Optimization of on-chip inductor and its application in low-pass filter

This paper presents the design of on-chip inductor employing Greenhouse theory. The electrical parameter of the inductor is converted to physical dimensions of the inductor by approximate algorithm, and vice versa. Based on the optimization of inductor, an equivalent circuit model of the low-pass filter (LPF) including substrate parasitics is proposed. The designed LPF is fabricated on high-resistivity silicon substrate in conventional CMOS process. Measurements on the three-pole maximally flat low-pass filter give -3dB bandwidth of 977MHz that is close to the nominal design value of 980MHz.