A 4.2-9.2GHz Cryogenic Transformer Feedback Low Noise Amplifier with 4.5K Noise Temperature and Noise-Power Matching in 22nm CMOS FDSOI

This paper presents a compact broadband cryogenic low noise amplifier (LNA) with simultaneous noise and power matching with transformer-based feedback. The LNA is composed of an input impedance transforming network and three-stage amplifiers to achieve simultaneous broadband low-noise and power matching. The first stage is a cascode amplifier with a drain source-coupled transformer. The second stage is a current-reuse broadband amplifier, and the third stage is an inductive-peaking cascode common-source amplifier. The LNA is packaged in a custom chassis and measured at 300K and 16K. At 300K probing measurement, the LNA achieves minimum noise Fig. of 1.42dB and S11< -10dB from 3.6-8.2 GHz with 34dB-35.9dB gain. The overall group delay is less than 0.3ns and IIP3 is ≥ -6dBm across the frequency range. At 16K, the LNA achieves a minimum noise Fig. (NF) of 0.065dB and NF < 0.3dB from 4.2-9.2 GHz with 31.4dB-34.7dB gain.