The Effects of Die Attach and PCB on LED Package
2014
Hochschulschrift
Zugriff:
102
In this paper, the effects of Die attach and PCB on LED package. Thermal conductivity is the material obstacles to the temperature effect. Thermal resistance units of ℃/W. It means when driven light emitting diodes, steady-state heat conduction, wafer surface temperature dissipation per W. Light-emitting diodes PN junction temperature and the temperature difference between the lead frame per W, or connection PCB substrate the temperature difference between ambient temperature per W, it is LED’s thermal resistance. Mentioned in this paper were junction to lead frame temperature difference per W call Rj-s, junction to ambient temperature difference per W call Rj-a. Wherein Tj is a light-emitting diode PN junction temperature, Ts is the temperature of the lead frame with PCB contacts, Ta is the ambient temperature. To modeled using the finite elements method to analyze. then use Thermal resistance tester, Respectively, use four different thermal conductivity of die bonding process with the three kinds of PCB material analysis measurements which Tj. Explore for light-emitting diodes Rj-s, Rj-a difference, thereby affecting different package emitting diodes, Tj and optical efficiency and lifetime. The maximum difference between the study Tj about 100 ℃, the steady-state maximum difference of brightness 26%, CIE Shift ccx, ccy difference of approximately 0.0245,0.0296. Approximately 23,000 hrs lifetime may increase to 73,000 hrs. The experimental results show that the thermal conductivity difference does affect the luminous efficiency and lifetime. And temperature simulation and experimental results are close, the follow-up if the new material can simulate the ways ahead to confirm its effectiveness.
Titel: |
The Effects of Die Attach and PCB on LED Package
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Autor/in / Beteiligte Person: | Tsao, Yu-Ming ; 曹育銘 |
Link: | |
Veröffentlichung: | 2014 |
Medientyp: | Hochschulschrift |
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