In high-frequency, stable signal generation, the Colpitts-type crystal oscillator circuit stands out for its low phase noise and long-term frequency stability, offering a reliable solution, especially for communication systems and precision measuring instruments. In this study, equivalent circuit models of the Colpitts-type crystal oscillator were created, mathematical relationships were obtained, and theoretical analyses were performed. Theoretical models were examined in a simulation environment using OrCAD/PSpice® and NI Multisim® software; numerical analyses were performed with MATLAB R2025b to support the system outputs. Simulation results were validated with experimental data obtained in the laboratory, demonstrating a high agreement between theoretical, simulation, and experimental findings. The results show that the developed models successfully represent the physical system in terms of oscillation startup time, transient behavior, and oscillation band settling times. Furthermore, solutions to practical problems such as startup instabilities and load effects led to the conclusion that the circuit operates reliably and repeatably.
Parlar et al. (Mon,) studied this question.