Design Of A Fully Monolithic 5G Voltage Controlled Oscillator In SiGe Technology

The explosive growth in wireless communication has driven universities and companies to produce wireless transceivers at low-cost, low-power, and compact solutions. One approach to meet these demands is system-on-a-chip (SOC) integration, where RF/analog and digital circuitry reside on the same chip, creating a mixed-signal environment. Concurrently, there is tremendous incentive to utilize Si-based technologies to leverage existing fabrication and design infrastructure and the corresponding economies of scale. While the SOC approach is attractive, it presents major challenges for circuit designers, particularly in the design of monolithic voltage controlled oscillators (VCO).VCOs are important components in the up or down conversion of RF signals in wireless transceivers. VCOs must have very low phase noise and spurious emissions, and be extremely power efficient to meet system requirements. To meet these specifications, VCOs require high-quality factor (Q) tank circuits and reduction of noise from active devices; however, the lack of high-quality monolithic inductors, along with low noise transistors in traditional Si technologies, has been a limiting factor.This thesis presents the design and characterization of a monolithic 5-6GHz Silicon Germanium (SiGe) differential–Gm core with an inductor-capacitor (LC) tank voltage controlled oscillator (VCO). Circuits were designed using 0.35μm-BiCMOS-SiGe process. The advantages of using BiCMOS-SiGe technology for integrated VCO designs are addressed in detail.The thesis include an introduction to design flow for oscillator implementations. In addition, an overview of characterization of differential dual inductors is given. The oscillators are characterized for tuning range, output power, and phase noise. Trade-offs must be made.Finally,at 3.3-V power supply voltage the power consumption of the VCO core is only 10mW. The simulated phase noise at 1-MHz is -114dBc/Hz. The oscillator is tuned from 5.825 to 5.065GHz with a tuning voltage varying from 0 to 2.2V.