A short-reach data link receiver includes an edge detector configured to generate a pulse on an edge of a data input, a first clock-data recovery path coupled to an output of the edge detector for recovering a clock and data from the output of the edge detector, a second clock-data recovery path coupled to the output of the edge detector for recovering the clock and data from the output of the edge detector, and a controller configured to alternate between the first and second clock-data recovery paths to recover the clock and data using one of the paths while calibrating the other path. The controller may swap the paths whenever calibration of one path is completed. That may include beginning calibration of the next path immediately after swapping of the paths. Alternatively, power consumption may be reduced by delaying calibration of the next path after swapping of the paths.

A circuit includes a phase and frequency detector circuit to generate a first phase detect signal indicative of whether a polarity of a first clock is the same as a polarity of a second clock upon occurrence of an edge of a data signal. The second clock being 90 degrees out of phase with respect to the first clock. A lock detect circuit determines, based on the first phase detect signal, that a third clock is one of frequency and phase locked to the data signal, frequency and quadrature locked to the data signal, and not frequency locked to the data signal.

A receiver device implements enhanced data reception with edge-based clock and data recovery such as with a flash analog-to-digital converter architecture. In an example embodiment, the device implements a first phase adjustment control loop, with for example, a bang-bang phase detector, that detects data transitions for adjusting sampling at an optimal edge time with an edge sampler by adjusting a phase of an edge clock of the sampler. This loop may further adjust sampling in received data intervals for optimal data reception by adjusting the phase of a data clock of a data sampler such a flash ADC. The device may also implement a second phase adjustment control loop with, for example, a baud-rate phase detector, that detects data intervals for further adjusting sampling at an optimal data time with the data sampler.

A data receiver circuit may include: a delay circuit suitable for delaying first and second strobe signals and generating delayed first and second strobe signals; a first receiver circuit suitable for sampling data in synchronization with the delayed first strobe signal; a second receiver circuit suitable for sampling the data in synchronization with the delayed second strobe signal; an enable signal generation circuit suitable for generating an enable signal indicating whether the data transitioned; a transition level generation circuit suitable for generating a transition level signal indicating a transition direction of the data; a phase shift circuit suitable for shifting the phase of the delayed first strobe signal by a set degree and generating a shifted first strobe signal; a sampling circuit suitable for sampling the data in synchronization with the shifted first strobe signal and generating a sampling result; and a control logic suitable for changing a delay value of the delay circuit in response to the transition level signal and the sampling result of the sampling circuit, when the enable signal is activated.

A receiver includes: an A/D converter that performs an analog digital conversion of an input signal; an equalizer that equalizes an output from the A/D converter, eliminates inter code interference and obtains a data output; a timing recovery part that generates a recovery clock from the data output of the equalizer; a detector that detects the timing when an input signal varies from a no-signal state and has reached a predetermined threshold; and an initial phase setting part that sets as the initial phase of the recovery clock by the timing recovery part, a timing when the predetermined time has elapsed after the timing detected by the detector.

A method and system that provides for execution of a first calibration sequence, such as upon initialization of a system, to establish an operation value, which utilizes an algorithm intended to be exhaustive, and executing a second calibration sequence from time to time, to measure drift in the parameter, and to update the operation value in response to the measured drift. The second calibration sequence utilizes less resources of the communication channel than does the first calibration sequence. In one embodiment, the first calibration sequence for measurement and convergence on the operation value utilizes long calibration patterns, such as codes that are greater than 30 bytes, or pseudorandom bit sequences having lengths of 2.sup.N1 bits, where N is equal to or greater than 7, while the second calibration sequence utilizes short calibration patterns, such as fixed codes less than 16 bytes, and for example as short as 2 bytes long.

Some embodiments include apparatus having sampling circuitry, a first circuit path, a second circuit path, and a digitally controlled oscillator (DCO). The sampling circuit samples an input signal and provide data information and phase error information based on the input signal. A first circuit path provides proportional control information based on the data information and phase error information. A second circuit path provides integral control information based on the data information and phase error information. The first circuit path operates at a frequency higher than the second circuit path. The DCO generates a clock signal and controls the timing of the clock signal based on the integral control information and the proportional control information.

A timing lock identification method is provided according to an embodiment of the disclosure. The method includes: generating one or more first phase adjustment pulses and one or more second phase adjustment pulses by a timing recovery circuit, where the one or more first phase adjustment pulses are configured to increase a phase of an output signal of an oscillator, and the one or more second phase adjustment pulses are configured to decrease the phase of the output signal; and obtaining a difference value between the number of the one or more first phase adjustment pulses and the number of the one or more second phase adjustment pulses in a detection window and determining whether the timing recovery circuit reaches a locking state of timing recovery according to the difference value. Furthermore, a signal receiving circuit is provided according to an embodiment of the disclosure.

A storage device and a storage system including the same are provided. The storage device includes a reference clock pin configured to receive a reference clock signal from a host, a reference clock frequency determination circuitry configured to determine a reference clock frequency from the reference clock signal received through the reference clock pin, and a device controller circuitry configured to perform a high speed mode link startup between the host and the storage device according to the reference clock frequency.

The invention relates to a method and timing recovery circuit for recovering a sampling clock from a serial data stream encoded using Pulse-Amplitude-Modulation, comprising: applying a filter pattern decoder to detected symbol sequence at more than two adjacent data symbols, particularly to the detected symbol patterns of four adjacent samples {circle around (y)}(k2), {circle around (y)}(k1), {circle around (y)}(k), {circle around (y)}(k+1), and calculating an estimated phase error e(k).