Estimation of Non-Reciprocal Behavior and Junction Temperature of an IC LED Driver by Thermal Impedance Matrix Measurement

  IJETT-book-cover  International Journal of Engineering Trends and Technology (IJETT)          
© 2017 by IJETT Journal
Volume-45 Number-6
Year of Publication : 2017
Authors : Norazlina M. S., Dheepan Chakravarthii M. K., Shanmugan S., Mutharasu D., Shahrom Mahmud
DOI :  10.14445/22315381/IJETT-V45P255


Norazlina M. S., Dheepan Chakravarthii M. K., Shanmugan S., Mutharasu D., Shahrom Mahmud "Estimation of Non-Reciprocal Behavior and Junction Temperature of an IC LED Driver by Thermal Impedance Matrix Measurement", International Journal of Engineering Trends and Technology (IJETT), V45(6),262-266 March 2017. ISSN:2231-5381. published by seventh sense research group

The thermal path behaviour of the electronic device is often characterized by considering the single heat source and single junction to ambient thermal resistance. In case of IC drivers, the heat source within the device is multiple due to many integrated components such as transistor, internal resistor, and etc on the single die. Hence the evaluation of IC drivers with multiple heat sources is absolutely necessary for imparting suitable thermal management design within the devices. This study aims at evaluating the factor affecting the thermal performance of the IC driver. In this study, thermal transient measurement method and linear superposition technique have been used to measure the junction temperature of the Device under Test (DUT). Also, the thermal impedance of the DUT has been characterized using structure function extracted from the cooling curve. The obtained result of the thermal impedance showed the non-reciprocal behaviour of the thermal transfer impedance (off-diagonal). In terms of structure function, the total Rth-JA of region A is higher than region B and C. From the linear superposition technique, the junction temperature was calculated which showed that the region A (148.07 °C) showed the higher value compared to region B (132.72 °C) and C (139.46 °C). Therefore, it can be concluded that a single die has multiple heat source which increase exponentially in multiple directions resulting in invariable driver performance and failure. Thus, the presence of multiple heat source in the driver was identified as potential performance affecting factor as it caused non-uniform thermal heat distribution within the driver. The outcome of this study benefits in selection of suitable thermal management technique in IC packages.


[1] Ulrich Steegmuller. (2010, Oct.) Main drivers for LED in modern illumination systems. OSRAM Opto Semiconductor. [Online]. Available:
[2] James Patterson. (2010) Dimming Technique for Switch-Mode LED Drivers.Power Electronics Technology. [Online]. Available:
[3] C. J. Weng. (2009, March) Advanced thermal enhacement and management of LED packages Int. Com. In Heat and Mass Transfer. [Online]. 36(3), pp. 245-248. Available:
[4] Robert, L. (2009) Lifetime of White LEDs. U.S Department of Energy. [Online]. Available:
[5] Krisnamoorthi. S, K. Y. Goh, Desmond Y. R. Chong, R. Kapoor, Anthony Y. S. Sun. (2003, ) Thermal characterization of thermally enhanced QFN Package. Electronics Packaging Technology Conference IEEE. [Online]. Available:
[6] RC law, Raymond Cheang, YW Tan, I.A Azid. (2007, Nov) Thermal Performance Prediction of QFN Packages Using Artificial Neural Network (ANN). International Electronic Manufacturing Technology, IEMT. [Online]. Available:
[7] Application Note. (2014) Thermal Considerations in Package Design and Selection. Integrated Device Technology, Inc. [Online]. Available:
[8] Application Note. (2014, Jan) Package Related Thermal Resistance of LEDs. Osram opto Semiconductors. [Online]. Available:
[9] Thermal Design Considerations. (2000, Apr) Philips Semiconductor. [Online]. Available:
[10] Bret A. Zahn. (1998, March) Steady State Thermal Characterization of Multiple Output Device Using Linear Superposition Theory and a Non-Linear Matrix Multiplier. Fouteenth IEEE SEMI-THERM Symposium. [Online]. Available:
[11] Andras Poppe, Yan Zhang, John Wilson, Gabor Farkas, Peter Szabo, John Parry, Marta Rencz, Vladimir Szekely. (2009) Thermal Measurement and Modelling of Multi-die Packages. IEEE transaction on components and packaging technologies. [Online]. Available:
[12] Lam. K, Wong J. H., and Moo W. S. (2006) Thermal resistance analysis of high power LEDs with multi-chip Package.Electronic components and Technology conference, IEEE. [Online]. Available:
[13] Jian Wen Mah, Boon Kiat Lee, Mutharasu Devarajan. (2015, Sept) Thermal Impedance Measurement on Different Chip Arrangements for Various Multichip LEDs Application. IEEE Transaction on Electron Devices. [Online]. Available:
[14] M. J. Whitehead, C. M. Johnson. (2006, Sept) Junction Temperature Elevation as a Result Cross Coupling in a Multi-Device Power Electronic Module. IEEE Electronic System Integration Technology Conference Dresden, Germany. [Online]. Available:
[15] Eric Quyang, Billy Ahn, Robin Bornoff, Weikun He, Nokibul Islam. (2013, March) Transient Thermal characterization of a fcBGA-H Device. SEMI-THERM. [Online]. Available:
[16] Andras Poppe, Gabor Farkas, John Parry, Peter Szabo, Marta Rencz, Vladimir Szekely. (2007, March) DELPHI Compact Modeling of Stacked Die Package. IEEE SEMI-THERM Symposium. [Online]. Available:

Thermal transient measurement, non-reciprocal, multiple heat source, LED IC driver.