Modeling of T-model equivalent circuit for spiral inductors in 90 nm CMOS technology

This paper presents a newly proposed T-model of spiral inductors in 90nm radio frequency (RF) CMOS technology. Inductor modeling is one of the most difficult problems facing silicon-based RF integrated circuit designers, and the inclusion of many parameters of the inductor equivalent circuit consumes a lot of time during circuit simulation. In this paper, two models of spiral inductors were simulated to compare their agreement with the measured data from 100MHz to 10GHz. The proposed T-model had less parameters than the conventional double-π model, and also showed good agreement in the RF performance of the spiral inductors, such as quality factor (Q-factor) and inductance (L). In addition, the proposed T-model had an error rate of less than 5% with the S-parameter of measured data, similar to the double-π model.

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