Thermally stable oscillator at 2.5 GHz using temperature compensated BAW resonator and its integrated temperature sensor

This paper presents a miniaturized 2.5GHz frequency source based on compensated BAW resonator with its integrated temperature molybdenum sensor assembled on the differential Colpitts oscillator. The presence of silicon dioxide layer having a positive temperature coefficient compared to other layers is used to reduce the resonator's drift. A demonstration oscillator achieves a frequency drift of 40 ppm over a temperature range from -35degC to +85degC. The oscillator's phase noise of -94dBc/Hz at 2 KHz offset from the carrier is reported.