A power transistor is specified to have a maximum.junction temperature of 150°C. When the device isoperated at this junction temperature with a heatsink, the case temperature is found to be 97°C.The case is attached to the heat sink with a bondhaving a thermal resistance 0CS=0.5°C/W and thethermal resistance of the heat sink OSA =0.1°C/W.If the ambient temperature is 25°C, what is thepower being dissipated in the device? What is thethermal resistance of the device, 8JC, fromjunction to case? Sketch the equivalent circuit andannotate the thermal resistance and temperatures.

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A power transistor is specified to have a maximum junction temperature of 150°C. When the device is operated at this junction temperature with a heat sink, the case temperature is found to be 97°C. The case is attached to the heat sink with a bond having a thermal resistance 8CS=0.5°C/W and the thermal resistance of the heat sink OSA =0.1°C/W. If the ambient temperature is 25°C, what is the power being dissipated in the device? What is the thermal resistance of the device, 8JC, from junction to case? Sketch the equivalent circuit and annotate the thermal resistance and temperatures.

A power transistor is specified to have a maximum junction temperature of 150°C. When the device is operated at this junction temperature with a heat sink, the case temperature is found to be 97°C. The case is attached to the heat sink with a bond having a thermal resistance 8CS=0.5°C/W and the thermal resistance of the heat sink OSA =0.1°C/W. If the ambient temperature is 25°C, what is the power being dissipated in the device? What is the thermal resistance of the device, 8JC, from junction to case? Sketch the equivalent circuit and annotate the thermal resistance and temperatures.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.39P

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