A reliable ultra low power merged LNA and Mixer design for medical implant communication services

摘要

This paper presents an ultra low power merged LNA and Mixer design for MICS (Medical Implant Communication Services) applications. A capacitor cross-coupled common gate LNA is implemented for an easy input matching and reasonable noise performance. The mixer operates in weak inversion, which significantly reduces power consumption and relaxes the voltage headroom without sacrificing the LNA performance. The relaxed voltage headroom enables the stacking of the LNA and the mixer with a low supply voltage of 1.2 V. The merged LNA and mixer consumes only 1.83 mW, and achieves 21.6 dB power gain. A NF of the circuit is 3.55 dB at 1 MHz IF, and the IIP3 is −6.08 dBm.