A clock recovery circuit includes a clock detector configured to receive a serial data stream from a remote device over a reverse channel, wherein the serial data stream includes clock reference data, reverse channel data, or a combination of the clock reference data and the reverse channel data, and the clock detector configured to output a clock detect signal in response to detecting the clock reference data in the serial data stream; a phase lock loop including a first detector configured to receive the serial data stream and to detect phase and frequency; and a controller configured to receive the clock detect signal and to selectively enable the first detector based on the clock detect signal.

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.N−1 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.

An apparatus includes a receiver buffer, a phase compensation circuit, a data sampler circuit, and an error sampler circuit. The receiver buffer may generate an equalized signal on a signal node using an input signal received via a channel. The phase compensation circuit may, in response to an initiation of a training mode, replace the equalized signal on the signal node with a reference signal. The data sampler circuit may sample, using a data clock signal, the reference signal to generate a plurality of data samples. The error sampler circuit may sample, using an error clock signal, the reference signal to generate a plurality of errors samples. The phase compensation circuit may also adjust a phase difference between the data clock signal and the error clock signal using at least some of the plurality of data samples and at least some of the plurality of error samples.

A display device including: a timing controller outputting a reference clock signal and a data packet, wherein the data packet includes a clock signal embedded in a data signal; a clock and data recovery (CDR) circuit receiving the reference clock signal and the data packet; and a display panel displaying an image based on the data packet, wherein, when the CDR circuit receives the reference clock signal, a frequency band of the reference clock signal is detected using a first internal clock signal, a parameter associated with jitter characteristics of the clock and data recovery circuit is adjusted according to the detected frequency band, and a second internal clock signal is output by adjusting a frequency of the first internal clock signal, and when the CDR circuit receives the data packet, the data signal and a clock signal synchronized with the data signal are recovered from the data packet.

According to one embodiment, an interface system includes a receiver, a first clock generator, a second clock generator, and a sampling circuit. The receiver is configured to receive a first clock and serial data from a host. The first clock generator includes a first voltage controlled oscillator (VCO) and is configured to generate a second clock on the basis of the first clock. The second clock generator includes a second voltage controlled oscillator (VCO) and is configured to generate a third clock on the basis of the serial data. The sampling circuit is configured to sample reception data on the basis of the third clock and the serial data.

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.

Embodiments are disclosed for facilitating an end-to-end link channel with one or more lookup tables for equalization. An example system includes a first transceiver and a second transceiver. The first transceiver includes a clock data recovery (CDR) circuit configured to receive communication data from a switch and to manage a lookup table associated with equalization of the communication data. The first transceiver also includes a first driver circuit communicatively coupled to the CDR circuit and configured to generate an electrical signal associated with the communication data. The second transceiver includes a second driver circuit, communicatively coupled to the first transceiver, that is configured to receive the electrical signal from the first transceiver and to modulate a laser source based on the electrical signal to generate an optical signal via the laser source.

Some examples described herein provide an integrated circuit comprising an auxiliary clock and data recovery (CDR) circuitry. The CDR circuitry is configured to oversample an incoming data signal and generate a locked clock signal. The auxiliary CDR circuitry may comprise a phase-locked loop (PLL) configured to receive the incoming data signal and generate the locked clock signal. The PLL may comprise a phase detector (PD) configured to receive the incoming data signal and capture a number of samples of the incoming data signal in response to a number of adjacent clock signals and minimum data transition thresholds implemented by an intersymbol interference (ISI) filter, the minimum data transition thresholds identifying minimum data transitions in the incoming data signal.

A clock and data recovery circuit includes a phase detector that outputs phase characteristic data based on a digital data signal and an adjustment circuit that adjusts phase characteristic data. The clock and data recovery circuit sets an adjustment value in an adjustment circuit by calculating an adjustment value of phase characteristic data using a monitor circuit while changing a phase of a reference clock signal to be adjusted in a phase interpolation circuit based on offset data output from an offset output circuit in a training period before communication starts.

The present disclosure discloses a clock and data recovery circuit. The clock and data recovery circuit may include a clock recovery unit configured to output a recovery clock signal by operating a first time-to-digital conversion circuit or a second time-to-digital conversion circuit depending on a phase difference between a clock of an input signal and the recovery clock signal, and a data recovery unit configured to sample data from the input signal and output recovery data.