Accurate design of HBT VCOs with flicker noise up-conversion minimization, using an advanced low-frequency cyclostationary noise model

We present a scalable cyclostationary low frequency noise model of GaInP/GaAs HBT, oriented to oscillator circuits CAD, and its implementation in commercial simulators. In order to verify the validity of the scalable noise model, several MMIC VCOs have been designed in the microwave range from 2GHz up to 24 GHz and processed at UMS foundry. Experimental results have been compared with the predicted one showing an excellent agreement without any retrofitting. They validate the proposed low frequency noise model for multifinger HBTs. To our knowledge it is the first time that VCOs are designed using non linear transistor models including LF cyclostationary noise sources.