摘要 |
A method and apparatus for compensating for temperature variation in a phase locked loop (PLL) includes receiving an error signal by a controller in which the error signal representative of an instantaneous frequency difference between a reference frequency signal and an output frequency signal of a voltage controlled oscillator of the PLL, and determining when a voltage of the error signal is outside of a predetermined voltage range. When the voltage is outside the predetermined voltage range, the method includes generating a new digital compensation signal based upon a previous digital compensation signal, and converting the new digital compensation signal to be an analog compensation signal. The method further includes filtering the analog compensation signal by a filter to produce a filtered analog compensation signal, and adjusting the output frequency of the voltage controlled oscillator in accordance with the filtered analog compensation signal. |