Hostname: page-component-586b7cd67f-tf8b9 Total loading time: 0 Render date: 2024-11-29T09:50:53.823Z Has data issue: false hasContentIssue false

Thermal Analyses of LED Light Bars and Backlight Modules

Published online by Cambridge University Press:  17 August 2016

M.-Y. Tsai*
Affiliation:
Department of Mechanical EngineeringChang Gung UniversityTaoyuan, Taiwan
C.-Y. Tang
Affiliation:
Department of Mechanical EngineeringChang Gung UniversityTaoyuan, Taiwan
C.-E. Zheng
Affiliation:
Department of Mechanical EngineeringChang Gung UniversityTaoyuan, Taiwan
Y.-Y. Tsai
Affiliation:
Unity Opto Tech. Co.New Taipei, Taiwan
C.-H. Chen
Affiliation:
Unity Opto Tech. Co.New Taipei, Taiwan
*
*Corresponding author ([email protected])
Get access

Abstract

The effects of various parameters, such as thermal properties of substrates, thermal interface materials (TIMs) and heat sinks on the thermal performance of the light emitting diode (LED) light bars and backlight module are investigated experimentally and numerically in terms of junction temperature (Tj) and thermal resistances from junction to air (Rj-a). The results show that the measured Rj-a of the light bars by powering-on five LEDs in the test is different from one by powering-on only one LED, resulting from the extra heat coming from the adjacent LED packages affecting the Tj for the case of powering-on five LEDs. For the modules, Rj-a is significantly reduced by using the heat sinks for all backlight modules, and aluminum and iron heat sinks do not show any obvious difference in heat dissipation along with any substrates and TIMs. Furthermore, both experimental and simulation results show that the thermal conductivity of the substrates are more important and dominant than TIM and heat sink for the Rj-a of the backlight modules concerned, and also demonstrate that the thermal field for the local model can represent the one in full-scale backlight module.

Type
Research Article
Copyright
Copyright © The Society of Theoretical and Applied Mechanics 2017 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Steranka, F. M. et al., “High Power LEDs Technology Status and Market Applications,” Physica Status Solidi (a), 94, pp. 380388 (2002).3.0.CO;2-N>CrossRefGoogle Scholar
2. Arik, M., Petroski, J. and Weaver, S., “Thermal Challenges for the Future Generation Solid State Lighting Applications: Light Emitting Diode,” Proceedings of International Society Conference on Thermal Phenomena, pp. 113120 (2002).Google Scholar
3. Schubert, E. F. and Kim, J. K., “Solid-State Light Sources Getting Smart,” Science, 308, pp. 12741278 (2005).CrossRefGoogle ScholarPubMed
4. Chang, M. H., Das, D., Varde, P.V. and Pecht, M., “Light Emitting Diodes Reliability Review,” Microelectronics Reliability, 52, pp. 762782 (2012).CrossRefGoogle Scholar
5. Narendran, N., Gu, Y., Freyssinier, J., Yu, P. H. and Deng, L., “Solid-state Lighting: Failure Analysis of White LEDs,” Journal of Crystal Growth, pp. 449456 (2004).CrossRefGoogle Scholar
6. Narendran, N. and Gu, Y., “Life of LED-based White Light Sources,” IEEE/OSA Journal of Display Technology, 1, pp. 167170 (2005).CrossRefGoogle Scholar
7. Arik, M., Becker, C., Weaver, S. and Petroski, J., “Thermal Management of LEDs: Package to System,” Proceedings of SPIE, 5187, doi: 10.1117/12.512731 (2004).Google Scholar
8. Cheng, H. H., Huang, D. S. and Lin, M. T., “Heat Dissipation Design and Analysis of High Power LED Array Using the Finite Element Method,” Microelectronics Reliability, 52, pp. 905911 (2012).CrossRefGoogle Scholar
9. Juntunen, E., Sitomaniemi, A., Tapaninen, O., Persons, R., Challingsworth, M. and Heikkinen, V., “Thermal Performance Comparison of Thick-Film Insulated Aluminum Substrates With Metal Core PCBs for High-Power LED Modules,” IEEE Trans. on Components, Packaging and Manufacturing Technology, 2, pp. 19571964 (2012).CrossRefGoogle Scholar
10. Juntunen, E., et al., “Copper-Core MCPCB With Thermal Vias for High-Power COB LED Modules,” IEEE Transactions on Power Electronics, 29, pp. 14101417 (2014).CrossRefGoogle Scholar
11. Yung, K. C., Liem, H., Choy, H.S. and Cai, Z.X., “Thermal Investigation of a High Brightness LED Array Package Assembly for Various Placement Algorithms,” Applied Thermal Engineering, 63, pp. 105118 (2014).CrossRefGoogle Scholar
12. Ye, H., et al., “Electrical-thermal-luminous-chromatic Model of Phos-phor-converted White Light-emitting Diodes,” Applied Thermal Engineering, 63, pp. 588597 (2014).CrossRefGoogle Scholar
13. Wang, C. P., et al., “Analysis of Thermal Resistance Characteristics of Power LED Module,” IEEE Transactions on Electron Devices, 61, pp. 105109 (2014).CrossRefGoogle Scholar
14. Jeong, M. W., Jeon, S. W., Lee, S. H. and Kim, Y., “Effective Heat Dissipation and Geometric Optimization in an LED Module with Aluminum Nitride (AlN) Insulation Plate,” Applied Thermal Engineering, 76, pp. 212219 (2015).CrossRefGoogle Scholar
15. Frank, R., “Semiconductor Junction Thermometers,” The Measurement Instrumentation and Sensor Handbook, Webster, J. G. ed., CRC/IEEE Press, Boca Raton (1999).Google Scholar
16. Siegal, B., “Measurement of Junction Temperature Confirms Package Thermal Design,” LaserFocus-World, http://www.laserfocusworld.com (2003).Google Scholar
17. Tsai, M. Y., Chen, C. H. and Tsai, W. L., “Thermal Resistance and Reliability of High-Power LED Packages under WHTOL and Thermal Shock Tests,” IEEE Transactions on Components and Packaging Technologies, 33, pp. 738746 (2010).CrossRefGoogle Scholar
18. JEDEC Standard EIA/JESD51-2, “Integrated Circuits Thermal Test Method Environmental Conditions Natural Convection (Still Air),” (1995)Google Scholar
19. Tsai, M. Y., Chen, C. H. and Kang, C. S., “Thermal Measurements and Analyses of Low-Cost High-Power LED Package,” Microelectronics Reliability, 52, p. 845854 (2012).CrossRefGoogle Scholar
20. Fu, Y. F., Yang, S. Y., Hung, T. Y., Lee, C. C. and Chiang, K. N., “Light Degradation Test and Design of Thermal Performance for High-power Light-emitting Diodes,” Microelectronics Reliability, 52, pp. 794803 (2012).Google Scholar
21. Anderson, J. D., Computational Fluid Dynamics, McGraw-Hill International Editions, New York (1995).Google Scholar