Frequency calibration system for higher order temperature compensation of a crystal oscillator

摘要

A frequency calibration system includes at least two compensation circuits (204, 206) and a comparator. The at least two compensation circuits (204, 206) are coupled to an input signal for outputting at least a first compensation signal and a second compensation signal respectively. The comparator is coupled to the first compensation signal and the second compensation signal for outputting a calibration signal, where the calibration signal is used for determining an oscillation frequency of a crystal oscillator to achieve a purpose of frequency compensation with a temperature.