Abstract: 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.

Abstract: An apparatus includes a plurality of digital phase-locked loops and a time slotted bus. The time slotted bus is configured to couple the plurality of digital phase-locked loops. The plurality of digital phase-locked loops may be configured to exchange parameters between two or more of the plurality of digital phase-locked loops using one or more time slots of the time slotted bus.

Abstract: An apparatus includes a plurality of digital phase-locked loops and a time slotted bus. The time slotted bus is configured to couple the plurality of digital phase-locked loops. The plurality of digital phase-locked loops may be configured to exchange parameters between two or more of the plurality of digital phase-locked loops using one or more time slots of the time slotted bus.

Abstract: An apparatus includes a plurality of digital phase-locked loops and a time slotted bus. The time slotted bus is configured to couple the plurality of digital phase-locked loops. The plurality of digital phase-locked loops may be configured to exchange parameters between two or more of the plurality of digital phase-locked loops using one or more time slots of the time slotted bus.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: An apparatus includes a plurality of digital phase-locked loops and a time slotted bus. The time slotted bus is configured to couple the plurality of digital phase-locked loops. The plurality of digital phase-locked loops may be configured to exchange parameters between two or more of the plurality of digital phase-locked loops using one or more time slots of the time slotted bus.

Abstract: A Synchronous Ethernet (SyncE) network device includes a pair of phase-locked loops including a first phase-locked loop responsive to a SyncE input clock and a second phase-locked loop coupled to the first phase-locked loop. The second phase-locked loop is configured to be simultaneously lockable to both the SyncE input clock via the first phase-locked loop and an IEEE 1588 packet stream, during a locked mode of operation, and also lockable to the SyncE input clock during a holdover mode of operation which is triggered in response to a failure of the IEEE 1588 packet stream.

Abstract: The present invention is a method to rapidly lock a type II phase locked loop (PLL) after a frequency jump without degrading the output signal much. The method to decrease the settling time and improve the quality of the output clock during the settling disclosed herein comprises of the following broad steps: Estimate new frequency offset with a separate circuit outside the PLL loop to measure the frequency of the input signal accurately. Ramp integrator to the new frequency offset. Do phase build out or phase pull-in. The remaining phase offset is build out when no edge to edge alignment is required. Otherwise, the remaining phase offset is pulled in while the integrator in the PLL's loop filter is disabled. Reduce the PLL bandwidth and/or lower damping to let the PLL settle. Switch the PLL to final bandwidth and damping required by the application.

Abstract: A multimode clock recovery circuit for providing constant bit rate services in a cell relay network has an embedded digital phase locked loop including an input circuit capable of generating a phase signal from at least two types of input signal. The phase signal controlling the output of the phase locked loop generates clock signals for the constant bit rate services.

Abstract: A multimode clock recovery circuit for providing constant bit rate services in a cell relay network has an embedded digital phase locked loop including an input circuit capable of generating a phase signal from at least two types of input signal. The phase signal controlling the output of the phase locked loop generates clock signals for the constant bit rate services.