Resumen de The influence of microwave pulse width on the thermal burnout effect of an LNA constructed by a GaAs PHEMT
In this paper, the influence of microwave pulse width on the thermal burnout effect of a low noise amplifier (LNA) constructed by a GaAs pseudomorphic high electron mobility transistor (PHEMT) is theoretically analyzed and further verified with simulation and experimental results. By analyzing the electrical procedure and the thermal procedure, a theoretical model of the thermal burnout effect of the studied LNA is established according to the properties of microwave pulses and the structure of the LNA and GaAs PHEMT. Based on the theoretical model, the analytical relationship between the microwave pulse width and the thermal burnout power threshold is further obtained. According to the limitations caused by the approximations in the process of modeling, the available microwave pulse width range for the proposed analytical relationship is more than a nanosecond level and less than a microsecond level. The coefficients of the proposed analytical relationship can be determined by fitting at least two sets of simulation or experimental results, which can greatly reduce the simulation or experimental costs. Finally, the analytical relationship is verified by simulation and experimental results. The results show that the proposed analytical relationship is suitable to estimate the thermal burnout power threshold for a given microwave pulse width within the limit of microwave pulse width range.
