Topic: Microwave Engineering
A high gain MESFET packaged device of case-to-channel thermal resistance of the device is 4.5 C/Watt provides 8 W RF output power taking 20 W DC power. What will be the channel temperature of the device if the case temperature of the device maintained at 55 C?
- A. 109 C
- B. 145 C
- C. 59.5 C
- D. 91 C
Answer: A. 109 C
Explanation: Θ_{case to channel} = (T_channel - T_case) / (P_in - P_out). 4.5 = (T_channel - 55) / (20 - 8) => T_channel = 55 + 54 = 109 C.