Silicon bipolar LNAs in the X and Ku bands

Two fully integrated silicon bipolar LNAs at 8 and 12 GHz are presented. Both circuits provide simultaneous noise and input impedance matching. Resonant loads, designed for 50-Ω output matching, are also included. From an on-wafer test, the 8 and the 12-GHz LNAs exhibit a power gain of 11.5 and 8 dB and a noise figure of 2.6 and 4.7 dB, respectively. This performance was achieved with bias currents as low as 4 mA for each circuit. The two LNAs were fabricated in a 45-GHz pure bipolar technology. The paper explores the noise and input impedance self-matching trend of cascode topology in the X and Ku bands.