RF Design Tips, Tricks & Tutorials

Egidio Ragonese & Giuseppe Palmisano of STMicroelectronics & University of Catania present a 3-stage transformer-loaded cascode 24-GHz LNA for Automotive Radar. The transformers use a multi-layer interleaved spiral inductor structure. Momentum EM simulation and optimization of inductance and Q-factor are compared to measurements with Cascade Microtech prober, Vector Network Analyzer (VNA) & Noise Figure Analyser. Layout and manufacturing are shown using a differential topology and 0.13um SiGe:C BiCMOS process. Experimental results are compared with several other technologies and topologies.

Three-stage transformer-loaded LNA Topology