Yoshio Maeda

High-stability SAW oscillators with cubic frequency temperature curve and excellent aging characteristics

We describe the realization of oscillators combined with quartzs innate excellent long-term stability of frequency and frequency temperature characteristics by optimization of SAW oscillators design conditions using quartz crystal substrates in application on groove structure. As a result, we could realize SAW oscillator with cubic frequency temperature curve, inflection point temperature of 28°C at is close to a room temperature and extremely small frequency variation of 11ppm in wide temperature range between −40°Cand +85°C. Further, we could get excellent long-term stability lower than 3ppm of frequency variation in 2000 hours high temperature environment test with 85°C. SAW resonator that is making up oscillator has gained good resonance characteristics such as Q=14,700 and CI=12Ω with 400MHz. We realized high-performance SAW oscillator on practical use with characteristics such as low jitter and low phase noise, in addition excelling in frequency temperature characteristics and frequency long-term stability by oscillating fundamental wave in high-frequency range with 100MHz to 700MHz.