A contribution to the VCO modeling and simulation

Voltage-controlled oscillators (VCOs) are at the heart of many electronic systems such as phase-locked loops (PLL), radar, and communication systems. The overall performance of these systems is often limited by the VCO´s parameters and performance. Optimizing system performance requires a complete understanding of the VCO´s characteristics. Most applications require that the VCO operate at one frequency, and then be quickly switched to another frequency where it will stay for some time. The key VCO parameters here are frequency overshoot, settling time, and post-tuning drift. Depending on how often a VCO is switched, these parameters will change. In this paper we describe a model of VCO intended to be used in system modeling in the PSPICE environment. Model is especially designed for study of the VCO´s step response.