A 10–19.2 GHz LNA Using a Partially Three-Winding Transformer and Class-AB Operation Achieving −5.3 to −2.4 dBm IP1dB for 6G FR3 Receivers

This paper presents a 10–19.2 GHz wideband low-noise amplifier (LNA) that achieves enhanced linearity and low noise by employing a partially three-winding transformer and a differential Class-AB output stage. The partially three-winding transformer in the first stage provides wideband input matching and gain boosting, enabling a low noise figure without relying on resistive feedback. The differential Class-AB second stage improves voltage swing capability and enhances large-signal behavior, resulting in higher IP1dB and robust blocker tolerance across the operating band. The proposed LNA is implemented in a 65-nm CMOS technology as a two-stage architecture. Measurement results demonstrate a 3-dB bandwidth of 10–19.2 GHz, a peak gain of 16.3 dB, a minimum noise figure of 2.13 dB, and a consistent IP1dB ranging from –5.3 to –2.4 dBm while consuming 13 mW from a 1-V supply. The design occupies a compact core area of 0.12 mm².