Temperature compensated oscillation controller and temperature compensated crystal oscillator including the same

A temperature compensated crystal oscillator comprising:

• a temperature compensated oscillation controller including first through fourth terminals;
• a thermistor connected to the first and second terminals;
• and
• a crystal resonator connected to the third and fourth terminals,
• wherein the temperature compensated oscillation controller comprises:
• a temperature compensation circuit configured to provide a reference voltage through the first terminal and to receive an input voltage through the second terminal;
• and
• an oscillation circuit connected to the third and fourth terminals and configured to output a clock signal in response to an oscillation signal of the crystal resonator,
• wherein the temperature compensation circuit is configured to convert the input voltage into a temperature code by performing a voltage controlled oscillator-based sensing operation and to adjust a capacitance of the third and fourth terminals using the temperature code.

A user system comprising:

• a first plurality of configuration elements;
• a second plurality of configuration elements;
• a first temperature compensated crystal oscillator comprising a switched capacitor and configured to provide a clock signal to the first plurality of configuration elements;
• and
• a second temperature compensated crystal oscillator comprising an external resistor and configured to provide the clock signal to the second plurality of configuration elements,
• wherein each of the first and second temperature compensated crystal oscillators further comprises:
• a temperature compensated oscillation controller including first through fourth terminals;
• a thermistor connected to the first and second terminals;
• and
• a crystal resonator connected to the third and fourth terminals,
• wherein the temperature compensated oscillation controller comprises:
• a temperature compensation circuit configured to provide a reference voltage through the first terminal and to receive an input voltage including temperature information through the second terminal;
• and
• an oscillation circuit connected to the third and fourth terminals and configured to output the clock signal in response to an oscillation signal of the crystal resonator,
• wherein the temperature compensation circuit is configured perform a voltage controlled oscillator-based sensing operation to convert the input voltage into a temperature code and to adjust a frequency of the clock signal using the temperature code.