A low power low noise amplifier employing negative feedback and current reuse techniques. (March 2016) - Jafarnejad, Roya
Abstract: This paper presents a low power wideband differential Low Noise Amplifier (LNA) suited for multimode receivers and Wireless Sensor Networks (WSN) in a 0.18 μm CMOS technology. By using negative feedback, the stringent trade-off between the input matching and the transconductance ( gm ) is broken and the required transconductance of input transistor in Common-Gate (CG) LNA is decreased. As a result of this and also using the current reuse implementation scheme, power consumption (PDC ) is significantly reduced. The circuit provides high gain and decreased Noise Figure (NF) in spite of low PDC . The LNA structure is fully inductorless, and the core circuit consumes only 1.3 mW from a 1.8-V supply occupying an area of 0.032 mm 2 . A maximum voltage gain of 20.1 dB is provided with 3 dB bandwidth up to 3.3 GHz. The input matching is better than −16 dB from 20 MHz to 3.3 GHz. The minimum NF is 3.2 dB with third order Input Intercept Point (IIP3 ) of −2.4 dBm. Highlights: A 1.3 mW, inductorless differential Common Gate Low Noise Amplifier is presented in this paper. The idea is to remove the stringent trade-off between the input matching and power consumption by using the transconductance of the tail transistor. Unlike gm-boosting, the proposed technique doesn't degrade the linearity. The circuit is low power, low active area and wideband, so it's suitable for multimode and Wireless Sensor Network applications.