CA - Completed Projects
PARSIVAL: Parallel High-Throughput Simulations for Efficient Nanoelectronic Design and Test Validation
Design and test validation is one of the most important and complex tasks within modern semi-conductor product development cycles. The design validation process analyzes and assesses a developed design with respect to certain validation targets to ensure its compliance with given specifications and customer requirements. Test validation evaluates the defect coverage obtained by certain test strategies and assesses the quality of the products tested and delivered. The validation targets include both, functional and non-functional properties, as well as the complex interactions and interdependencies between them. The validation means rely mainly on compute-intensive simulations which require more and more highly parallel hardware acceleration. In this project novel methods for versatile simulation-based VLSI design and test validation on high throughput data-parallel architectures will be developed, which enable a wide range of important state-of-the-art validation tasks for large circuits. In general, due to the nature of the design validation processes and due to the massive amount of data involved, parallelism and throughput-optimization are the keys for making design validation feasible for future industrial-sized designs. The main focus and key features lie in the structure of the simulation model, the abstraction level and the used algorithms, as well as their parallelization on data-parallel architectures. The simulation algorithms should be kept simple to run fast, yet accurate enough to produce acceptable and valuable data for cross-layer validation of complex digital systems.
10.2014 - 12.2018, DFG-Project: WU 245/16-1
This project aims to find novel abstraction and algorithm mapping methods to allow highly accurate timing and NFP-aware simulation of multi-million gate circuits on data-parallel architectures such as graphics processing units (GPUs). The expected dramatic speedup compared to the existing state-of-the-art allows fault simulation of millions of faults and thousands of patterns. The increased accuracy of the simulation results allow to optimize test patterns w.r.t. test power and small delay defect coverage in presence of power noise, clock skew or even circuit variations.
01.2015 - 12.2016, DAAD/JSPS PPP Japan Project: #57155440
Dynamically reconfigurable architectures enable a major acceleration of diverse applications by changing and optimizing the structure of the system at runtime. Permanent and transient faults threaten the correct operation of such an architecture. This project aims to increase dependability of runtime reconfigurable systems by a novel system-level strategy for online tests and online adaptation to an impaired state. This will be achieved by (a) scheduling such that tests for reconfigurable resources are executed with minimal performance impact, (b) resource management such that partially faulty resources are used for components which do not require the faulty elements, and (c) online monitoring and error checking. To ensure reliable runtime reconfiguration, each reconfiguration process is thoroughly tested by a novel and efficient combination of online structural and functional tests. Compared to existing fault-tolerance approaches, our proposal avoids the large hardware overhead of structural redundancy schemes. The saved resources are available for further application acceleration. Still, the proposed scheme covers faults in the fabric, in the reconfigured application logic and errors in the process of reconfiguration.
10.2010 - 06.2017, DFG-Project: WU 245/10-1, 10-2, 10-3
Since the beginning of the DFG Cluster of Excellence "Simulation Technology" (SimTech) at the University of Stuttgart in 2008, the Institute of Computer Architecture and Computer Engineering (ITI, RA) is an active part of the research within the Stuttgart Research Center for Simulation Technology (SRC SimTech). The institute's research includes the development of fault tolerant simulation algorithms for new, tightly-coupled many-core computer architectures like GPUs, the acceleration of existing simulations on such architectures, as well as the mapping of complex simulation applications to innovative reconfigurable heterogeneous computer architectures.
Within the research cluster, Hans-Joachim Wunderlich acts as a principal investigator (PI) and he co-coordinates the research activities of the SimTech Project Network PN2 "High-Performance Simulation across Computer Architectures". This project network is unique in terms of its interdisciplinary nature and its interfaces between the participating researchers and projects. Scientists from computer science, chemistry, physics and chemical engineering work together to develop and provide new solutions for some of the major challenges in simulation technology. The classes of computational problems treated within project network PN2 comprise quantum mechanics, molecular mechanics, electronic structure methods, molecular dynamics, Markov-chain Monte-Carlo simulations and polarizable force fields.
06.2008 - 10.2017, SimTech Cluster of Excellence
The main objective of the RM-BIST project is to extend Design for Test (DFT) circuitry, which is primarily used during manufacturing test of VLSI chips, to Design for Reliability (DFR) infrastructure. We take advantage of existing built-in self-test (BIST) circuitry and reuse it during lifetime operation to provide system monitoring and perform reliability prediction. Moreover, the modified BIST infrastructure is used to perform targeted reliability improvements. We identify, monitor, predict, and mitigate errors affecting the system reliability at different time scales to handle various reliability detractors (radiation-induced soft errors, intermittent faults due to process and runtime variations, transistor aging and electromigration). The goal is to provide runtime support for reliability screening and improvement by modifying and reusing existing DFT infrastructure with minimum costs.
07.2012 - 06.2015, DFG-Project: WU 245/13-1
ROCK: Robust Network On Chip Communication Through Hierarchical Online Diagnosis and Reconfiguration
The project ROCK targets the analysis and the prototypical development of robust architectures and associated design practices for Networks-on-Chips. Thereby, it meets the challenges of increased susceptibility of on-chip communication infrastructures against the massive influences caused by escalating integration density. ROCK pursues the strategy of conducting fault detection, online diagnosis und specific reconfiguration to tackle faults in a hierarchical manner throughout all network layers, aiming at selecting an optimal combination of activities over all layers. The quality of potential solutions is measured by their energy-minimal compliance to assurances made with respect to the performability of the network. For this purpose, performability will be defined for the research area of NoCs, incorporating communication performance and fault statistics. Any algorithms and architectures for controlling and performing diagnosis and reconfiguration shall themselves be designed as fault tolerant. Furthermore, their operation shall be transparent to the application processes and minimize interference with regular NoC communication. A wide range of architectures will be investigated based on the enabling technology of NoC fault models and high-level NoC fault simulation.
08.2011 - 12.2015, DFG-Project: WU 245/12-1
Microelectronic circuits suffer from life-time limiting aging. In this project, online in-field methods to assess circuit performance and remaining life-time will be developed to predict failures due to aging processes. Sensors and monitoring infrastructure are used to analyze both operating conditions as well as aging indicators so that a system failure can be early indicated and prevented by technical measures. Novel maintenance concepts based on failure prediction allow for a substantial simplification of established structural fault tolerance measures (e.g. redundancy concepts) even in safety-critical applications since specific counter measures can be applied before an actual aging induced failure. With the aid of such an on-line monitoring the effective life-time of a microelectronic product can be significantly increased at low cost.
03.2011 - 12.2014, DFG-Project: WU 245/11-1
Functionality in embedded systems is more and more realized by integrated hardware / software systems. Typically, these systems are strongly coupled with technical processes, as for instance the control of a vehicle, which show time-dependent, discrete-continuous dynamics. Testing for the correct functionality of their according design as well as of the final product contributes large sums to the production costs due to its complexity. An efficient method is required for the integrated test of hardware and software in these systems, which respects all the aspects of validation, debug, test and diadnosis. Model-based development and test gains importance in research and also in industrial practice, as they support the systematic, stepwise refinement of requirements down to the implementation. By using models to describe the functionality of integrated hard- and software systems a higher efficiency of their test can be achieved. The central goal of this project is the generation of tests for the functionality and structure of an embedded hardware / software system from its system model along with an automatic evaluation and failure diagnosis.
10.2010 - 09.2013, DFG-Project: WU 245/9-1
In nanoelectronic circuit technology, circuits exhibit a high susceptibility to soft errors not only in memory arrays, but also in memory elements in random logic. Consequently, a goal of this project is the development of an efficient soft error protection scheme that uses both time and space redundancy.
01.2006 - 07.2013, DFG-Project: WU 245/5-1, 5-2
Together, AUDI AG, Continental AG, Infineon Technologies AG and ZMD AG are researching ways to improve the analytic and diagnostic capabilities of electronic control units (ECU) in motor vehicles. Through to 2013, the four partners, headed by Infineon, will work on ways to make error detection more precise and faults easier to rectify for automakers and repair shops. The project partners will be assisted by several research organizations and universities: the Fraunhofer Institute for Integrated Circuits in Dresden, the University of the Federal Armed Forces in Munich, and the Universities of Cottbus, Erlangen-Nuremberg, and Stuttgart.
07.2010 - 07.2013, BMBF - Project
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Hans-Joachim Wunderlich (i.R.)Prof. Dr. rer. nat. habil.
Heading the Research Group Computer Architecture