Abstract:
A digital phase locked loop operates with a time-to-digital converter and an a-priori-probability-phase-estimation component or estimator component that estimates the un-quantized phase associated with a quantization output of the time-to-digital converter. The time-to-digital converter generates a quantized value as the quantization output from a local oscillator signal of a local oscillator and a reference signal of a reference clock. The estimation component estimates a phase value from the quantized values as a function of a-priori data related to the time-to-digital converter and boundaries of the quantized value.
Abstract:
A circuit is configured to reduce a noise component of a measured phase signal. The circuit includes an input for a phase signal of an oscillator and an error signal estimator configured to determine parity information and an estimated error amplitude in the phase signal based on the parity information. The circuit further includes a combiner configured to provide the measured phase signal with the reduced noise component based on a combination of the phase signal and the estimated error amplitude.
Abstract:
Aspects of a digital phase-lock loop (DPLL) with an adjustable delay between an output clock and a reference clock in accordance with phase noise compensation are generally described herein. An apparatus may include processing circuitry configured to, in a first mode, identify a delay element of a plurality of delay elements based on an associated delay value, and set an initial phase difference value to a phase difference value associated with the identified delay element. The processor circuitry may be further configured to, in a second mode, in a second mode, initialize the DPLL using the initial phase difference value, determine a phase error between a reference clock and a feedback clock based on the initial phase difference value, adjust an output clock signal based on the phase error.
Abstract:
Systems, methods, and circuitries for synchronizing a first phase locked loop (PLL) with a second PLL are provided. In one example a PLL system includes a first PLL configured to generate a first signal; a second PLL configured to generate a second signal; and phase calculation circuitry. The phase calculation circuitry is configured to calculate a phase of the first signal at a given time; and provide the calculated phase to the second PLL for use by the second PLL in synchronizing a phase of the second with the phase of the first signal.
Abstract:
A time-to-digital converter is provided. The time-to-digital converter includes a delay circuit configured to iteratively delay a reference signal for generating a plurality of delayed reference signals. Further, the time-to-digital converter includes a plurality of sample circuits each configured to sample an oscillation signal based on one of the plurality of delayed reference signals. The time-to-digital converter additionally includes a control circuit configured to de-activate at least one of the plurality of sample circuits based on a predicted value of the phase of the oscillation signal.
Abstract:
A Digital Phase Locked Loop (DPLL), including a Time-to-Digital Converter (TDC) configured generate quantized phase values of a controlled oscillator signal; and a frequency estimation circuit configured to receive the quantized phase values, determine wraparound phase of the quantized phase values, and estimate a frequency based on the quantized phase values and the wraparound phase.
Abstract:
A time-to-digital converter is provided. The time-to-digital converter includes a delay circuit configured to iteratively delay a reference signal for generating a plurality of delayed reference signals. Further, the time-to-digital converter includes a plurality of sample circuits each configured to sample an oscillation signal based on one of the plurality of delayed reference signals. The time-to-digital converter additionally includes a control circuit configured to de-activate at least one of the plurality of sample circuits based on a predicted value of the phase of the oscillation signal.
Abstract:
A Digital Phase Locked Loop (DPLL), including a Time-to-Digital Converter (TDC) configured generate quantized phase values of a controlled oscillator signal; and a frequency estimation circuit configured to receive the quantized phase values, determine wraparound phase of the quantized phase values, and estimate a frequency based on the quantized phase values and the wraparound phase.
Abstract:
A digital phase lock loop (DPLL) device or system can operate to analyze and estimate a deterministic jitter in the digital domain, while correcting for it in the analog domain. A reference oscillator can provide an analog reference signal to the DPLL via a reference path. A shaper of the reference path can process the analog reference signal and provide a digital signal to a doubler component that doubles the frequency for a digital reference signal. The doubler component itself can add deterministic jitter to the noise of the digital reference signal it provides to the DPLL. An estimation of the DPLL performs various calibration processes to determine the deterministic jitter in the digital domain and provide an analog bias signal to the signal shaper component to correct for the deterministic jitter, keeping it at around zero.