TY - JOUR AU - Szalai, Albin AU - Székely, Vladimir TI - Distributed RC one-ports: Characteristic functions and their relations JF - PERIODICA POLYTECHNICA-ELECTRICAL ENGINEERING AND COMPUTER SCIENCE J2 - PERIOD POLYTECH ELECTR ENG COMP SCI VL - 60 PY - 2016 IS - 3 SP - 171 EP - 177 PG - 7 SN - 2064-5260 DO - 10.3311/PPee.7160 UR - https://m2.mtmt.hu/api/publication/3128441 ID - 3128441 LA - English DB - MTMT ER - TY - CHAP AU - Poppe, András AU - Hegedüs, János AU - Szalai, Albin ED - anon, null TI - Multi-domain modeling of power LEDs based on measured isothermal I-V-L characteristics T2 - Proceedings of the CIE Lighting Quality & Energy Efficiency Conference PB - International Commission on Illumination (CIE) CY - Vienna SN - 9783902842657 PY - 2016 SP - 318 EP - 327 PG - 10 UR - https://m2.mtmt.hu/api/publication/2996728 ID - 2996728 N1 - AB - The multi-domain operation of LEDs characterized by the tight coupling between their electrical, thermal and optical properties manifests not only on chip and package level, but has to be tracked in case of LED products of higher integration level such as LED modules or LED luminaires as well. An option for tracking this operation is to apply so called multi-domain Spice-like models of LEDs, suitable for implementation in circuit simulation programs. In this paper an LED model is presented, capable of calculating the self- heating and the emitted radiant flux of an LED chip along with its forward voltage – forward current characteristics and the temperature dependence thereof. The parameters of this model can be identified directly from combined thermal and radiometric measurements of LEDs, compliant to the most recent LED package level testing standards. LA - English DB - MTMT ER - TY - CHAP AU - Poppe, András AU - Hegedüs, János AU - Szalai, Albin AU - Robin, Bornoff AU - James, Dyson ED - R, Mohammed ED - V, Mulay ED - J, Galloway TI - Creating multi-port thermal network models of LED luminaires for application in system level multi-domain simulation using Spice-like solvers T2 - Proceedings of the 32nd IEEE Semiconductor Thermal Measurement and Management Symposium (SEMI-THERM'16) PB - Institute of Electrical and Electronics Engineers (IEEE) CY - San Jose (CA), California SN - 9781509023363 PY - 2016 SP - 44 EP - 49 PG - 6 DO - 10.1109/SEMI-THERM.2016.7458444 UR - https://m2.mtmt.hu/api/publication/2995166 ID - 2995166 AB - The multi-domain operation of LEDs characterized by the tight coupling between their electrical, thermal and optical properties manifests not only on chip and package level, but has to be tracked on LED products of higher integration level such as LED modules or LED luminaires. At present the system level numerical analysis of such integrated LED products is typically performed by the different design teams dealing with the electrical, thermal and optical design separately. One reason of this practice is the lack of a unified modeling approach in which the right models are used for the chip, package, module and luminaire (system) level. Spice-like LED models can address this issue. The present paper describes how thermal network models of luminaires can be created in an automated way to allow system level multi-domain simulations of complete LED luminaires. LA - English DB - MTMT ER - TY - CHAP AU - Poppe, András AU - Szalai, Albin AU - Hegedüs, János ED - Németh, Zoltán ED - Nagy, Balázs Vince TI - LED-ek multi-domain szimulációs modelljei és azok gyakorlati vonatkozásai T2 - Világítástechnikai Évkönyv 2014-2015 PB - Magyar Elektrotechnikai Egyesület, Világítástechnikai Társaság CY - Budapest PY - 2015 SP - 112 EP - 121 PG - 10 UR - https://m2.mtmt.hu/api/publication/2810731 ID - 2810731 AB - A LED-ek ún. multi-domain modelljei konzisztens módon írják le az eszköz elektromos karakterisztikáját, termikus viselkedését és fénykibocsájtásának főbb jellemzőit. Az ilyen modellek célja az, hogy egy teljesítmény LED működését lehessen vele szimulálni az ún. rendszerszintű tervezés során, ahol jellemzően vagy az elektromos környezet, vagy a mechanikai környezet vagy ezek együttesének kialakítása történik. Tekintve, hogy a végső cél egy adott világítástechnikai feladat megoldása, a rendszer (lámpatest) szintű szimulációra szánt multi-domain modellek egyik fontos feladata az, hogy segítségükkel megállapítható legyen az adott (termikus és elektromos) körülmények között alkalmazott LED üzemi fényárama. Jelen cikkünkben áramkör- szimulációs környezetben (pl. a széles körben ismert Spice-hoz hasonló programokban), illetve lámpatest szintű termikus szimulációra alkalmas programokban (pl. az ún. CFD programokban) használható LED modelleket és az ilyen modellek használatához szükséges paraméterek meghatározásának a módját vázoljuk fel. LA - Hungarian DB - MTMT ER - TY - JOUR AU - Székely, Vladimir AU - Szalai, Albin TI - Transformation between Linear Network Features in Convolution Approach JF - INTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS J2 - INT J CIRC THEOR APP VL - 43 PY - 2015 IS - 1 SP - 94 EP - 110 PG - 17 SN - 0098-9886 DO - 10.1002/cta.1928 UR - https://m2.mtmt.hu/api/publication/2694153 ID - 2694153 N1 - Füzet WoS alapján javítva. LA - English DB - MTMT ER - TY - THES AU - Szalai, Albin TI - Lineáris elosztott RC hálózatok analízise PY - 2014 SP - 65 UR - https://m2.mtmt.hu/api/publication/2862759 ID - 2862759 LA - Hungarian DB - MTMT ER - TY - CHAP AU - Poppe, András AU - Szalai, Albin ED - Paul, Wesling ED - Kathe, Erickson TI - Practical aspects of implementation of a multi-domain LED model T2 - Thirtieth Annual SEMICONDUCTOR THERMAL MEASUREMENT AND MANAGEMENT SYMPOSIUM PB - IEEE CY - New York, New York SN - 9781479943746 PY - 2014 SP - 153 EP - 158 PG - 6 DO - 10.1109/SEMI-THERM.2014.6892232 UR - https://m2.mtmt.hu/api/publication/2698143 ID - 2698143 N1 - Befoglaló mű WoS és MTMT megnevezése nem azonos. Az MTMT-ben 1998 óta standardizált konferenciamegnevezéssel lett a befoglaló mű rögzítve. AB - Based on prior paper on multi-domain modeling of LEDs this paper provides an overview of the implementation issues of such model. On one hand the option of simplifying SPICE like macro models by using a commercial, fully coupled electro-thermal simulator is shown. On the other hand implementation details of an LED model are shown in which the current components responsible for heat dissipation and light emission are described separately. Using the current component responsible for light emission the radiant flux of the LED can be calculated directly. As a novelty in LED multid-domain modeling, using the “efficacy of radiation of the light source” is proposed for modeling the emitted luminous flux. The applicability of this quantity is demonstrated by an example. LA - English DB - MTMT ER - TY - CHAP AU - Szalai, Albin AU - Czirkos, Zoltán AU - Székely, Vladimir ED - International, Workshop on Thermal Investigations of ICs and Microstructures TI - A quasi-SPICE electro-thermal simulator T2 - 18th THERMINIC International Workshop on Thermal Investigations of ICs and Systems PB - EDA Publishing Association CY - Grenoble SN - 9781467318822 PY - 2012 SP - 190 EP - 195 PG - 6 UR - https://m2.mtmt.hu/api/publication/2688135 ID - 2688135 N1 - Befoglaló mű WoS és MTMT megnevezése nem azonos. Az MTMT-ben 1995 óta standardizált konferenciamegnevezéssel lett a befoglaló mű rögzítve. AB - Integrated circuits exhibit coupled electro-thermal phenomena. The circuit elements dissipate heat, which propagates in the chip, rising the temperature of all circuit elements. Since the operation of the latter is temperature dependent, their dissipation will also change. This change results in the variation of the element voltages and currents, causing further changes in the dissipation, etc. Therefore we are facing a pair of couplings: an electronic → thermal one and a thermal → electronic one, meaning that all integrated circuits constitute essentially a mutually coupled electronic and thermal system. In this paper a detailed discussion of the electro- thermal phenomena is presented regarding the practical implementation. The final implementation is a SPICE compatible electro-thermal solver (qSPICE), which implements some of the major industry standard models with extended coupled thermal capabilities. The accuracy of qSPICE is demonstrated on multiple examples. LA - English DB - MTMT ER - TY - JOUR AU - Székely, Vladimir AU - Szalai, Albin TI - Measurement of the Time-Constant Spectrum: Systematic Errors, Correction JF - MICROELECTRONICS JOURNAL J2 - MICROELECTRON J VL - 43 PY - 2012 IS - 11 SP - 904 EP - 907 PG - 4 SN - 0026-2692 DO - 10.1016/j.mejo.2012.05.011 UR - https://m2.mtmt.hu/api/publication/2686137 ID - 2686137 LA - English DB - MTMT ER - TY - CHAP AU - Nagy, Gergely AU - Timár, András AU - Szalai, Albin AU - Kerecsen Istvánné Rencz, Márta AU - Poppe, András ED - Paul, Wesling ED - Kathe, Ericson TI - New simulation approaches supporting temperature-aware design of digital ICs T2 - 2012 28th Annual IEEE Semiconductor Thermal Measurement and Management Symposium (SEMI-THERM) PB - IEEE CY - New York, New York SN - 9781467311113 T3 - PROCEEDINGS, IEEE SEMICONDUCTOR THERMAL MEASUREMENT AND MANAGEMENTSYMPOSIUM, ISSN 1065-2221 PY - 2012 SP - 313 EP - 318 PG - 6 DO - 10.1109/STHERM.2012.6188866 UR - https://m2.mtmt.hu/api/publication/2683177 ID - 2683177 AB - 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. LA - English DB - MTMT ER -