Fragmentation Management for HW Multitasking in 2D Reconfigurable Devices: Metrics and Defragmentation Heuristics

Non

A Study of the Robustness Against SEUs of Digital Circuits Implemented with FPGA DSPs

In this paper we present an experimental validation of the reliability increase of digital circuits implemented in XilinxTMFPGAs when they are implemented using the DSPs (Digital Signal Processors) that are available in the reconfigurable device. For this purpose, we have used a fault-injection platform developed by our research group, NESSY [1]. The presented experiments demonstrate that the probability of occurrence of a SEU effect is similar both in the circuits implemented with and without using embedded DSPs. However, the former are more efficient in terms of area usage, which leads to a decrease in the probability of a SEU occurrence

A Methodology to Emulate Single Event Upsets in Flip-Flops using FPGAs through Partial Reconfiguration and Instrumentation

This paper presents a methodology to emulate Single Event Upsets (SEUs) in FPGA flip-flops (FFs). Since the content of a FF is not modifiable through the FPGA configuration memory bits, a dedicated design is required for fault injection in the FFs. The method proposed in this paper is a hybrid approach that combines FPGA partial reconfiguration and extra logic added to the circuit under test, without modifying its operation. This approach has been integrated into a fault-injection platform, named NESSY (Non intrusive ErrorS injection SYstem), developed by our research group. Finally, this paper includes results on a Virtex-5 FPGA demonstrating the validity of the method on the ITC’99 benchmark set and a Feed-Forward Equalization (FFE) filter. In comparison with other approaches in the literature, this methodology reduces the resource consumption introduced to carry out the fault injection in FFs, at the cost of adding very little time overhead (1.6 �μs per fault)

A Study of the Robustness Against SEUs of Digital Circuits Implemented with FPGA DSPs

In this paper we present an experimental validation of the reliability increase of digital circuits implemented in XilinxTMFPGAs when they are implemented using the DSPs (Digital Signal Processors) that are available in the reconfigurable device. For this purpose, we have used a fault-injection platform developed by our research group, NESSY [1]. The presented experiments demonstrate that the probability of occurrence of a SEU effect is similar both in the circuits implemented with and without using embedded DSPs. However, the former are more efficient in terms of area usage, which leads to a decrease in the probability of a SEU occurrence

Analysis of the reconfiguration latency and energy overheads for a Xilinx Virtex-5 FPGA

In this paper we have evaluated the overhead and the tradeoffs of a set of components usually included in a system with run-time partial reconfiguration implemented on a Xilinx Virtex-5. Our analysis shows the benefits of including a scratchpad memory inside the reconfiguration controller in order to improve the efficiency of the reconfiguration process. We have designed a simple controller for this scratchpad that includes support for prefetching and caching in order to further reduce both the energy and latency overhead

Inherent Uncertainty in the Determination of Multiple Event Cross Sections in Radiation Tests

In radiation tests on SRAMs or FPGAs, two or more independent bitflips can be misled with a multiple event if they accidentally occur in neighbor cells. In the past, different tests such as the ``birthday statistics'' have been proposed to estimate the accuracy of the experimental results. In this paper, simple formulae are proposed to determine the expected number of false 2-bit and 3-bit MCUs from the number of bitflips, memory size and the method used to search multiple events. These expressions are validated using Monte Carlo simulations and experimental data. Also, a technique is proposed to refine experimental data and thus partially removing possible false events. Finally, it is demonstrated that there is a physical limit to determine the cross section of memories with arbitrary accuracy from a single experiment

Hardware Implementation of a Fault-Tolerant Hopfield Neural Network on FPGAs

This letter presents an FPGA implementation of a fault-tolerant Hopfield NeuralNetwork (HNN). The robustness of this circuit against Single Event Upsets (SEUs) and Single Event Transients (SETs) has been evaluated. Results show the fault tolerance of the proposed design, compared to a previous non fault- tolerant implementation and a solution based on triple modular redundancy (TMR) of a standard HNN design

SEU Characterization of Three Successive Generations of COTS SRAMs at Ultralow Bias Voltage to 14.2 MeV Neutrons

This paper presents a SEU sensitivity characterization at ultra-low bias voltage of three generations of COTS SRAMs manufactured in 130 nm, 90 nm and 65 nm CMOS processes. For this purpose, radiation tests with 14.2 MeV neutrons were performed for SRAM power supplies ranging from 0.5 V to 3.15 V. The experimental results yielded clear evidences of the SEU sensitivity increase at very low bias voltages. These results have been cross-checked with predictions issued from the modeling tool MUlti-SCAles Single Event Phenomena Predictive Platform (MUSCA-SEP3). Large-scale SELs and SEFIs, observed in the 90-nm and 130-nm SRAMs respectively, are also presented and discussed

Desarrollo de un entrenador digital portátil de bajo coste para introducir a los estudiantes en el mundo y conocimiento de la electrónica digital, que facilite e incentive el aprendizaje autónomo del alumno

Actualmente, las prácticas de laboratorio de diseño digital de la asignatura de Fundamentos de Computadores (que cuenta con más de 500 estudiantes), se realizan sobre entrenadores digitales fijos de alto coste. Esto conlleva a que los estudiantes únicamente pueden desarrollar sus prácticas en dichos laboratorios, la mayor parte del tiempo ocupados por otros grupos o prácticas de otras asignaturas. El objetivo global de este Proyecto Innova-Docencia sería el desarrollo de un entrenador digital portátil, de bajo coste, que se entregase individualmente a los estudiantes para que realicen sus diseños digitales en lugar de en los entrenadores del laboratorio. De esta manera se pone el foco en el estudiante, facilitando e incentivando el aprendizaje autónomo del alumno