Figs. 10(a) and (b) show a power transistor operated at junction temperature T1 of 160C with...

 

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Figs. 10(a) and (b) show a power transistor operated at junction temperature T1 of 160°C with the case attached to a heat sink. The heat sink temperature Ts is found to be 85°C. The total thermal resistance OJA =6.75°C/W. If the ambient temperature TA is 25°C, please calculate (a) case temperature Tc and heat sink temperature Ts. (b) thermal resistance 0jc. (c) thermal resistance Ocs. (d) power dissipated, PD in the device. (e) find the maximum power that can be dissipated safely when operated at TA = 60°C. (f) find the temperature of the case when the maximum power that can be dissipated safely at TA = 50°C, with a heat sink that OCA = 7.5°C/W. PD 0 JC 0 cs SA TJ Fig. 10(a) Tc Ts A آمأ PD(W) 60 45 30 15 0 40 80 120 160 Case temperature (°C) Fig. 10(b) Figs. 10(a) and (b) show a power transistor operated at junction temperature T1 of 160°C with the case attached to a heat sink. The heat sink temperature Ts is found to be 85°C. The total thermal resistance OJA =6.75°C/W. If the ambient temperature TA is 25°C, please calculate (a) case temperature Tc and heat sink temperature Ts. (b) thermal resistance 0jc. (c) thermal resistance Ocs. (d) power dissipated, PD in the device. (e) find the maximum power that can be dissipated safely when operated at TA = 60°C. (f) find the temperature of the case when the maximum power that can be dissipated safely at TA = 50°C, with a heat sink that OCA = 7.5°C/W. PD 0 JC 0 cs SA TJ Fig. 10(a) Tc Ts A آمأ PD(W) 60 45 30 15 0 40 80 120 160 Case temperature (°C) Fig. 10(b)

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a Given TJ 160C TS 85C JA 675CW TA 25C Using the thermal ... View the full answer