Abstract: A duty cycle detection circuit may include a detection block configured to generate a duty detection signal by detecting a duty cycle of an input clock; and a current amount control block configured to control a current flowing through the detection block in response to the input clock, regardless of a variation in a frequency of the input clock.

Abstract: A clock and data recovery circuit includes a sampler, a skew compensation block, a pulse generator, and an injection locked oscillator. The injection locked oscillator generates a recovered clock signal, the pulse generator generates a pulse signal according to input data for controlling the injection locked oscillator, the skew compensation block compensates the input data and generate compensated data, and the sampler samples the compensated data according to the recovered clock signal.

Abstract: A delay adjusting apparatus may include at least one selective delay element electrically coupled to an electrical path between an input terminal and an output terminal of the electrical path, and the at least one selective delay element configured to add a delay factor to the electrical path in response to an enable signal. The delay adjusting apparatus may include at least one fuse circuit configured to control electrical coupling of an e-fuse, in response to a program signal, and program the enable signal.

Abstract: Described are apparatuses and methods for detecting or repairing minimum-delay errors. The apparatus may include a minimum-delay error detector (MDED) to receive a clock signal and a data path signal and to detect a minimum-delay error (MDE) in the data path based on the received data path signal and the clock signal. The MDE may be repaired by adjusting one or more regional clock buffers coupled to the MDED. Further, the apparatus may include minimum-delay path replicas (MDPRs) used for detecting and repairing MDEs during normal system operations. Other embodiments may be described and/or claimed.

Abstract: In a duty cycle error detection device, a first digital code generator is configured to generate high and low codes corresponding to a lengths of high level low level periods, respectively, of a clock signal, generate a sign signal representing the longer period between the high level period and the low level period, and output one of the high and low digital codes corresponding to the shorter period as a first digital code. A clock delay circuit is configured to generate a delay clock signal by delaying the clock signal for a time corresponding to the first digital code, and a second digital code generator is configured to generate a duty error digital code corresponding to a length from a start of the longer period of the delay clock signal to an end of the longer period of the clock signal based on the sign signal.

Abstract: A loop filter in a modified phase locked loop has a proportional path generating first output signal that is proportional to an input signal and an integral path for generating a second output signal that is an integral of the input signal. An additional functional path generates a third output signal that is a predetermined function of the input signal. The predetermined function is of the form f(s)/g(s), where f and g are polynomial functions. An adder combines the first, second, and third output signals into a common output signal.

Abstract: Provided is a time-to-digital converter. The time-to-digital converter includes several delay circuits, an adder configured to count outputs of the delay circuits, and a least significant bit (LSB) truncation circuit configured to truncate a predetermined number of LSBs from a result output by the adder. The time-to-digital converter is configured to determine a time interval between a start signal and a stop signal within one cycle of a clock having a predetermined period.

Abstract: A delay lock loop including a selection unit, a delay unit, an elimination unit, and a phase detection unit is provided. The selection unit receives a non-inverted clock signal and an inverted clock signal and generates a first clock signal and a second clock signal according to an indication signal. The delay unit includes a delay factor and delays the first clock signal according to the delay factor to generate a third clock signal. The elimination unit is coupled to the selection unit and delays the second clock signal to generate a fourth clock signal. The phase detection unit is coupled to the delay unit and the elimination unit and generates the indication signal according to a phase difference between the third and fourth clock signals. The delay unit adjusts the delay factor according to the indication signal.

Abstract: A delay lock loop is provided. A delay unit includes a delay factor and delays a first clock signal to generate a second clock signal according to the delay factor. An elimination unit delays a third clock signal to generate a fourth clock signal. A phase detection unit is coupled to the delay unit and the elimination unit and generates an indication signal according to a phase difference between the second and fourth clock signals. A control unit is coupled to the phase detection unit and the delay unit. The control unit controls the delay unit according to the indication signal to adjust the delay factor. When the delay factor is equal to an initial value, an initial time difference occurs between the first and second clock signals. A time difference between the third and fourth clock signals is equal to the initial time difference.

Abstract: Certain aspects of the present disclosure provide methods and apparatus for compensating, or at least adjusting, for capacitor leakage. One example method generally includes determining a leakage voltage corresponding to a leakage current of a capacitor in a filter for a phase-locked loop (PLL), wherein the determining comprises closing a set of switches for discontinuous sampling of the leakage voltage; based on the sampled leakage voltage, generating a sourced current approximately equal to the leakage current; and injecting the sourced current into the capacitor.

Abstract: Phase compensation in an I/O (input/output) circuit includes a triangular control contour with a simplified generation circuit. A linear control circuit can generate a digital N-bit linear count, and route the least significant M bits [(M?1):0] for linear control for fine delay mixing of a phase compensation loop and the most significant (N?M) bits [(N?1):M] for linear control for coarse control of a delay chain for the phase compensation loop. Prior to decoding the least significant M bits for fine delay mixing, the control circuit performs a bitwise XOR (exclusive OR) of bit M with each of bits [(M?1):0] to generate M linear control bits as the linear control for fine delay mixing. The M linear control bits generate a linear control count having a triangular contour, where the linear control count continuously, repeatedly counts from 0 to (2M?1) to 0.

Abstract: An embodiment of a detector includes first and second generators. The first generator is operable to receive a transition of a first signal and to generate in response to the transition a first pulse having a length that is approximately equal to a length of a detection window. And the second generator is operable to receive a second signal and to generate a second pulse having a relationship to the first pulse in response to a transition of the second signal occurring approximately during the detection window.

Abstract: A clock and data recovery circuit includes a sampler, a skew compensation block, a pulse generator, and an injection locked oscillator. The injection locked oscillator generates a recovered clock signal, the pulse generator generates a pulse signal according to input data for controlling the injection locked oscillator, the skew compensation block compensates the input data and generate compensated data, and the sampler samples the compensated data according to the recovered clock signal.

Abstract: Provided is a method and an apparatus to calibrate an output of an oscillator. The method includes calibrating the output frequency of the oscillator to be a predetermined frequency. The method also generates a differential signal corresponding to the calibrated frequency, and operates the oscillator in response to the differential signal. The oscillator is controlled by the differential signal to remove common mode noise.

Abstract: An exemplary embodiment of the present disclosure illustrates a duty cycle correction apparatus for fast adjusting internal clocks to have specific duty cycles. Firstly, a reference clock is adjusted to have one specific duty cycle in response to analog feedback clocks. Then, by using a phase detector, phases of the reference clock and one internal clock are compared to generate a phase detection signal. Next, by using a digital-analog converter, complementary signals are generated according to a phase detection signal received by the counter, and the signals are used to adjust the duty cycles of the internal clocks. When the complementary signals make the duty cycle of the internal clock equals to the specific duty cycle, codes of the complementary signals are recorded.

Abstract: Various embodiments of a clock generator are disclosed. An example system may include a functional unit, and a clock generation unit configured to adjust a frequency of an output clock signal responsive to an assertion of an enable signal from the functional unit. The clock generation unit may also be configured to halt the output clock signal responsive to a de-assertion of the enable signal by the functional unit and to restart the output clock signal responsive to a determination that a first predetermined amount of time has elapsed since the output clock signal was halted. The clock generation unit may be further configured to adjust the frequency of the output clock signal responsive to restarting the output clock signal, and to halt the output clock signal responsive to a determination that the frequency of the output clock signal is within a predetermined frequency range that includes the target frequency.

Abstract: A comparator system includes: a clock node configured to supply a clock signal; a comparator configured to compare a signal of a first input node with a signal of a second input node in synchronization with the clock signal; and a first variable capacitance coupled between the first input node and the clock node.

Abstract: A method and apparatus is provided for controlling a delay line for achieving power reduction. The device comprises a delay lock loop to provide an output signal based upon a phase difference between a reference signal and a feedback signal, said delay lock loop comprising at least one delay circuit comprising a plurality of logic gates configured to provide for substantially uniform degradation of a plurality of NAND gates in a static state.

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: In a Pulse Width Modulation power converter and control method, wherein one of the operating modes steady state or load transient is detected. For either of the two operating modes one set of PID coefficients is provided for the control law that controls the duty ratio command. In case a load transient is detected, the KP gain is selected adaptively. Operating mode detection is supported by oversampling the error signal.

Abstract: Apparatus, systems, and methods are disclosed that operate to generate a clock signal in a die in a stack and to receive the clock signal in another die in the stack. Additional apparatus, systems, and methods are disclosed.

Abstract: A system and method are present for generating a modulated waveform. A timer is configured to generate a first modulated waveform signal, and an adder module is configured to calculate a delay. The delay includes at least one of an edge fractional delay and a dead time fractional delay. A delay module is operably coupled to the timer and the adder module. The delay module is configured to delay at least one of a rising edge of the first modulated waveform signal and a falling edge of the first modulated waveform signal by the delay to generate a second modulated waveform signal that has a higher frequency resolution than a frequency resolution of the first modulated waveform signal.

Abstract: Provided is a delay locked loop (DLL) including a ring oscillator (RO) including a delay line to delay a reference clock signal and generate a delayed clock signal, wherein the RO circulates, through the delay line, a feedback clock signal corresponding to the delayed clock signal to synchronize N cycles of the feedback clock signal with a cycle of the reference clock signal (where N is an integer number equal to or larger than 2); and a first frequency divider dividing the frequency of the delayed clock signal by 1/N (where N is an integer number equal to or larger than 2) to generate an output clock signal.

Abstract: The present invention proposes a digital system and method of measuring (estimating) non-energy parameters of the signal (phase, frequency and frequency rate) received in additive mixture with Gaussian noise. The first embodiment of the measuring system consists of a PLL system tracking variable signal frequency, a block of NCO full phase computation (OFPC), a block of signal phase primary estimation (SPPE) and a first type adaptive filter filtering the signal from the output of SPPE. The second embodiment of the invention has no block SPPE, and NCO full phase is fed to the input of a second type adaptive filter. The present invention can be used in receivers of various navigation systems, such as GPS, GLONASS and GALILEO, which provide precise measurements of signal phase at different rates of frequency change, as well as systems using digital PLLs for speed measurements.

Abstract: Systems and methods associated with control of clock signals are disclosed. In one exemplary implementation, there is provided a delay-lock-loop (DLL) and/or a delay/phase detection circuit. Moreover, such circuit may comprise digital phase detection circuitry, digital delay control circuitry, analog phase detection circuitry, and analog delay control circuitry. Implementations may include configurations that prevent transition back to the unlocked state due to jitter or noise.

Abstract: A signal generating circuit comprises a signal synchronizing module and a control circuit. The signal synchronizing module includes: a first delay path for delaying a target signal to generate a first delayed target signal by utilizing a first delay amount; a second delay path for delaying the target signal to generate a second delayed target signal by utilizing a second delay amount larger than the first delay amount; and a logic module, for gating the target signal to generate a first output signal according to the first delayed target signal, or gating the target signal to generate a second output signal according to the second delayed target signal. The control circuit controls the signal synchronizing module to output one of the first output signal and the second output signal according to phase difference between the target signal and a reference signal.

Abstract: An integrated circuit includes a clock control unit configured to selectively output an external clock or a delayed clock acquired by delaying the external clock as an input clock in response to a divided clock generated by dividing the external clock, when a test mode is entered; and an internal circuit operating in response to the input clock.

Abstract: In one embodiment, a delay-locked loop (DLL) for synchronizing a phase of a periodic digital output signal with a phase of a periodic digital input signal includes a deskew element responsive to the periodic digital input signal to the DLL and the periodic digital output signal from the DLL for suppressing jitter in the periodic digital output signal by synchronizing transitions in the periodic digital output signal with transitions in the periodic digital input signal and generating a final jitter-suppressed periodic digital output signal.

Abstract: A system and method are provided for frequency multiplication jitter correction. The method accepts an analog reference signal having a first frequency, and using the analog reference signal, derives a system clock signal having a second frequency, greater than the first frequency. A PLL using a voltage controlled oscillator (VCO) is one example of a frequency multiplier. The method samples the amplitude of the analog reference signal using the system clock signal and converts the sampled analog reference signal into a digitized reference signal. In response to comparing the digitized reference signal to an ideal digitized reference signal, the phase error correction for the system clock signal is derived. The phase error correction at a first instance of time can be applied to the digitized data signal, previously converted from an analog data signal sampled at a first instance of time with the system clock signal.

Abstract: A synchronization circuit may include: a variable delay unit configured to delay a first clock signal by a first delay time set in response to a delay control signal and generate a second clock signal; a first path configured to detect a phase difference between the first clock signal and a third clock signal generated by delaying the second clock signal by a second delay time and generate a phase difference detection signal; a second path configured to generate a second phase difference detection signal in response to a phase difference between the first clock signal and a fourth clock signal; and a control unit configured to generate the delay control signal in response to the phase difference detection signal and vary an update period of the delay control signal in response to the second phase difference detection signal.

Abstract: In various embodiments, systems and methods for generating high-precision pulse-width modulation include a delay-locked loop comprising multiple delay units having time-variable delays, control logic for selecting a subset S of the multiple delay units to thereby generate a time-invariant shift amount having a precision finer than that of a system clock and circuitry for applying the shift amount to rising and falling edges of a pulse-width modulation waveform to thereby generate a high-precision pulse-width modulation waveform.

Abstract: A PLL includes an oscillator, a time-to-digital converter (TDC) and a system for the remaining functionality. The TDC measures the oscillator's phase against a reference clock. The measured phase has an integer part obtained from a modulus-K counter, and a fractional part measured by a fine TDC. The system compares the measured phase with a desired phase, and filters it to obtain a parameter that controls the oscillator frequency. The TDC may also include a synchronization block to align the fine TDC and a pulse hider to reduce the power used by the fine TDC. The system may include an integrator to calculate the integer part of the desired phase, a second integrator to calculate the fractional part, and an interpolator for an even finer fraction. A method to obtain fast lock includes using the phase error rate of change to control the oscillator frequency.

Abstract: A method and an arrangement for generating a clock signal by a phase locked loop in which the time for adjusting to a prescribed frequency and phase of a clock signal is reduced by virtue of the fact that a plurality of selection signals respectively shifted by a time difference delta t are generated from the divided clock signal. A comparison signal (capture) is generated under control by an edge of the reference clock and a comparison is started in the case of which what is selected is that selection signal shifted by delta t which exhibits with its edge the least possible time deviation from the edge of the comparison signal, and the selected selection signal is output.

Abstract: A semiconductor apparatus includes: a variable delay unit configured to delay a reference clock signal in response to a delay code and generate a data latch clock signal; a delay amount control unit configured to convert a phase of external data and a phase of the data latch clock signal into first and second codes, respectively, and generate the delay code through a calculation of the first and second codes; and a data receiver configured to latch the external data as internal data in synchronization with the data latch clock signal.

Abstract: A cross-domain enablement method is configured for providing a local clock signal to a logic-circuit device, which is operated in a delay-locked loop (DLL) domain. The logic-circuit device includes a command input and a clock input. The cross-domain enablement method comprises steps of: starting to provide the local clock signal to the clock input of the logic-circuit device by enabling a clock signal in the DLL-domain when a first command signal in a clock domain is activated; and, providing a second command signal in the DLL-domain to the command input of the logic-circuit device. The second command signal in the DLL-domain is activated later than the first command signal in the clock domain.

Abstract: A semiconductor apparatus includes: a clock receiving unit configured to receive an external clock signal and output the received clock signal as a reference clock signal; a delay locked loop (DLL) configured to delay the reference clock signal by a variable delay amount and generate a data latch clock signal; a data receiving unit configured to receive external data in synchronization with the data latch clock signal and output the received data as internal data; and a determination unit configured to detect a phase difference between the reference clock signal and the data latch clock signal and generate a determination signal, when the DLL is locked.

Abstract: An oscillator may output phased signals to a phase interpolator which is to generate an adjustable output clock signal having a phase offset relative to at least one of the phased signals received from the oscillator. A divider may then divide the frequency of the output signal generated by the phase interpolator by an integer factor.

Abstract: A differential amplifier may be configured to have a duty cycle and/or gain that is adjustable, such as by adjusting the switch points of circuitry in the differential amplifier. The differential amplifier may alternatively or additionally have a hysteresis function by, for example, using a signal feedback from the output of the amplifier to adjust the switch points of circuitry in the differential amplifier. The differential amplifier may be used for a variety of purposes, such as in an input buffer or delay line, either of which may be used, for example, in a clock generator circuit.

Abstract: A digital phase locked loop has a digital controlled oscillator, a phase comparator comparing the output signal of the digital controlled oscillator, or a signal derived therefrom, with a reference signal to produce a phase error signal. A loop filter produces a control signal for the digital controlled oscillator from an output of the phase comparator the loop filter. The loop filter has a proportional part producing a proportional component of the control signal, an integral part producing an integral component of the control signal, and an adder receiving the respective proportional and integral components at first and second inputs thereof to produce the control signal. The integral part includes a delayed feedback loop normally configured to accept the integral component at an input thereof. A first switch replaces the integral component at the input of the delayed feedback loop by the control signal in response to an activation signal.

Abstract: A method and apparatus for synchronizing a delay line to a reference clock. A delay line receives a clock input signal based on a reference clock and outputs a delay edge signal according to a control signal. An injector receives a first edge of the reference clock and in response to a first trigger, sends the clock input signal to the delay line. A synchronizer determines that the first edge has passed through the delay line, and in response, sends the injector a second trigger to send a second edge of the clock input signal to the delay line. An edge detector compares the timing of the first edge of the delay edge signal to a timing of the first edge of the reference edge signal. A control signal is sent to the delay line to decrease or increase the delay setting of the delay line based on the comparison.

Abstract: A clock generation circuit comprises an internal clock signal source providing an internal clock signal and a synchronization device for synchronization the internal clock signal with a reference clock signal provided externally from the clock generation circuit. The synchronization device comprises n delay locked loop circuits, n being an integer greater than 1, each delay locked loop circuit having a clock input for receiving the internal clock signal and a clock output for providing an output clock signal with an individual phase shift that is adjustable. The synchronization device further comprises a multiplexer having n inputs and an output wherein each of the n inputs is connected to an output of one of the n delay locked loops and a control circuit.

Abstract: A variable frequency clock generator. In aspects, a clock generator includes a droop detector circuit configured to monitor a voltage supply to an integrated circuit. If the supply voltage falls below a specific threshold, a droop voltage flag may be set such that a frequency-locked loop is triggered into a droop voltage mode for handling the voltage droop at the supply voltage. In response, a current control signal that is input to an oscillator that generates a system clock signal is reduced by sinking current away from the current control signal to the oscillator. This results in an immediate reduction on the system clock frequency. Such a state remains until the voltage droop has dissipated when the current path is removed for sinking some of the current.

Abstract: A DLL circuit apparatus and a DLL locking method are provided. A control signal voltage value corresponding to a DLL locking state is stored, and a DLL unlocking state is detected when a change in control signal voltage value or a phase difference of clock signals occurs. When the DLL unlocking occurs, the DLL is locked again using the stored control signal voltage value. Accordingly, DLL unlocking from DLL locking state is quickly detected, and a fast DLL locking time occurs.

Abstract: A system and method are provided of performing background corrections for an interleaving analog-to-digital converter (ADC). An analog input signal s1(t) is accepted having a first frequency f1 and a bandwidth (BW). The method generates a clock at frequency fs, and creates 2 sample clocks with evenly spaced phases, each having a sample clock frequency of fs/2. The method also generates a first tone signal s2(t) having a predetermined second frequency f2 outside BW. The analog input signal and the first tone signal are combined, creating a combination signal, which is sampled using the sample clocks, creating 2 digital sample signals per clock period 1/fs. The 2 digital sample signals are interleaved, creating an interleaved signal. Corrections are applied that minimize errors in the interleaved signal, to obtain a corrected digital output. Errors are determined at an alias frequency f3, associated with the second frequency f2, to obtain correction information.

Abstract: A system and method are provided for frequency multiplication jitter correction. The method accepts an analog reference signal having a first frequency, and using the analog reference signal, derives a system clock signal having a second frequency, greater than the first frequency. A PLL using a voltage controlled oscillator (VCO) is one example of a frequency multiplier. The method samples the amplitude of the analog reference signal using the system clock signal and converts the sampled analog reference signal into a digitized reference signal. In response to comparing the digitized reference signal to an ideal digitized reference signal, the phase error correction for the system clock signal is derived. The phase error correction at a first instance of time can be applied to the digitized data signal, previously converted from an analog data signal sampled at a first instance of time with the system clock signal.

Abstract: A phase determination circuit includes a first phase comparison unit, a flag generation unit and a locking detector. The first phase comparison unit compares phases of a reference clock signal and a feedback clock signal and generates a first phase comparison signal. The flag generation unit generates a flag signal based on phases of the reference clock signal and a clock signal, and the first phase comparison signal. The locking detector prevents generation of a locking signal based on the first phase comparison signal.

Abstract: Systems and methods for generating a thermometer sigma delta encoded frequency control word for controlling a digitally controlled oscillator in accordance with embodiments of the invention are disclosed. In one embodiment, an all digital phase locked loop for generating an output clock signal includes a thermometer pulse coder configured to generate a frequency control word (FCW) that includes thermometer coded signals and a pulse modulated dither signal, and transmit the pulse modulated dither signal over a selected FCW signal line and transmit the thermometer coded signals over other FCW signal lines, and a digitally controlled oscillator to receive a FCW comprising a combined thermometer and pulse modulated signal and generate an output clock signal.

Abstract: There is provided a clock generating apparatus for generating a recovered clock by recovering a clock from an edge of a received signal, including a recovered clock generating section that generates the recovered clock, a multi-strobe generating section that generates a plurality of strobes with different phases, in accordance with a pulse of the recovered clock, a detecting section that detects a position of an edge of the received signal relative to the strobes, by referring to values of the received signal obtained at respective timings of the strobes, and an adjusting section that adjusts a phase of the recovered clock, in accordance with the position of the edge of the received signal.

Abstract: Representative implementations of devices and techniques provide a multi-bit binary representation of a phase difference between two signals. The multi-bit binary representation may include information regarding a sign of the phase difference and a magnitude of the phase difference.

Abstract: A delay-locked loop (DLL) operation mode control circuit and corresponding method are provided in which one of the output values from a display driver IC (DDI) is detected to switch a DLL block to standby mode. In examples, a CLKP/N frequency and CLKP/N common terminal voltage status are used to switch mode. Accordingly, since inoperable frequency domains otherwise present in a normal mode interval of the DLL block is included into standby mode, more stable operation of the DLL circuit is provided.