JP2005277551A5 - - Google Patents

Claims (8)

A crystal resonator having a temperature characteristic in which the oscillation frequency changes in a cubic function with respect to a temperature change;
A temperature sensor that generates a temperature detection signal whose potential changes in a linear function with respect to a temperature change ;
An inversion circuit for generating an inversion signal obtained by inverting the temperature detection signal around the inflection point of the cubic function temperature characteristic of the crystal unit;
Based on the temperature detection signal, a first active element for generating a first correction signal which varies quadratically,
It said first active element and configured the same, based on said inverted signal, and a second active element for generating a second correction signal which varies quadratically,
A first correction signal and the second correction signal and the temperature compensated crystal oscillator example Bei a variable capacitance element for adjusting an oscillation frequency difference capacitance changes based on the,
By moving the nonlinear spline start points of the first correction signal and the second correction signal that change in a quadratic function in the temperature axis direction using the temperature detection signal and the inverted signal, the crystal Correct the slope of the primary component of the temperature characteristics of the vibrator,
A temperature-compensated crystal oscillator , wherein the oscillation frequency of the crystal resonator is corrected and adjusted to a predetermined standard frequency by moving in the potential axis direction using the temperature detection signal and the inverted signal . 2. The temperature compensated crystal oscillator according to claim 1, wherein the first active element and the second active element are P-channel MOS transistors.   The temperature according to claim 2, wherein the first input signal is input to a source of the first MOS transistor, and the second input signal is input to a source of the second MOS transistor. Compensated crystal oscillator.   4. The same bias potential that matches the primary temperature characteristic of the crystal resonator is applied to the gate of the first MOS transistor and the gate of the second MOS transistor. A temperature-compensated crystal oscillator described in 1.   3. The temperature according to claim 2, wherein the first input signal is input to a gate of the first MOS transistor, and the second input signal is input to a gate of the second MOS transistor. Compensated crystal oscillator.   6. The same bias potential that matches the primary temperature characteristic of the crystal resonator is applied to the source of the first MOS transistor and the source of the second MOS transistor. A temperature-compensated crystal oscillator described in 1.   7. A potential based on a frequency adjustment signal input from the outside is applied to the drain of the first MOS transistor and the drain of the second MOS transistor. A temperature-compensated crystal oscillator described in 1.   The variable capacitance element has a gate electrode potential applied based on one of the first correction signal and the second correction signal, and a well electrode potential applied based on the other signal. The temperature-compensated crystal oscillator according to claim 1, wherein the temperature-compensated crystal oscillator is a type variable capacitor.