Abstract:
A method of improving noise characteristics of an all-digital phase locked loop generating a feedback word representing a continuous-time oscillating signal, including a time-to-digital converter input with the continuous-time oscillating signal and a reference signal function of a reference clock, the time-to-digital converter generating a digital word representing either the ratio between the oscillating signal and the reference signal or the DCO output phase, the feedback word being a function of said digital word, comprises the step of corrupting with a dither signal at least one among the reference clock, the digital word and the oscillating signal. This method is implemented by a respective feedback circuit for an all-digital phase locked loop.