OCXO design using composite-heating of the crystal resonator

The design of a composite-heated quartz crystal resonator for OCXO applications is described. A mathematical model of the transient processes in the device is presented and is used to identify the physical and electrical parameters of the resonator providing optimized warm-up time, frequency stability, and power consumption. A prototype resonator exhibiting a warm-up time of 15 s, frequency versus temperature stability better than 3/spl times/10/sup /spl minus/8/, and heating current of about 5 mA is described.<
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