron diffraction now meets the requirements for investigating the fastest primary processes in molecules and solids with atomic resolution in space and time

Proceedings of the 5th International Workshop on Reconfigurable Communication-centric Systems on Chip 2010 - ReCoSoC\u2710 - May 17-19, 2010 Karlsruhe, Germany. (KIT Scientific Reports ; 7551)

ReCoSoC is intended to be a periodic annual meeting to expose and discuss gathered expertise as well as state of the art research around SoC related topics through plenary invited papers and posters. The workshop aims to provide a prospective view of tomorrow\u27s challenges in the multibillion transistor era, taking into account the emerging techniques and architectures exploring the synergy between flexible on-chip communication and system reconfigurability