Modeling Analysis And Design Of Silicon-based Spiral Inductor

With the development of integrated circuit technology and the rapidly growth of mobile communication market, radio frequency integrated circuit based on CMOS silicon process has been widely used. Spiral inductor is needed in all of the important subelement of the radio frequency integrated circuit. As the unit circuit performance is affected by the silicon-based spiral inductor driectly, it is of great significance to build a accurate and fast physically-based model at high frequency and improve the quality factor. The design of on-chip inductor becomes very important.In the paper, the loss mechanism and the high frequency effect are analyzed in detail. The classical single-Ï€model is introduced. And an improved model is proposed accroding to the single-Ï€model. The calculation methods of the model parameters are derived. A magnetic fields simulation software HFSS is used for the samples analog simulation. Accroding to the analog simulation, the conclusion is drawn that the proposed model could be used in the analysis of the on-chip inductor effectively.A special structure differential configuration of the spiral inductor is modeled and the model parameters extraction is designed. By comparing the results of the analog simulation by HFSS and the results calculated with the designed method, the conclusion is drawn that the differential configuration spiral inductor model could be used in the simulation of the inductor effectively. The parameters'influence on the inductor performance is simulated and analyzed. According to the simulation curves, the optimization rules about the silicon-based spiral inductor are sumarized in the paper.Based on a TSMC 0.18 um CMOS proeess,the spiral inductor model proposed in this paper is used to design the low noise amplifier (LNA) circuit, of which the center frequency is 2.4GHz. The LNA performance is simulated. A comprison of the LNA parameter under using the ideal inductor and the on-chip inductor is carried out. From the simulation result, the LNA achieves input reflection coefficient (S₁₁) of -32dB, reverse isolation (S₁₂) of -41dB, power gain (S₂₁) of 18dB, output reflection coefficient (S₂₂) of -22dB,noise figure (NF) of 2.4 dB,input third-oreder intercept point (IIP3) of -6 dBm and input l dB compression point of 15.6 dBm. The total power dissipation is 12.6 mw.