A Linearized Cascode Shut-off Low-Noise Amplifier for Carrier Aggregation Application

Abstract

In-band and out-of-band (OOB) interferences are major design problems in low-noise amplifiers (LNA) used for carrier aggregation (CA) application. This paper discusses the design of a cascode shut-off LNA configuration with high level of linearity using modified derivative superposition method. This configuration can work switchably between legacy and CA mode with minimal degradation in its linearity using load disconnection. The proposed architecture is designed using the RF library of TSMC 65-nm CMOS technology and is tested at Long-Term Evolution (LTE) band 2. The LNA achieved an 18. 6dBm input-referred third-order intercept point (IIP3), 13. 7dB S21 and 1.42 noise figure (NF) in CA mode. In legacy mode, it has attained an IIP3 value of 17. 4dBm, 13. 3dB S21, 1.47 noise figure (NF. It consumed 13mA of current at 2.5-V source in both CA and legacy modes.