A frequency synthesizer comprising a phase locked loop, the phase locked loop comprising: means for generating an alternating-current output signal having a frequency which depends on an applied control voltage; active filtering means (34,C31,C32,R31) for providing a control voltage to said means for generating an alternating-current output signal, said control voltage reflecting determined phase differences between a frequency divided output signal of said means for generating an alternating-current output signal and a reference signal, wherein said active means comprise at least one capacitor (C31,C32); means for detecting frequency deviations between said frequency divided output signal of said means for generating an alternating-current output signal and a reference signal, wherein a resolution employed for detecting said frequency deviations is lower than a resolution employed for determining said phase differences; characterized by means for adding a direct-current voltage shift at an output of said active filtering means for providing a control voltage to said control voltage provided by said active means for providing a control voltage, in response to detecting frequency deviation by said means for detecting frequency deviations, for reducing dielectric absorption of said at least one capacitor; wherein said means for generating an alternating-current output signal, said active means for providing a control voltage, including said at least one capacitor, said means for detecting frequency deviations and said means for adding a direct-current voltage shift to a control voltage are integrated in an integrated circuit. means for generating an alternating-current output signal having a frequency which depends on an applied control voltage; active filtering means (34,C31,C32,R31) for providing a control voltage to said means for generating an alternating-current output signal, said control voltage reflecting determined phase differences between a frequency divided output signal of said means for generating an alternating-current output signal and a reference signal, wherein said active means comprise at least one capacitor (C31,C32); means for detecting frequency deviations between said frequency divided output signal of said means for generating an alternating-current output signal and a reference signal, wherein a resolution employed for detecting said frequency deviations is lower than a resolution employed for determining said phase differences; characterized by means for adding a direct-current voltage shift at an output of said active filtering means for providing a control voltage to said control voltage provided by said active means for providing a control voltage, in response to detecting frequency deviation by said means for detecting frequency deviations, for reducing dielectric absorption of said at least one capacitor; wherein said means for generating an alternating-current output signal, said active means for providing a control voltage, including said at least one capacitor, said means for detecting frequency deviations and said means for adding a direct-current voltage shift to a control voltage are integrated in an integrated circuit.