@article{MTMT:2908301, title = {Advancing the thermal stability of 3D ICs using logi-thermal simulation}, url = {https://m2.mtmt.hu/api/publication/2908301}, author = {Nagy, Gergely and Horváth, Péter and Pohl, László and Poppe, András}, doi = {10.1016/j.mejo.2015.06.025}, journal-iso = {MICROELECTRON J}, journal = {MICROELECTRONICS JOURNAL}, volume = {46}, unique-id = {2908301}, issn = {0026-2692}, year = {2015}, eissn = {0959-8324}, pages = {1114-1120}, orcid-numbers = {Horváth, Péter/0000-0002-5926-6650; Pohl, László/0000-0003-2390-1381; Poppe, András/0000-0002-9381-6716} } @inproceedings{MTMT:2743939, title = {Advancing the thermal stability of 3D-IC's using logi-thermal simulation}, url = {https://m2.mtmt.hu/api/publication/2743939}, author = {Nagy, Gergely and Horváth, Péter and Pohl, László and Poppe, András}, booktitle = {20th International Workshop on THERMal INvestigation of ICs and Systems (THERMINIC'14)}, doi = {10.1109/THERMINIC.2014.6972486}, unique-id = {2743939}, abstract = {3D-ICs have emerged in the past few years. While they solve a large number of problems related to scaling, they also create new ones. Removing the heat from the layers far from the cooling facilities is a great challenge still under intensive research. This paper shows how logi-thermal simulation can be used to predict the operation parameters of large digital systems realized in 3D-ICs. The method can be effectively used to guide place-and-route algorithms and to find the thermal bottlenecks.}, year = {2014}, orcid-numbers = {Horváth, Péter/0000-0002-5926-6650; Pohl, László/0000-0003-2390-1381; Poppe, András/0000-0002-9381-6716} } @inproceedings{MTMT:2695008, title = {Practical aspects of thermal transient testing in live digital circuits}, url = {https://m2.mtmt.hu/api/publication/2695008}, author = {Nagy, Gergely and Horváth, Péter and Poppe, András}, booktitle = {19th International Workshop on THERMal INvestigation of ICs and Systems (THERMINIC 2013)}, doi = {10.1109/THERMINIC.2013.6675227}, unique-id = {2695008}, abstract = {Thermal Transient Testing is a method practically used to determine the thermal model of an integrated circuit’s case and cooling facilities. The traditional measurement setup of this diagnostic examination does not allow in-circuit testing in case of fully digital semi-custom devices, such as complex programmable logic devices (CPLDs), field programmable gate arrays (FPGAs) and programmable system on a chip devices (PSoCs) because it demands an accessible on-chip p-n junction for temperature rise initiation and temperature monitoring. The article presents a proposed novel measurement setup of the thermal transient testing developed for programmable logic devices that implements the required measurement means exploiting the general purpose programmable logic fabric. The main objective of the research is to determine the effects of the interaction between a live digital circuit and the thermal transient testing environment in order to ascertain the feasibility of an on-chip thermal testing facility making possible in- circuit measurements. A simple test environment and the obtained measurement results are presented in order to prove the applicability of the proposed measurement method. The article also presents an application of the logi-thermal simulation method enabling designers to optimize the relative placement of the measurement elements and the user logic. Simulation results showing the application of the method are included in this paper as well.}, year = {2013}, pages = {87-91}, orcid-numbers = {Horváth, Péter/0000-0002-5926-6650; Poppe, András/0000-0002-9381-6716} } @inproceedings{MTMT:2687414, title = {Yield enhancement by logi-thermal simulation based testing}, url = {https://m2.mtmt.hu/api/publication/2687414}, author = {Nagy, Gergely and Pohl, László and Timár, András and Poppe, András}, booktitle = {18th THERMINIC International Workshop on Thermal Investigations of ICs and Systems}, unique-id = {2687414}, abstract = {This paper proposes a method for yield enhancement in digital integrated circuit manufacture using a temperature dependent logic simulation tool. In an industrial environment the time slot dedicated to the logic testing of a single integrated circuit needs to be as short as possible in order to boost production. During this short period thermally induced errors might remain hidden due to long thermal time constants. This paper introduces a methodology to determine the steadystate die temperature where a short logic test is able to reveal logic faults. The evolved die temperature is simulated with a logi-thermal simulator engine that performs logic simulation by taking self-heating into account. We propose that the testing should take place at an elevated temperature where the temperature dependent failures arise. This approach makes it possible to detect otherwise hidden defects while keeping testing times short.}, year = {2012}, pages = {196-199}, orcid-numbers = {Pohl, László/0000-0003-2390-1381; Timár, András/0000-0002-4173-1550; Poppe, András/0000-0002-9381-6716} } @inproceedings{MTMT:2684795, title = {Simulation Framework for Multilevel Power Estimation and Timing Analysis of Digital Systems Allowing the Consideration of Thermal Effects}, url = {https://m2.mtmt.hu/api/publication/2684795}, author = {Nagy, Gergely and Poppe, András}, booktitle = {Proceedings of the 13th IEEE Latin-American Test Workshop (LATW'12)}, doi = {10.1109/LATW.2012.6261250}, unique-id = {2684795}, abstract = {This paper presents a simulation framework that considers the self-heating of digital blocks and thus helps designers, verification engineers and test engineers to predict or detect thermally sensitive regions and possible signal integrity issues in complex digital designs. Excessively long simulation times due to the fact that thermal simulation is computationally highly intensive are avoided by effective simulation methods and the capability of the architecture to model parts of the system at different levels of abstraction. This allows engineers to simulate the system throughout the entire design phase starting as early as the high-level architectural design. The abilities of the presented environment can be put to use in the design for testing as it helps the placement of test circuitry to spots and regions in an integrated circuit where the risk of developing thermally induced faults is the highest.}, keywords = {Electro-thermal simulation; Logi-thermal simulation}, year = {2012}, pages = {1-5}, orcid-numbers = {Poppe, András/0000-0002-9381-6716} } @inproceedings{MTMT:2683177, title = {New simulation approaches supporting temperature-aware design of digital ICs}, url = {https://m2.mtmt.hu/api/publication/2683177}, author = {Nagy, Gergely and Timár, András and Szalai, Albin and Kerecsen Istvánné Rencz, Márta and Poppe, András}, booktitle = {2012 28th Annual IEEE Semiconductor Thermal Measurement and Management Symposium (SEMI-THERM)}, doi = {10.1109/STHERM.2012.6188866}, unique-id = {2683177}, abstract = {Regarding thermal issues in digital IC design a major concern is how timing integrity is affected by the elevated junction temperature and temperature gradients on the chip surface. To predict this in a thermal aware design process one needs a dedicated simulation tool in which the logic simulation of the circuit is coupled to the thermal simulation of the chip and its environment. This paper presents two approaches to this so called logi-thermal simulation. In one of our approaches we rely completely on industry standard EDA tools, standard EDA file formats and interfaces. In the other solution which provides us total freedom in the abstraction level of circuit description and simulation accuracy we use our own logic simulation engine. In both cases the logic simulation engine is connected to our own thermal simulation engines which also use compact thermal models of the IC package during simulation. This paper describes certain implementation aspects and features of our logi-thermal simulation solutions, with emphasizes on modeling the thermal properties of the IC packaging.}, year = {2012}, pages = {313-318}, orcid-numbers = {Timár, András/0000-0002-4173-1550; Kerecsen Istvánné Rencz, Márta/0000-0003-4183-3853; Poppe, András/0000-0002-9381-6716} } @inproceedings{MTMT:2668280, title = {A Novel Simulation Environment Enabling Multilevel Power Estimation of Digital Systems}, url = {https://m2.mtmt.hu/api/publication/2668280}, author = {Nagy, Gergely and Poppe, András}, booktitle = {Proceedings of the 17th International Workshop on THERMal INvestigation of ICs and Systems (THERMINIC'11)}, unique-id = {2668280}, abstract = {This paper presents a novel logi-thermal simulator architecture. A logi-thermal simulator encorporates a logic and a thermal core in strong coupling. It is capable of calculating the self-heating of digital blocks and is able to account for the consequences of temperature change by implementing the delays of the blocks as a function of the temperature. The simulator architecture presented is able to work with logic entities described at different levels of abstraction. This allows to simulate a design at a very early phase when only high-level descriptions are available or to simulate systems that have elements in different design phases. Such a feature enables engineers to perform logi-thermal simulation throughout almost the entire design process which allows for the application of multiple-level optimization. It can also be used to shorten simulation times when only some parts of the design need to be simulated in high detail.}, year = {2011}, pages = {149-152}, orcid-numbers = {Poppe, András/0000-0002-9381-6716} } @inproceedings{MTMT:2626539, title = {A Novel Procedure and Device to Allow Comprehensive Characterization of Power LEDs over a Wide Range of Temperature}, url = {https://m2.mtmt.hu/api/publication/2626539}, author = {Gábor, Molnár and Nagy, Gergely and Szűcs, Zoltán}, booktitle = {Proceedings of the 14th International Workshop on THERMal INvestigation of ICs and Systems (THERMINIC'08)}, doi = {10.1109/THERMINIC.2008.4669885}, unique-id = {2626539}, abstract = {LEDs are key elements in modern, energy efiicient lighting solutions as well as impose some issues from thermal point of view, since light output and reliability both depend on LEDs' junction temperature. A comprehensive and accurate measurement method is required and demanded by several leader LED manufacturers. Failing a proper combined thermal and radiometric/photometric characterization of LED light sources it is impossible to fulfill the reliability prescriptions for LEDs and to trust the lifetime estimation given in LED datasheets. Light output of LEDs is typically measured in integrating spheres. A key element in such a total flux measurement setup is the appropriate set of standard LEDs which are both current and temperature stabilized and are accompanied with certificate values of their own total flux tracable to primary etalons of national measurement laboratorise. So far there are hardly any such standard LEDs available for the high power range. In this paper we describe the design of such a device (having 5 colors) and describe a modification of the substitution type total flux measurement method which is suitable for an automated, comprehensive measurement of LEDs over a wide range of operating conditions.}, year = {2008}, pages = {89-92} } @inproceedings{MTMT:2626538, title = {Consideration of Thermal Effects in Logic Simulation}, url = {https://m2.mtmt.hu/api/publication/2626538}, author = {Nagy, Gergely and Horváth, György Gábor and Poppe, András}, booktitle = {Proceedings of the 14th International Workshop on THERMal INvestigation of ICs and Systems (THERMINIC'08)}, doi = {10.1109/THERMINIC.2008.4669914}, unique-id = {2626538}, abstract = {This paper presents a method that considers thermal effects in logic simulations. The aim is to develop a tool that is capable of modeling the thermal behavior of a digital circuit and, at the same time, yields results almost at the speed of ordinary logic simulators. The importance of such a simulation is that thermal effects can be the cause of signal integrity problems. The structure and the basic operation of the simulator are discussed as well as the issues that need to be addressed throughout the development. A detailed description of the implementation of the tightly integrated thermal and logic simulation is also given.}, year = {2008}, pages = {229-234}, orcid-numbers = {Poppe, András/0000-0002-9381-6716} } @inproceedings{MTMT:2613659, title = {Electro-thermal and logi-thermal simulators aimed at the temperature-aware design of complex integrated circuits}, url = {https://m2.mtmt.hu/api/publication/2613659}, author = {Poppe, András and Horváth, György Gábor and Nagy, Gergely and Kerecsen Istvánné Rencz, Márta and Székely, Vladimir}, booktitle = {Proceedings of the 24th IEEE Semiconductor Thermal Measurement and Management Symposium (SEMI-THERM'08)}, doi = {10.1109/STHERM.2008.4509369}, unique-id = {2613659}, year = {2008}, pages = {68-76}, orcid-numbers = {Poppe, András/0000-0002-9381-6716; Kerecsen Istvánné Rencz, Márta/0000-0003-4183-3853} }