Adaptive filtering scheme for sampling phase relations of clock networks

摘要

An apparatus for adjusting phase relation of a plurality of clock signals in a processor. The apparatus contains a phase detection circuit that receives a plurality of clock signals and generates a first output based on a phase relation between those clock signals. A controller then adjusts the delay of the clock signals based on the first output of the phase detection circuit and a bit of a delay shift register to synchronize the clock signals within a predefined range. The controller generates a second output if the phase relation between the plurality of clock signals has changed before the adjusting of the delay of the clock signals has occurred. A noise band circuit is configured to receive the second output of the controller and adjust the predefined range in response to the receiving of the second output.