关键词: 限幅低噪声放大器, 增益下降, 故障定位, 安全间距, 失效分析

Abstract: The limiter low noise amplifier (LNA), which is used to amplify the received radio frequency signal, is the key component of the microwave transceiver module. The receiving gain is the key parameter of the limiter LNA, and the decrease of the gain can cause the function failure of the transceiver module. Appearance inspection, multimeter measure, X-ray inspection, scanning electron microscope (SEM), and other analysis methods are used to analyze the reason of gain decrease of a limiter LNA, and the cause of the failure is determined. The results show that the gain decrease is caused by the insufficient safe distance between the PIN diode chip and the shell during the process assembly. The research result has certain reference significance for the production and assembly, inspection and failure analysis of similar products.

Key words: limiterlownoiseamplifier, gainreduction, faultlocalization, safedistance, failureanalysis