On-Chip GIPD Bandpass Filter Using Synthesized Stepped Impedance Resonators

By utilizing synthesized stepped impedance resonators (SIRs) with high/low-impedance synthesized coplanar waveguides, a novel on-chip three-pole bandpass filter is realized on glass integrated passive device process. The synthesized SIR, formed by quasi-lumped series inductors and MIM capacitors, provides an effective way to utilize the chip area efficiently. The footprint of the miniaturized filter, 0.045 ×0.029 λg², is less than one-third the size of the second smallest one in the literature. The upper stopband, extending from 1.4 f0 to 3.77f0, is also the widest among the reported on-chip SIR filter designs. The |S21| at f0 (4.2 GHz) is -3.2 dB, while the bandwidth is 29%.