DTXCO thermal converter realized by means of a metal film temperature sensor deposited on the crystal plate
V.P. Bagayev, Boris P. Ionov, Sergey A. Zavyalov · 2002
Temperature compensated crystal oscillator parameters are dependent to great extent on the accuracy of crystal temperature measurements. The most prominent results were attained for DTCXO with resonator-temperature sensitive element configuration based on dual-mode excitation principle. In this case parameter high stability is attained and the temperature lag between temperature sensor and a measurement object is practically avoided. The investigation of an alternative crystal temperature measurement procedure shows that high DTCXO performances can be attained without dual-mode excitation. A thin metal film deposited along the crystal plate contour is used as a primary thermosensor. To increase the stability and the accuracy of temperature measurement a thermal converter had been developed using the principle of digital-analog system of automatic frequency control. Using by way of example a simple DTCXO with AT-cut crystal and piece-wise compensation function theoretic and experimental investigation were carried out.