Abstract:  High frequency and wide voltage controlled crystal oscillator(VCXO) is widely used in all kinds of receivers and transponders, and the operating temperature range is usually -40℃～+85℃. The frequency temperature stability of this kind of oscillator is easily worse than that of the inner crystal resonator. So, the reason was analyzed, and the method was provided by reasonably controlling the oscillator circuit voltage controlled range and the resonator drive level to improve the high frequency VCXO frequency temperature characteristics. In the end, four  102.3MHz VCXOs were made and tested. The results were better than the performance demands, and sufficiently proved the method validity.

Key words: Voltage controlled crystal oscillator, Frequency temperature stability, High frequency