Patent ID: 8319568

Claim:
A device for compensating an oscillation frequency, comprising: a generating module, configured to send a voltage control signal to one end of a variable capacitor of an LC oscillating loop to generate oscillating signals in the LC oscillating loop; and an obtaining module, configured to obtain a variable bias voltage reflecting changes of external parameters and send the variable bias voltage to the other end of the variable capacitor to compensate changes to the oscillation frequency of oscillation signals generated in the LC oscillating loop; wherein the changes of external parameters comprise the changes of the voltage parameters of the power supply, and the obtaining module further comprises: a relevant voltage obtaining unit, configured to obtain a relevant voltage that is relevant of the voltage of the working power supply according to a voltage division circuit; and a bias voltage output unit, configured to amplify the relevant voltage and output the amplified voltage as the variable bias voltage, and send the variable bias voltage to the other end of the variable capacitor to compensate changes to the oscillation frequency of the oscillation signals generated in the LC oscillating loop, wherein the bias voltage output unit further comprises a calculation amplifier, a first resistance, and a second resistance, and the amplified voltage is inputted to a positive input end of the calculation amplifier, a negative input end of the calculation amplifier is grounded through the first resistance, an output end of the calculation amplifier is connected to the negative input end of the calculation amplifier through the second resistance to construct a negative feedback loop, and the output end of the calculation amplifier outputs the amplified voltage as the variable bias voltage.