Abstract: Semiconductor devices for synchronizing networks are described. A semiconductor device can include an analog phase-lock loop (APLL) configured to output a first signal. The semiconductor device can further include a first digital phase-lock loop (DPLL) configured to output a second signal. The semiconductor device can further include a second DPLL configured to output a third signal. A combination of the first signal and the second signal can be used to generate a first output clock signal. A difference resulting from a subtraction of the second signal from the third signal can be used to generate a second output clock signal.

Abstract: A method of operating a clock circuit can include transmitting a clock signal from a transmitter of a first system to a receiver of a second system, where a first repeating edge of a clock cycle of the clock signal repeats at a predetermined constant frequency within the clock signal to synchronize operations of the second system, and varying, by the first system, a second edge within the clock cycle of the clock signal to transmit a data transmission within the clock signal.

Abstract: A method of synchronizing operations between integrated circuits can include transmitting a first clock signal from a first transmitter associated with a first integrated circuit of a first system, to a receiver associated with a second integrated circuit of a second system, receiving a second clock signal from a second transmitter associated with a third integrated circuit of the second system, receiving at the first system a first phase difference determined by the second system, wherein the first phase difference is determined between the first clock signal at the second system and the second clock signal at the second system, determining a second phase difference at the first system, wherein the second phase difference is determined between the first clock signal at the first system and the second clock signal at the first system, and determining a difference between the first phase difference and the second phase difference.

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 digital phase locked loop (DPLL) for providing clock synchronization in backplane bus systems has a loop filter with selectable high and low bandwidth modes. The DPLL is thus capable of respectively attenuating or tracking jitter from an input reference clock.

Abstract: A digital phase locked loop (DPLL) for providing clock synchronization in backplane bus systems has a loop filter with selectable high and low bandwidth modes. The DPLL is thus capable of respectively attenuating or tracking jitter from an input reference clock.