A broadband LNA and mixer for digital video broadcasting applications using a 0.18-μm CMOS process

In this study, a broadband low noise amplifier (LNA)/mixer for digital video broadcasting-satellite receiver tuner was fabricated by a 0.18-μm complementary metal oxide semiconductor (CMOS) process. The proposed broadband LNA receives positive feedback and incorporates a single-ended differential converter to mixer. Two attenuators are used to obtain good noise performance and high linearity. Moreover, the designed CMOS LNA/mixer achieved gain controls in 3-dB steps, an input second-order intercept of 1.37 dBm, and an input third-order intercept of -3.6 dBm in high-gain low-frequency mode. The 6.4-dB noise of LNA was achieved in the frequency range of 950-2150 MHz. The circuit consumes a total current of 25 mA at a supply voltage of 1.8 V and the chip area of the LNA and the mixer are 0.8 × 0.53 mm² and 0.8 × 0.6 mm², respectively.