A Two-Stage 0.18 µm CMOS Differential Low-Noise Amplifier with Integrated LC Balun for 2.4 GHz Applications

This work aims at designing a two-stage 0.18 µm CMOS differential low-noise amplifier (LNA) with integrated LC balun, operating at 2.4 GHz industrial, scientific, and medical (ISM) band. A differential LNA has an advantage of common mode noise cancelation and enables a narrowband operation. The need of lossy off-chip balun in a differential LNA is overcome by a LC balun integrated at the input. The proposed two-stage differential LNA achieves a gain of 20.9 dB, noise figure of 1.7 dB, and input return loss of −39.2 dB. The proposed LNA is also observed to be stable at 2.4 GHz operating frequency.