Noise optimization of a broadband LNA for tuner applications

摘要

Based on shunt - series feedback topology, a 10dB broadband low noise amplifier is developed for tuner front end applications. With such gain, low noise operation with high linearity is a challenging specification. In this paper, it is shown that there is a direct relation between gain and minimum noise figure under input/output simultaneous matching condition. The measurement of a packaged device with 3.3V supply gives a noise figure NF of 3.5dB, a gain of 10dB and an OIP3 of 30dBm with a supply current of 38mA.