Publication Date


Document Type


Committee Members

Marian Kazimierczuk (Committee Member), Saiyu Ren (Advisor), Raymond Siferd (Committee Member), Kefu Xue (Committee Member)

Degree Name

Master of Science in Engineering (MSEgr)


A Voltage Controlled Oscillator (VCO) is essentially a tunable frequency generator. A VCO is used as a part in PLL system which is a system that generates a stable oscillating signal. As the digital electronic industry demands an ever increasing performance in speed, VCO's are required to create higher frequency signals. However, the phase noise performance of a VCO decreases as the operating frequency gets higher. The LC VCO is developed in this thesis to be used in with a tunable frequency divider as a part of a PLL system. The LC VCO structure design takes the advantage of a current source in the LC tank to provide an operational condition while lowering the overall tank size for a higher oscillation. The variable frequency divider structure uses the low voltage swing current mode and two CML latch configurations. The dividing constant of the frequency divider is varied by adjusting the load resistance of the CML latches. The resulting combined circuit structure yields a maximum operating frequency of 43.23GHz with the divided frequency of 296MHz. The phase noise of the VCO at maximum operating frequency is - 80dBc/Hz at 1MHz offset.

Page Count


Department or Program

Department of Electrical Engineering

Year Degree Awarded


Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.