Startup and Frequency Stability in HighFrequency Oscillators

Start-up criteria in harmonic oscillators are explored. Conventional criteria for start-up prediction are shown to be necessary but not always sufficient for high-frequency oscillators, due to the effects of parasitic elements. Design methods are derived to allow design of reliable oscillators with a well-defined frequency of oscillation. The theory is confirmed with the design, fabrication, and characterization of a 2-GHz monolithic LC oscillator.