Terry C. Cisco

A SiGe MMIC 6-bit PIN diode phase shifter

A 6-bit PIN diode phase shifter has been successfully demonstrated at microwave frequencies in a SiGe bipolar technology. A post-silicon polymer dielectric interconnect technology is implemented to achieve low loss microstrip structures on the silicon substrate. The monolithic microwave integrated circuit exhibits flat phase shift, low VSWR, and low insertion loss variation, over the 7- to 11-GHz band. This phase shifter demonstrates the feasibility of integrating SiGe technology into microwave systems.

A SiGe MMIC variable gain cascode amplifier

A silicon-germanium variable gain cascode amplifier has been developed to combine the functionality of an amplifier and an attenuator into one monolithic microwave integrated circuit (MMIC). The cascode amplifier, which was designed for a 7-11 GHz frequency range, achieved a gain of 12.5 dB, an input return loss of 7.5 dB, and an output return loss of 12.5 dB. The cascode amplifier exhibited 16 dB of gain control.

A Compact SPDT Switch in 0.18um CMOS Process With High Linearity and Low Insertion Loss

A compact CMOS SPDT switch fabricated in 0.18 mum BiCMOS technology has been successfully demonstrated at X-Ku-band. The fully integrated chip exhibits a low insertion loss of 1.9 dB and an isolation of 22.5 dB at 17 GHz. By reverse biasing the source/drain (S/D) diode junctions, the switch achieves a PldB of 21 dBm and TOI greater than 30 dB in a very compact structure. The small footprint, along with the performance being comparable to GaAs switches, makes the switch a very attractive, low cost building block circuit for MMIC designs.