Junction temperature

About: Junction temperature is a research topic. Over the lifetime, 5058 publications have been published within this topic receiving 58643 citations.

Thermal behavior and indirect life test of large-area OLED lighting panels

Abstract: In this work, we studied the thermal behavior and addressed the challenges of life testing of large area OLED devices. In particular, we developed an indirect method to accurately calculate the life time of large-area OLED lighting panels without physically life-testing the panels. Using small area OLEDs with structures identical with the tested panels, we performed the life tests at desired driving current densities at different temperatures and extracted the relationship between junction temperature and the lifetime for the particular device. By measuring the panel junction temperature during operation under the same current density and using the life time measured on small area test devices, we determine the lifetime of the panels based on the thermal dependence. We test this methodology by predicting the life time of white PHOLED panels and then physically testing the panels. The typical result for the lifetime to 80% of the initial luminance (LT80) of the panel at a constant dc current density of 10 mA/cm2 (3800 cd/m2), was predicted to be 526 hours in good agreement with the actual life-test at 10 mA/cm2 of 512 hrs. This good agreement, confirmed in different experiments, validates this novel technique as a practical life time predictor of large-area OLED lighting panels in a time saving manner.

Printed circuit board with high heat dissipation

Abstract: A printed wiring board having electronic circuit devices (13, 44) such as semiconductors including a heat sink forming a housing (32, 36) for the printed wiring board, one of the electronic devices (13) being mounted on one portion (12) of a heat spreader that is formed of a material having high thermal conductivity, another portion (10) of the heat spreader forming a thermal energy flow path to the heat sink, thereby lowering the junction temperature at the electronic device (13) and increasing the reliability of the wiring board.

Thermal Mechanics Based Energy Efficient FIR Filter for Digital Signal Processing

Abstract: Thermal mechanism cover the mechanics of Hit Sink, Airflow mechanics, and Ambient Temperature Mechanism to reduce junction temperature in design of Finite Duration Impulse Response (FIR) Filter. In this work, we are implementing FIR Filter on 28nm FPGA. After implementation of FIR Filter, we analyze the effect of in-built mechanism of Air Flow Controller and their produced Airflow on the junction temperature of FPGA. The mechanism of Ambient Temperature controller also play significant role in leakage power dissipation as well as junction temperature of FPGA. Finally, the mechanical structure of Hit Sink is considered for control of junction temperature of FPGA. There is 73.38% reduction in Leakage Power on 55 C ambient temperature when we increase airflow from 250 LFM to 500 LFM. Along with 500 LFM airflow, if we provide high profile hit sink then there is 78.31% reduction in leakage power. There is 37.68% reduction in junction temperature of FPGA when we increase airflow from 250LFM to 500LFM. Along with 500 LFM airflow, if we provide high profile hit sink then there is 41.76 % reduction in junction temperature on 45C ambient temperature. There is no effect of airflow on clock power. Whereas there is significant reduction in Logic Power, Signal Power, DSPs Power and IOs Power with change in Airflow.

Performance Investigation of Air Velocity Effects on PV Modules under Controlled Conditions

Abstract: Junction temperature of PV modules is one of the key parameters on which the performance of PV modules depends. In the present work, an experimental investigation was carried out to analyze the effects of air velocity on the performance of two PV modules, that is, monocrystalline silicon and polycrystalline silicon under the controlled conditions of a wind tunnel in the presence of an artificial solar simulator. The parameters investigated include the surface temperature variation, power output, and efficiency of PV modules under varying air velocity from near zero (indoor lab. conditions) to 15 m/s. Additionally, the results were also determined at two different module angular positions: at 0° angle, that is, parallel to air direction and at 10° angle with the direction of coming air to consider the effects of tilt angles. Afterwards, the thermal analysis of the modules was performed using Ansys-Fluent in which junction temperature and heat flux of modules were determined by applying appropriate boundary conditions, such as air velocity, heat flux, and solar radiation. Finally, the numerical results are compared with the experiment in terms of junction temperatures of modules and good agreement was found. Additionally, the results showed that the maximum module temperature drops by 17.2°C and the module efficiency and power output increased from 10 to 12% with increasing air velocity.