US Patent 10355699 Hitless re-arrangements in coupled digital phase-locked loops

An apparatus comprising an accumulator circuit and an offset register. The accumulator circuit may be configured to (a) receive a plurality of frequency offset values from a plurality of sourcing DPLLs and (b) generate a current combined offset value in response to a sum of the frequency offset values. The offset register may be configured to (a) store an offset value corresponding to the current combined offset value in a first mode and (b) store an offset value corresponding to an updated offset value in a second mode. The updated offset value may comprise a difference between the offset value stored in the offset register and the current combined offset value. The offset value may be presented to a receiving DPLL during a re-arrangement of the sourcing DPLLs. Presenting the offset value may reduce a phase transient caused by the re-arrangement.