An inductorless wideband noise-cancelling CMOS low noise amplifier with variable-gain technique for DTV tuner application

In this paper, we propose an inductorless CMOS wideband low noise amplifier (LNA), operated in the range from 100 to 900 MHz, with current reuse, mirror bias, gain control and input matching device using noise-cancellation technologies. The traditional wideband LNAs have different input reflection coefficient parameters (S11) at different gain control modes, and they always implement with inductors for wideband matching. Therefore, the proposed LNA which can save power consumption at low gain mode, and implement without inductor on its design. Moreover, its S11 parameter has smaller variation at different gain control modes. The wideband CMOS LNA for digital video broadcasting-handheld (DVB-H), terrestrial-digital multimedia broadcasting (T-DMB), and digital video broadcasting-cable (DVB-C) tuner application is designed using TSMC 0.18-μm0.18-μm RF CMOS process. The post-simulation results at high gain mode show that the gain is 13–15.8dB, the noise figure (NF) is less than 2.75 dB. The LNA consumes power between 7.25 mW (low gain mode) and 17.8 mW (high gain mode) at 1.8 V power supply. The core area is 0.435×0.67mm2.