Abstract: One embodiment of the present invention provides a phase-locked loop (PLL) for synthesizing a fractional frequency. The PLL can include a 1/N frequency divider, a voltage-controlled oscillator (VCO), a programmable phase mixer, and a phase detector. The programmable phase mixer can be coupled between an output of the VCO and an input of the frequency divider, wherein the programmable phase mixer is configured to receive the output clock signal from the VCO and generate a first clock signal of frequency f1 by varying a phase of the output clock signal. The frequency divider is configured to receive the first clock signal from the programmable phase mixer and generate a second clock signal of frequency f2=f1/N. The phase detector can receive a reference clock signal and the second clock signal as inputs, and the phase detector's output can be used to generate the control voltage for the VCO.

Abstract: A semiconductor apparatus includes a first structural body including a first temperature voltage generation unit configured to generate first and second temperature voltages which have different voltage level variations according to a temperature variation, in response to a temperature measurement command, and a first temperature information determination unit configured to generate first temperature information depending on a difference between levels of the first and second temperature voltages; and a second structural body including a second temperature voltage generation unit configured to generate a third temperature voltage and a fourth temperature voltage which have different voltage level variations according to a temperature variation, when a predetermined time elapses after the first and second temperature voltages are generated from the first structural body, and a second temperature information determination unit configured to generate second temperature information depending on a difference betwe

Abstract: An internal clock signal generation circuit is capable of controlling a unit delay time depending on a frequency of an external clock signal. The internal clock signal generation circuit includes an internal clock signal generation unit configured to generate an internal clock signal corresponding to a plurality of unit delay cells enabled in response to a control signal, and a unit delay time control unit configured to detect a frequency of an external clock signal and control a unit delay time of each of the plurality of unit delay cells.

Abstract: Duty cycle correction systems and methods of adjusting duty cycles are provided. One such duty cycle correction system includes a duty cycle adjustor and a variable delay line coupled to the duty cycle adjustor. First and second phase detectors have first inputs coupled to the duty cycle adjustor through an inverter and second inputs coupled to the variable delay line. The phase detectors cause the delay line to align rising or falling edges of signals at the output of the delay line with rising or falling edges, respectively, of signals at the output of the inverter. The controller simultaneously causes the duty cycle adjustor to adjust the duty cycle of the output clock signal until the rising and falling edges of signals at the output of the delay line are aligned with rising and falling edges, respectively, of signals at the output of the inverter.

Abstract: A method for compensator for comparator offset is provided. A first propagation delay for a first signal traversing a comparator to a first output terminal of the comparator and a second propagation delay for a second signal traversing the comparator to a second output terminal of the comparator are measured. The first and second propagation delays are then compared to generate a comparison result, and the comparator is adjusted to compensate for an input voltage offset based at least in part on the comparison result.

Abstract: A synchronizing circuit compatible with a quad switching scheme in a digital-to-analog converter (DAC) to synchronize turning on or off of switches for steering current to a differential output. The synchronizing circuit receives signals from a decoder and synchronizes control signals to the switches by a clock signal. In one embodiment, the synchronizing circuit includes a predictor circuit and a latch circuit. The latch circuit may include four sets of cross-coupled inverters where a set of cross-coupled inverters are activated at a time. By using the synchronizing circuit in conjunction with the quad switching scheme, linearity of analog output from the DAC can be improved and data dependent noise in the analog output can be removed or reduced.

Abstract: A delay locked loop includes a pulse generator, a delay unit, a phase detector and a control unit. The pulse generator generates a pulse signal and a determination signal according to an input clock signal. The delay unit delays the pulse signal according to a digital control signal to generate a delayed pulse signal. The phase detector detects a time delay of the delayed pulse signal according to the determination signal to generate a detection result. The control unit generates a digital control signal according to the detection result to control the delayed pulse signal by a delay amount.

Abstract: Disclosed is a multi-phase clock signal generation circuit including two circuit blocks, each of which includes a cross-coupled structure and two delay units, and the delay units are adjustable. The circuit block MD1 includes two NMOS transistors, two PMOS transistors, and two delay units. The circuit block MD2 may include two NMOS transistors, two PMOS transistors, and two delay units. The circuit can generate clock signals with respective phases whose relationship is relatively independent of integration process, operating voltage and temperature, thereby allowing guaranteed efficiency for a multi-phase charge pump.

Abstract: Systems and methods for generating control signal in radiation detector systems are provided. One system includes a scheduling architecture having at least one anode channel connected to a detector of the radiation detector system. The anode channel includes a charge sensitive amplifier and a signal shaper, wherein the anode channel is configured to generate at least one control signal to control data acquisition by the detector. The scheduling architecture also includes at least one shaper timer configured having a time constant to define timing for the generation of the control signal without using a clock.

Abstract: A delay locked loop includes a delay pulse generation unit, a coding unit, and a delay line. The delay pulse generation unit is configured to generate a delay pulse having a certain width. The coding unit is configured to code the delay pulse and output a code value. The delay line is configured to delay an input clock by the code value, and generate a delayed locked clock. The delay pulse has a logic high level state during a third period equivalent to a difference between a first period, which corresponds to an integer multiple of the input clock, and a second period, which is a certain replica delay period.

Abstract: Phase interpolator and a delay circuit for the phase interpolator. The phase interpolator includes a variable delay circuit to rotate phase of an input clock to generate a phase rotated signal. The phase interpolator also includes a delay locked loop coupled to the variable delay circuit to generate a plurality of phase shifted outputs. The delay locked loop includes a plurality of delay elements. Each delay element includes a multiplexer and a delay cell coupled to the multiplexer. The multiplexer is configurable using a first control signal to output one of the phase rotated signal and a phase shifted output of the plurality of phase shifted outputs. The delay cell delays one of the phase rotated signal and the phase shifted output to generate another phase shifted output of the plurality of phase shifted outputs.

Abstract: A timing generator that outputs a timing signal obtained by delaying an input signal, comprising first and second period delay sections that each output a rate signal obtained by delaying the input signal by a delay amount corresponding to an integer multiple of a period of an operation clock supplied thereto; a first high-accuracy delay section that outputs the timing signal obtained by delaying a signal input thereto by a delay amount that is less than the period of the operation clock; and a mode switching section that switches between a low-speed mode, in which the rate signal output by the first period delay section is input to the first high-accuracy delay section, and a high-speed mode, in which a signal obtained by interleaving the rate signals output by the first period delay section and the second period delay section is input to the first high-accuracy delay section.

Abstract: In one embodiment, multiple (serializer/deserializer) SERDES channels are aligned by selectively slipping one or more of the incoming serial data streams one bit at a time prior to deserialization. Within each SERDES channel, a slip circuit slips the corresponding serial data stream by one bit (i.e., one unit interval (UI)) by extending the high portion of the duty cycle of a corresponding clock signal. The high portion of the clock signal is extended using a 3-to-1 mux that selects a fixed high signal, such as the high power supply rail, as an intermediate mux output signal whenever transitioning between two different applied clock signals that are offset from one another by one UI. In this way, the slip circuit avoids glitches that might otherwise result from switching directly between the two clock signals.

Abstract: A clock buffer circuit that generates a clock signal having a random cycle and duty from an input clock signal and a data output circuit including the same. The clock buffer circuit includes a buffer unit configured to receive an input clock signal and generate an internal clock signal and a first clock signal; a delay controller configured to receive the internal clock signal from the buffer unit and generate a delayed control signal according to a first control signal and a second control signal; and a delay unit configured to generate a second clock signal according to the first clock signal received from the buffer unit and the second clock signal received from the delay controller. The delay unit is configured to generate the second clock signal by randomly delaying transmission of the first clock signal.

Abstract: A skew adjustor that can reduce inter-pair skew between differential signals received via a cable is disclosed. In one embodiment, a skew adjustor includes: a skew detector that receives signals from a cable, and provides a detected skew amount when skew is detected between two of the signals; an offset controller for receiving the detected skew amount, and for providing a delay control signal in response thereto; and a skew delay circuit that receives the signals and the delay control signal, and enables one or more delay stages in a path of a first arriving of the two skewed signals based on the delay control signal, such that an adjusted skew between the two skewed signals at an output of the skew delay circuit is less than the detected skew amount by an amount corresponding to the enabled one or more delay stages.

Abstract: A delay circuit includes a pulse generation unit configured to generate a pulse signal, which is activated in response to an input signal and has a pulse width corresponding to delay information, and an output unit configured to activate a final output signal in response to a deactivation of the pulse signal.

Abstract: An A/D conversion circuit includes a pulse transit circuit, first and second pulse transit position detection circuits, and a digital signal generation circuit. The first pulse transit position detection circuit detects a transit position of the pulse signal output from the pulse transit circuit and generates a logical signal according to the transit position. The second pulse transit position detection circuit detects the circling number of the pulse signal output from the pulse transit circuit and generates a logical signal according to the circling number. The digital signal generation circuit synthesizes the logical signals output from the first and second pulse transit position detection circuits and generates a digital signal according to a size of an analog signal VA.

Abstract: A system and a method for determining a result of applying a function to signals is disclosed. The function is a polynomial function including monomials, in which the first signal in a first power forming a first part of the monomial and the second signal in a second power forming a second part of the monomial, wherein the first part of the monomial encrypted with a key is a first encrypted signal, and the second part of the monomial encrypted with the key is a second encrypted signal, comprising the steps of transmitting a first input signal encrypted with a second public key to the second processor, wherein the first input signal includes the first encrypted signal, transmitting a second input signal encrypted with a first public key to the first processor, wherein the second input signal includes a product of the first encrypted signal and the second encrypted signal.

Abstract: An embodiment of the invention comprises a digital phase detector with substantially zero phase offset. The digital phase detector receives a clock signal and a reference clock signal and provides a phase indicator signal to identify whether the clock signal leads or lags the reference clock signal. An embodiment of the invention comprises a method that adds substantially zero phase offset in processing an input clock signal and a delayed clock signal to generate a control signal. The control signal is processed in a variable delay line to generate the delayed clock signal. In an embodiment, a first processor comprises a delay locked loop having a digital phase detector, the digital phase detector comprising a first differential sense amplifier cross-coupled to a second differential sense amplifier, the digital phase detector receiving a clock signal and generating one or more delayed clock signals, a control signal, and a gated data signal.

Abstract: One embodiment of the present invention relates to a system for calibrating of timing between an amplifier input signal and a modulated supply power. The system includes a supply modulation component, an error metric component, and a delay determiner. The supply modulation component provides the modulated supply power and the amplifier input signal according to an input signal and a set delay signal. The error metric component provides information from a transmitted amplitude signal and a received amplitude signal. The delay determiner generates timing adjustments in the form of the set delay signal from the error metric information.

Abstract: A control device (1) and a triggering device (2) are coupled to one another for data processing. The control device and the triggering device (2) are electronic devices. The control device (1) determines a respective desired position value (p*) for at least one shaft with an interpolation cycle (T) and transmits a time delay (t) to the triggering device (2). The triggering device (2) monitors when the time delay (t) expires from transmission of the time delay (t) and then outputs a trigger pulse (I).

Abstract: A phase correction circuit includes a skew detection unit configured to generate first skew detection signals and second skew detection signals by comparing multi-phase signals with one another, a phase control signal generation unit configured to generate a plurality of phase control signals by combining the first skew detection signals with the second skew detection signals, and a phase adjustment unit configured to delay the multi-phase signals by delay time corresponding to the plurality of the phase control signals.

Abstract: A method for controlling a hold buffer delay is provided. A control voltage is generated in response to a measurement of at least one of process variation, temperature variation, and supply voltage variation to compensate for a hold violation, and the delay of a buffer is adjusted using the control voltage. A first data signal is provided in synchronization with a first clock signal. A logic operation is performed on the first signal so as to generate a second data signal. A third data signal is generated and outputted in synchronization with a second clock signal, and at least one of the first and second data signals is buffered with the buffer.

Abstract: A process, voltage, and temperature (PVT) compensation circuit and a method of continuously generating a delay measure are provided. The compensation circuit includes two delay lines, each delay line providing a delay output. The two delay lines may each include a number of delay elements, which in turn may include one or more current-starved inverters. The number of delay lines may differ between the two delay lines. The delay outputs are provided to a combining circuit that determines an offset pulse based on the two delay outputs and then averages the voltage of the offset pulse to determine a delay measure. The delay measure may be one or more currents or voltages indicating an amount of PVT compensation to apply to input or output signals of an application circuit, such as a memory-bus driver, dynamic random access memory (DRAM), a synchronous DRAM, a processor or other clocked circuit.

Abstract: Apparatuses and methods for compensating for differing power supply sensitivities of a circuit in a clock path. One such method includes altering signal timing of at least one of reference and feedback clock signals differently according to variations in power supply voltage to compensate for differences in delay power supply sensitivities of delays of a forward clock path and of a feedback clock path. Another example method includes providing an output clock signal in phase with an input clock signal and compensating for delay error between delays used in providing at least some of the delay of the output clock signal relative to the input clock signal by providing delays having power supply sensitivities resulting in a combined power supply sensitivity that is inverse to the delay error.

Abstract: A semiconductor apparatus is provided. The apparatus includes a transmission control unit configured to generate, in response to a received pulse signal having a first pulse width, transmission control signals with a second pulse width larger than the first pulse width and synchronization control signals with a third pulse width larger than the second pulse width. The apparatus also includes a reception control unit configured to generate reception control signals in response to the synchronization control signals.

Abstract: Embodiments provide systems and methods for dynamically regulating the clock frequency of an integrated circuit (IC) based on the IC supply voltage. By doing so, the clock frequency is no longer constrained by a worst-case voltage level, and a higher effective clock frequency can be supported, increasing the IC performance. Embodiments include a wave clocking system which uses a plurality of delay chains configured to match substantially the delays of respective logic paths of the IC. As the delays of the logic paths vary with supply voltage and temperature changes, the delay chains matched to the logic paths experience substantially similar changes and are used to regulate the clock frequency of the IC.

Abstract: Disclosed herein is a device that includes a plurality of one-shot pulse generation circuits connected in series between an input node and an output node. Each of the one-shot pulse generation circuits receives an input clock signal supplied from previously connected one-shot pulse generation circuit to output an output clock signal to subsequently connected one-shot pulse generation circuit. Both of a rising edge and a falling edge of the output clock signal are controlled based on one of a rising edge and a falling edge of the input clock signal. A time period from one of the rising edge and the falling edge of the output clock signal to the other of the rising edge and the falling edge of the output clock signal being variable.

Abstract: A source driver with an automatic de-skew capability is configured to receive a data signal and a clock signal from a timing controller, which are configured to drive a liquid crystal display panel. The source driver includes a signal delay unit, a setup time register, a hold time register, a first signal delay unit, a second delay unit and a logic circuit. In one embodiment of the present disclosure, the first data delay signal is configured to sample the second clock delay signal and the second data delay signal is configured to sample the first clock delay signal.

Abstract: The domain crossing circuit of a semiconductor memory apparatus for improving a timing margin includes a sampler that provides a sampling internal signal generated by delaying an internal input signal by a predetermined time in response to a clock and an edge information signal that defines an output timing of the sampling internal signal and an output stage that allows the sampling internal signal to be synchronized with the clock in response to the edge information signal to be output as a final output signal.

Abstract: A digital phase locked loop (300) configured to receive a reference clock signal (302) and a channel control word (308), and to generate an output clock signal (304). The digital phase locked loop comprising an adjustable delay component (306) configured to: receive the reference clock signal (302), apply a time delay to the reference clock signal (302) in accordance with a time delay control signal (316); and provide a delayed reference clock signal (318).

Abstract: A source synchronous signal synchronization system includes a differential signal receiver; a tunable input delay element coupled to the receiver; an input serializer/deserializer (ISerDes) coupled to the tunable input delay; an alignment unit coupled to the ISerDes; and a delay control unit coupled to the tunable input delay, the ISerDes, and the alignment unit.

Abstract: A memory controller receives data and phase-providing signals from a memory device. The phase-providing signal is not a clock signal, but is used by the memory controller to phase align a local data-sampling signal with the incoming data. The memory controller samples the data signal with the data-sampling signal. The memory controller can perform maintenance operations to update the phase relationship between the phase-providing and data-sampling signals.

Abstract: A data I/O interface for an integrated circuit device includes a noise detector receiving a power supply voltage, detecting a power supply voltage noise component, and providing a clock delay control signal in response to detected power supply voltage noise component. The data I/O interface also includes a clock delay circuit providing a delayed clock signal in response to the clock delay control signal, and a data transfer circuit powered by the power supply voltage and providing output data synchronously with the delayed clock signal.

Abstract: There is a need to ensure operation performance of a circuit region under DVFS control at low costs and highly precisely while a power-supply voltage change is made to the region. A first circuit (FVA) uses a first power-supply voltage (VDDA) for operation. A second circuit (NFVA) uses a second power-supply voltage (VDDB) for operation. A clock delay may be adjusted between paths for transmitting a clock to these circuits. When VDDA equals VDDB, a clock is distributed to FVA through a path that does not contain a delay device for phase adjustment. When the power-supply voltage for the FVA region is reduced, a clock is distributed to the FVA region based on a phase equivalent to one or two cycles of the clock displaced. Synchronization control is provided to synchronize clocks (CKAF and CKBF) and ensures operation so that a phase of two clocks to be compared fits in a range of design values while the power-supply voltage for the first circuit is changed.

Abstract: Provided is a PLL circuit including automatic frequency control circuit and an operating method thereof. The voltage controlled oscillator is primarily controlled by an automatic frequency control circuit, and is secondarily controlled by a loop filter. The voltage controlled oscillator outputs a coarsely-tuned oscillation signal when primarily controlled, and outputs a finely-tuned oscillation signal when secondarily controlled. The PLL circuit can have a quick frequency fixing time, and output the oscillation signal having a broad and stable frequency. Moreover, the noise characteristic of the PLL circuit is enhanced.

Abstract: A semiconductor device includes a delay circuit supplied with a first clock signal and a first phase determination signal and producing a second clock signal, the delay circuit controlling the second clock signal such that a delay in phase of the second clock signal to the first clock signal is increased when the first phase determination signal takes a first logic level and decreased when the first phase determination signal takes a second logic level, and a phase determining circuit supplied with the first clock signal and a third clock signal, which is produced in response to the second clock signal, and producing a second phase determination signal in response to a difference in phase between the first clock signal and the third clock signal.

Abstract: A semiconductor device includes an on-die termination circuit, a clock input unit, a clock phase mixing unit, and a data input/output unit. The on-die termination circuit is configured to calibrate a resistance of a termination pad and output an impedance matching code. The clock input unit is configured to receive a data clock. The clock phase mixing unit is configured to receive the data clock through the clock input unit and a delayed data clock, which is generated by delaying the data clock by a predetermined time, mix a phase of the data clock and a phase of the delayed data clock at a ratio corresponding to the impedance matching code, and output a phase-mixed data clock. The data input/output unit is configured to input/output a data signal in response to the phase-mixed data clock.

Abstract: Provided is a memory interface circuit connected to a memory device that outputs a first data signal, and including: a first delay unit delaying a first strobe signal outputted from the memory device by a first delay amount to generate a first delayed strobe signal; a first data latch unit latching the first data signal as a first latched data signal in synchronization with the first delayed strobe signal; a first range calculating unit calculating a first delay range width that is a width of a range of values of the first delay amount which allow the first data latch unit to correctly latch the first data signal as the first latched data signal; and a drive capability setting unit adjusting the drive capability of the memory device so as to widen the first delay range width.

Abstract: The frequency decision device determines frequency of the measured rectangular signal by simple and easy means. The frequency decision device inputs the measured rectangular signal that frequency (or period) changes dynamically. It generates a rectangular reference signal of predetermined on width ? synchronizing to the edge based on a positive going edge of this measured rectangle signal. And it watches the order of measured rectangle signal and falling edges of the rectangular reference signal. When this sequential order reversed, it detects that length of the ON time of ON time of the measured rectangle signal and the measured rectangular signal reversed.

Abstract: An integrated circuit device includes first circuitry including first logic devices and a clock tree for distributing a clock signal to the first logic devices and second circuitry including second logic devices and a clock gater operable to receive the clock signal and distribute the clock signal to the second logic devices. The clock gater comprises a programmable delay circuit.

Abstract: A method, new use for Look-Up Tables (LUTs), and a Field Programmable Gate Array (FPGA) chipset are provided for delaying data signals. The FPGA comprises an input and a set of LUTs operationally connected to and receiving from the interface a data signal and a clock signal. The set of LUTs delay the data signal by a delay so that a corresponding first delayed data signal output from the set of LUTs is so synchronized with the clock signal for appropriate sampling of the delayed data signal to be performed by the FPGA chipset. A process of manufacturing of the FPGA chipset comprises calculating a delay for delaying and synchronising the data signal with a clock signal to meet requirements of the chipset, calculating a number of LUTs for delaying the data signal, and implementing in a data path of the data signal the number of LUTs.

Abstract: An integrated circuit device includes a clock delay circuit configured to receive a clock signal and a pulse signal and to produce an output signal therefrom. The clock delay circuit is configured to transition the output signal to a first state responsive to a first state of the clock signal and to transition the output signal to a second state responsive to a first state transition of the pulse signal. The integrated circuit device further includes a pulse generator circuit configured to receive the clock signal and the output signal and to produce the pulse signal therefrom. The pulse generator circuit is configured to generate the first state transition in the pulse signal responsive to a transition of the clock signal to a second state and to generate a second state transition in the pulse signal responsive to the transition of the output signal to the second state.

Abstract: A voltage hold circuit includes four switches, an operational amplifier and a capacitor. By turning the switches on and off, the operational amplifier functions as a unity-gain buffer. In the normal operation mode, the positive input end of the operational amplifier is coupled to a node, and the output end of the operational amplifier is coupled to the capacitor. Thus the voltage of the capacitor is equal to the voltage of the node. In the power off mode, the positive input end of the operational amplifier is coupled d to the capacitor, and the output end of the operational amplifier is coupled to the node. Thus the voltage of the node is equal to the voltage of the capacitor. Therefore, the voltage hold circuit is able to hold the voltage of the node in the power down state.

Abstract: Embodiments of phase-generation circuitry and methods for generating a multiphase signal with duty-cycle correction are generally described herein. The phase-generation circuitry may include a plurality of controllable delay stages arranged in series and phase detector circuitry. Each delay stage may be configured to phase shift a differential signal based on a control signal. The phase detector circuitry may be configured to generate the control signal based on a first time difference and a second time difference. The first time difference may be a time difference between rising edges of a first component of the differential signal and a second component of a phase-shifted signal. The second time difference may be a time difference between falling edges of the first component of the differential signal and the second component of the phase-shifted signal. Other circuits, systems, and methods are described.

Abstract: A frequency detector includes an error measurement unit measuring a time interval between zero-crossing points of an input signal that is modulated. An error conversion unit quantizes the measured time interval using one of modulation time intervals. An error calculation unit calculates a frequency error based upon a difference between the measured time interval and the quantized time interval. An error generation control unit controls whether to output the frequency error based upon the quantized time interval, the calculated frequency error, and a predetermined critical value.

Abstract: A repeater circuit is disclosed. The repeater circuit includes an input circuit coupled to receive a data input signal and a clock signal, and an output circuit configured to, when activated, drive an output signal on an output node. The input circuit is further configured to activate the output circuit in order to initiate a logical transition of the data output signal. A deactivation circuit is configured to deactivate the output circuit at a delay subsequent to activation. A latch is coupled to the output circuit and it is configured to change a latch output state responsive to activation of the output circuit. The latch is configured to hold a state of the output node subsequent to deactivation of the output circuit. The input circuit is configured to activate the output circuit dependent on the clock signal. The deactivation circuit is configured to deactivate the output circuit independent of the clock signal.

Abstract: Disclosed herein is a device that includes a clock generation circuit that generates an internal clock signal during a normal operation and stops generation of the internal clock signal during a wafer-level burn-in test, a clock tree line that transmits the internal clock signal, and a selector that supplies a dummy clock signal, which is different from the internal clock signal, to the clock tree line during the wafer-level burn-in test.

Abstract: A delay locked loop includes initialization circuitry that ensures that a DLL is initialized to an operating point that is not to close to either end of a delay vs. control voltage characteristic. The initialization circuitry forces the DLL to initially search for a lock point starting from an initial delay, the delay is varied in one direction, forcing the DLL to skip the first lock point. The initialization circuitry only allows the DLL to vary the delay of the voltage controlled delay loop in the one direction from the initial delay until the operating point is reached.

Abstract: A DLL circuit which can prevent transition to a pseudo lock state is provided. The DLL circuit includes a delay stage to which a reference clock is input and in which variable delay elements D able to change an amount of delay are connected in a plurality of stages, a phase comparator (PH Comp) which compares the phase of the reference clock to the phase of one delay signal extracted from the delay stage, a delay control circuit which performs delay control of the delay element in the delay stage on the basis of the comparison result by the phase-comparison means, and a DFF which detects a phase relationship of at least two delay signals extracted from the delay stage to discriminate a state which is not a normal lock state and controls the delay control circuit to perform state transition to the normal lock state.