A low power low noise amplifier employing negative feedback and current reuse techniques

Abstract

This paper presents a low power wideband differential Low Noise Amplifier (LNA) suited for multimode receivers and Wireless Sensor Networks (WSN) in a 0.18μm 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 1.3mW from a 1.8-V supply occupying an area of 0.032mm2. A maximum voltage gain of 20.1dB is provided with 3dB bandwidth up to 3.3GHz. The input matching is better than −16dB from 20MHz to 3.3GHz. The minimum NF is 3.2dB with third order Input Intercept Point (IIP3) of −2.4dBm.