Disclosed are a clock and data recovery circuit, method and apparatus. The circuit comprises a receiving module for receiving an analog signal; a first equalization module connected to the receiving module, the first equalization module comprising a first totalizer and a second totalizer; a first sampling module connected to an output end of the first totalizer, the first sampling module comprising a first edge sampler and a second edge sampler that are connected to the output end of the first totalizer, respectively; a second sampling module connected to an output end of the second totalizer; a data processing module connected to both the first sampling module and the second sampling module; a clock recovery module connected to the data processing module; and an output module connected to the clock recovery module. In the present application, by means of the manner, a phase can be adjusted using a bias voltage, thereby accurately recovering clock information.

Disclosed are a clock and data recovery circuit, method and apparatus. The circuit comprises a receiving module for receiving an analog signal; a first equalization module connected to the receiving module, the first equalization module comprising a first totalizer and a second totalizer; a first sampling module connected to an output end of the first totalizer, the first sampling module comprising a first edge sampler and a second edge sampler that are connected to the output end of the first totalizer, respectively; a second sampling module connected to an output end of the second totalizer; a data processing module connected to both the first sampling module and the second sampling module; a clock recovery module connected to the data processing module; and an output module connected to the clock recovery module. In the present application, by means of the manner, a phase can be adjusted using a bias voltage, thereby accurately recovering clock information.

An accurate replica oscillator-based frequency tracking loop (FTL) is provided. The replica oscillator used in the FTL can be at a lower frequency and therefore can consume much lower power compared to a main oscillator, such as an injection locked oscillator (ILO). The proposed FTL accurately sets the free running frequency of an ILO across process, voltage and temperature (PVT). Techniques are also provided to compensate the gain and offset error between the replica oscillator and the ILO.

An accurate replica oscillator-based frequency tracking loop (FTL) is provided. The replica oscillator used in the FTL can be at a lower frequency and therefore can consume much lower power compared to a main oscillator, such as an injection locked oscillator (ILO). The proposed FTL accurately sets the free running frequency of an ILO across process, voltage and temperature (PVT). Techniques are also provided to compensate the gain and offset error between the replica oscillator and the ILO.

A phase-locked loop circuit includes a voltage controlled oscillator (VCO) that generates a VCO clock in response to a voltage control signal, a divider that divides the VCO clock to output a division clock, a phase-frequency error detector that receives a reference clock and outputs a first error compensation signal, a sampler that receives the reference clock and oversamples the reference clock at a rising edge or a falling edge to output a sampling clock, a window phase error detector that receives the reference clock and outputs a second error compensation signal, a residue phase error detector that outputs a third error compensation signal, an adder that accumulates the first error compensation signal, the second error compensation signal, and the third error compensation signal to output a final error compensation signal, and a loop filter that converts and output the final error compensation signal into the voltage control signal.

An aspect relates to an apparatus including an input buffer including an input configured to receive an input voltage; a ramp voltage generator including an input coupled to an output of the input buffer; an evaluation circuit including an input coupled to an output of the ramp voltage generator, wherein the evaluation circuit includes a first resistor coupled in series with first field effect transistor (FET) between a first voltage rail and a second voltage rail; and an output buffer including an input coupled to a drain of the first FET and an output configured to generate an output voltage.

An aspect relates to an apparatus including an input buffer including an input configured to receive an input voltage; a ramp voltage generator including an input coupled to an output of the input buffer; an evaluation circuit including an input coupled to an output of the ramp voltage generator, wherein the evaluation circuit includes a first resistor coupled in series with first field effect transistor (FET) between a first voltage rail and a second voltage rail; and an output buffer including an input coupled to a drain of the first FET and an output configured to generate an output voltage.

The present invention provides a circuitry including a PLL and a CDR circuit, wherein the CDR circuit includes a phase detector, a loop filter, a SSC demodulator, a control code generator and a phase interpolator. The PLL is configured to generate a clock signal with SSC modulation and a SSC direction signal. The phase detector is configured to compare phases of an input signal and an output clock signal to generate a detection result, wherein the input signal is with SSC modulation. The loop filter is configured to filter the detection result to generate a filtered signal. The SSC demodulator is configured to receive the SSC direction signal to generate a control signal. The control code generator is configured to generate a control code according to the filtered signal and the control signal to control the phase interpolator to use the clock signal to generate the output clock signal.

The present invention provides a circuitry including a PLL and a CDR circuit, wherein the CDR circuit includes a phase detector, a loop filter, a SSC demodulator, a control code generator and a phase interpolator. The PLL is configured to generate a clock signal with SSC modulation and a SSC direction signal. The phase detector is configured to compare phases of an input signal and an output clock signal to generate a detection result, wherein the input signal is with SSC modulation. The loop filter is configured to filter the detection result to generate a filtered signal. The SSC demodulator is configured to receive the SSC direction signal to generate a control signal. The control code generator is configured to generate a control code according to the filtered signal and the control signal to control the phase interpolator to use the clock signal to generate the output clock signal.

Provided is a time-to-digital converter, comprising a phase frequency detector configured to receive a phase-locked loop input clock and a feedback clock, a ring oscillator configured to perform oscillation with multi-phase clocks of a first period, a counter array configured to count the number of oscillations in which the ring oscillator oscillates in a first period by the number of positive integers during the first pulse width, a multiplexer configured to divide the first period into a plurality of zones using edge information of the multi-phase clocks of the ring oscillator, and selects and outputs voltage information of a plurality of neighboring phase clocks included in a first zone from the plurality of zones, an analog-to-digital converter, a calibrator, and a first adder, wherein the calibrator comprises, an offset lookup table generation circuit, a gain-corrected analog-to-digital conversion output generator, and a second adder.