Abstract: A semiconductor device, a semiconductor system, and a control method of a semiconductor device are capable of accurately monitoring the lowest operating voltage of a circuit to be monitored. According to one embodiment, a monitor unit of a semiconductor system includes a voltage monitor that is driven by a second power supply voltage different from a first power supply voltage supplied to an internal circuit that is a circuit to be monitored and monitors the first power supply voltage, and a delay monitor that is driven by the first power supply voltage and monitors the signal propagation period of time of a critical path in the internal circuit.

Abstract: A digital measurement circuit includes a first input flip-flop which receives a first signal through a data input terminal, receives a first clock signal through a clock input terminal, and outputs a second signal; a second input flip-flop which receives the second signal through a data input terminal, receives a second clock signal, which is an inverted signal of the first clock signal, through a clock input terminal, and outputs a third signal; and a delay line which receives the second signal and outputs first through n-th output signals, wherein n is an integer greater than one, and the first through n-th output signals are sampled based on the third signal to output first through n-th sampling signals is provided.

Abstract: The present disclosure provides a display panel, a driving method and a display device. The display panel includes first data lines and first gate lines in an auxiliary display area, a first scanning unit, M second scanning units, M switch unit groups corresponding to the M second scanning units, M second data lines corresponding to the M switch unit groups, where M is an integer greater than 1. Each second scanning unit has output terminals and a control terminal connected to a main driving chip. Each switch unit group includes a plurality of switch units having a plurality of control terminals connected to the output terminals of the second scanning unit, a plurality of first terminals respectively connected to the first data lines, and second terminals. Each second data lines is connected to the main driving chip and the second terminals of the switch units.

Abstract: A test apparatus may include transceivers and a global de-skew circuit. In a training mode, the transceivers provide first timing information obtained by delaying a first data signal in the range of up to a preset unit interval based on a clock signal and receive second timing information corresponding to timing differences between a slowest transceiver and the remaining transceivers. In an operation mode, the transceivers provide compensation data to a plurality of DUTs (Devices Under Test) substantially simultaneously. The compensation data may be obtained by delaying a second data signal by multiples of the preset unit interval in response to the second timing information. In the training mode, the global de-skew circuit receives the first timing information, calculates, using the first timing information, the timing differences between the slowest transceiver and the remaining transceivers, and provides the second timing information corresponding to the timing differences to the transceivers.

Abstract: According to one embodiment, the touch drive device includes a plurality of drive electrodes arranged side by side to extend in a single direction, a detection electrode which extends in a direction crossing the direction in which the drive electrodes extend, and generates capacitances at intersections of the detection electrode and the drive electrodes, and a driver (DDI) which groups the drive electrodes into a plurality of drive electrode portions each including at least one drive electrode, and performs a touch scanning drive by supplying a touch drive signal (TSVCOM) having a pulse waveform for detection of a closely situated external object to a target drive electrode portion which is a selected one of the drive electrode portions. The number of the drive electrodes included in each of the drive electrode portions and the target drive electrode portion to which the touch drive signal (TSVCOM) is supplied can be designated.

Abstract: A virtualization platform that provides a systematic, transparent and local testing of components hosted by the virtualization platform in their integrated context. The virtualization platform comprises integrated interceptor modules connected to the components via communication channels, each interceptor module being interposed in the communication channel connecting two components, and an integrated analyzing device connected to the interceptor modules and comprising a control device and a testing device. The control device is configured to put each interceptor module in an operational mode selected out of a set of predetermined operational modes including a testing mode. The testing device is configured to locally test the components connected to the interceptor modules being put in the testing mode.

Abstract: Techniques are disclosed relating to feedback-controlled oscillators (e.g., phase-locked loops) arranged in two or more levels. In some embodiments, in a relatively higher-frequency mode, a first level feedback-controlled oscillator provides reference signals to one or more second level feedback-controlled oscillators that in turn generate output clock signals to clock sequential circuitry. In some embodiments, in a relatively lower-frequency mode, the first level feedback-controlled oscillator bypasses the second level feedback-controlled oscillators and provides output clock signals directly to sequential circuitry (without using any intervening feedback-controlled oscillators).

Abstract: A clock generating device includes a first timing delay module, a multiplexer, and a second timing delay module. The multiplexer is electrically connected to the first timing delay module. The second timing delay module is electrically connected to the multiplexer. The first timing delay module generates a plurality of delayed clock signals based on a reference clock signal. The multiplexer outputs a first delayed clock signal and a second delayed clock signal, among the plurality of delayed clock signals, based on a clock generating signal. The second timing delay module generates an output clock signal based on the clock generating signal, the first delayed clock signal and the second delayed clock signal.

Abstract: Device and method for determining timing of a measured signal, the device has a plurality of flip-flop units (10), an evaluation module, an allocating module for allocating at least one path consisting of flip-flop units (10), and a calibration module being adapted for determining a time difference parameter of each flip-flop unit (10), the time difference parameter specifying for each flip-flop unit (10) a time difference between a period of time in which the measured signal (20) reaches the given flip-flop unit (10) and a period time in which the secondary signal reaches the given flip-flop unit (10), wherein the evaluation module is adapted for determining the timing of the measured signal from the output of the flip-flop units (10) located along the at least one path, on the basis of the time difference parameters.

Abstract: A system to generate an oscillator signal. The system includes a multi-stage oscillator, where each stage generates an output. The system also includes a first weighting circuit coupled to the multi-stage oscillator. The first weighting circuit taps the outputs of at least some of the stages and applies a first variable weighting factor to each output of the tapped stages to generate a first weighted output for each of the tapped stages. The system also includes a first summing circuit coupled to the first weighting circuit. The first summing circuit sums the first weighted outputs of the tapped stages to produce the oscillator signal.

Abstract: To accurately measure a frequency characteristic of a waveform generating apparatus, provided is a measurement apparatus that measures a frequency characteristic of a waveform generating apparatus generating a signal having a waveform corresponding to waveform data, comprising a control section that causes a plurality of sine wave signals having different frequencies to be sequentially output from the waveform generating apparatus; a measuring section that measures each of the sine wave signals output from the waveform generating apparatus; and a calculating section that calculates a frequency characteristic of the waveform generating apparatus based on the measurement results of the measuring section. The control section causes trigger signals to be output from the waveform generating apparatus and causes the sine wave signals to be output in synchronization with the trigger signals, and the measuring section measures a phase of each sine wave signal with the corresponding trigger signal as a reference.

Abstract: A critical path monitor (CPM) is configured in an integrated circuit (IC). The IC includes a set of critical paths. The CPM includes a set of split paths, a split path in the set of split paths corresponding to a critical path in the set of critical paths, and a split path in the set of split paths including an edge detector. The edge detector is configured with a set of edge detector latches. A set of set-reset (SR) latches is configured such that an edge detector latch is associated with a corresponding SR latch. A reset signal is configured to reach the set of edge detector latches in an offset synchronization with a latch clock signal used in the set of edge detector latches. The CPM is configured to operate using a frequency of the latch clock signal such that the frequency is higher than a threshold frequency.

Abstract: A timing skew characterization apparatus comprises a coarse timing skew characterization circuit, a fine timing skew characterization circuit and a coarse delay cell calibration circuit. The coarse timing skew characterization circuit comprises a plurality of coarse delay cells whose delays can be calibrated through the coarse delay cell calibration circuit. The calibration of fine delay cells can be implemented through a trail and error process. Both coarse delay step and fine delay step can be characterized through a single measurement setup. As a result, the timing skew characterization apparatus provides a high resolution setup and hold time measurement.

Abstract: A calibration circuit and a calibration method are provided. The calibration circuit has a delay circuit, a phase detector, and a controller. The delay circuit delays an input signal to output an output signal, wherein a delay time between the input signal and the output signal is related to an equivalent capacitance and an equivalent resistance of the delay circuit. The phase detector coupled to the delay circuit compares the phases of the input signal and the output signal. The controller coupled to the delay circuit and the phase detector generates a control signal according to the comparison result of the phase detector to adjust the equivalent resistance of the delay circuit.

Abstract: Delay associated with each of two signals along respective transmission paths is accurately measured using a delay measurement circuit that is fabricated in situ on the actual device where the circuitry for propagating the two signals is fabricated. Thus, the measured delay associated with each of the two signals is subject to the same fabrication-dependent attributes that affect the actual circuitry through which the two signals will be propagated during operation of the device. The skew between the two signals is quantified as the difference in the measured delays. Coarse and fine delay modules are defined within the transmission path of each of the two signals. Based on the measured skew between the two signals, the coarse and fine delay modules are appropriately set to compensate for the skew. The appropriately settings for the coarse and fine delay modules can be stored in non-volatile memory elements.

Abstract: A circuit and method provide built-in measurement of delay changes in integrated circuit paths. The circuit includes a digital shift register to access multiple paths, and may be implemented in digital boundary scan to test I/O pin delays. Synchronous to a first frequency, the circuit applies an alternating signal to the paths and samples the paths' output logic values synchronous with a second frequency that is asynchronous and coherent to the first clock frequency. The shift register conveys the samples to a modulo counter that counts the number of samples between consecutive rising or consecutive falling edges in the signal samples from a selected path. Between the two edges, the path or a path characteristic is changed, and the resulting modulo count after the second edge is proportional to the change in delay. The circuit can compare the count, or the difference between counts, to test limits.

Abstract: Provided is a measurement apparatus that measures a signal under measurement, comprising a first oscillation circuit that receives one pulse of the signal under measurement and begins oscillating according to the pulse of the signal under measurement to output a first oscillated signal; a second oscillation circuit that receives one pulse of a reference signal and begins oscillating according to the pulse of the reference signal to output a second oscillated signal having a period that is different from a period of the first oscillated signal; and a first sampling section that samples the first oscillated signal according to a pulse of the second oscillated signal. The first oscillation circuit and the second oscillation circuit each include a control section that selects one pulse; a delay section that delays the pulse; and a loop line that feeds the pulse back to an input terminal of the delay section.

Abstract: A path of a signal extends from an initial point through first and second cells to an end point. The signal is supplied as a first signal to the first cell and outputted therefrom as a second signal. The signal is supplied as a third signal to the second cell and outputted therefrom as a fourth signal. First delay amounts of the signal in the first cell and a transition time of the second signal are calculated based on a transition time of the first signal and a voltage supplied to the first cell. Second delay amounts of the signal in the second cell and a transition time of the fourth signal are calculated similarly. Here, the transition time of the second signal is set to be a transition time of the third signal. Jitter values in the end point are calculated based on the first and second amounts.

Abstract: A critical path monitor having selectable data output modes provides additional information about critical path delay variation. A pulse is propagated through a synthesized path representing a critical path in a functional logic circuit and a synthesized path delay is measured by a monitoring circuit that detects the arrival of an edge of the pulse at the output of the synthesized delay. The measured delay is provided as a real-time output and a processed result of the measured delay is processed according to a data output mode selected from multiple selectable output modes, thereby providing different information describing the real-time data about critical path delay, such as a range of edge positions corresponding to a variation of the critical path delay.

Abstract: Provided is a noise measurement apparatus that measures noise at a location under measurement, comprising a self-excited oscillator that is provided at the location under measurement and that outputs an oscillation signal in which is sequentially accumulated, in each cycle, the noise at the location under measurement; a transmission path that transmits the oscillation signal output by the self-excited oscillator; and a measuring unit that measures noise added to the oscillation signal transmitted through the transmission path. The measuring unit may measure the noise at the location under measurement by differentiating noise added to the oscillation signal transmitted through the transmission path.

Abstract: A phase locked loop device includes a phase detector that measures a difference in phase between a reference clock signal and an output clock signal of the phase locked loop. The phase detector provides a pulse having a width indicative of the phase difference. A phase measurement module determines a digital value based on the pulse width. Accordingly, the digital value provides an indication of the phase difference between the reference clock signal and the output clock signal. A series of the digital values can be recorded to indicate how the phase difference varies over time, thereby providing a useful characterization of device behavior.

Abstract: A system and method for characterizing process variations are provided. A circuit comprises a plurality of inverters arranged in a sequential loop, and a plurality of transmission gates, with each transmission gate coupled between a pair of serially arranged inverters. Each transmission gate comprises a first field effect transistor (FET) having a first channel, and a second FET having a second channel. The first channel and the second channel are coupled in parallel and a gate terminal of the first FET and a gate terminal of the second FET are coupled to a first control signal and a second control signal, respectively.

Abstract: A test structure for gathering switching history effect statistics includes a waveform generator circuit that selectively generates a first test waveform representative of a 1SW transistor switching event, and a second test waveform representative of a 2SW transistor switching event; and a history element circuit coupled to the waveform generator circuit, the history element circuit including a device under test (DUT) therein, and a variable delay chain therein, wherein a selected one of the first and second test waveforms are input to the DUT and the variable delay chain; wherein the history element circuit determines fractional a change in signal propagation delay through the DUT between the 1SW and 2SW transistor switching events, with the fractional change in signal propagation delay calibrated with timing measurements of a variable frequency ring oscillator; and wherein the test structure utilizes only external low-speed input and output signals with respect to a chip.

Abstract: An apparatus and method for measuring the duty cycle of a clock signal, the apparatus having a first multi-tap delay module, a second multi-tap delay module, and a multi-element detecting module, the input terminal of the first multi-tap delay module and the input terminal of the second multi-tap delay module coupled to an input node IN, the first multi-tap delay module receiving the clock signal and then providing it a first constant incremental delay at each tap, the second multi-tap delay module receiving the same clock signal CLK and then providing it a second constant incremental delay at each tap, and the multi-element detecting module determining the ratio of the number of outputs of the multi-element detecting module in which the sampled clock level is high with respect to the total number of steps covering one complete clock cycle.

Abstract: A test structure for an integrated circuit device includes one or more experiments selectively configured to receive one or more high-speed input signals as inputs thereto and to output at least one high-speed output signal therefrom, the one or more experiments each including two or more logic gates configured to determine differential delay characteristics of individual circuit devices, at a precision level on the order of picoseconds to less than 1 picosecond; and wherein the one or more sets of experiments are disposed, and are fully testable, at a first level of metal wiring (M1) in the integrated circuit device.

Abstract: A digital signal delay measuring circuit for measuring a delay time of a digital signal of a scan-testable digital circuit inside a device to be tested is provided. The circuit includes: outputting means for outputting a delay time measuring signal as a digital signal; delay means for delaying a timing when a state of the delay time measuring signal is changed; and at least two signal holding means, each receiving the delay time measuring signal and holding the state of the delay time measuring signal at a holding-command input timing.

Abstract: Provided is a semiconductor integrated circuit including: a first path that includes a first logic circuit; a second path that includes a second logic circuit; and a subsequent-stage circuit that is connected to an output of the first path and is connected to an output of the second path, in which the second path further includes a first internal path that is selected as a propagation path during a normal operation period; and a second internal path that is selected as a propagation path during a test operation period and includes a delay circuit having a delay amount larger than a delay amount of the first internal path.

Abstract: Described is a compact, lower power gated ring oscillator time-to-digital converter that achieves first order noise shaping of quantization noise using a digital implementation. The gated ring oscillator time-to-digital converter includes a plurality of delay stages configured to enable propagation of a transitioning signal through the delay stages during an enabled state and configured to inhibit propagation of the transitioning signal through the delay stages during a disabled state. Delay stages are interconnected to allow sustained transitions to propagate through the delay stages during the enabled state and to preserve a state of the gated ring oscillator time-to-digital converter during the disabled state. The state represents a time resolution that is finer than the delay of at least one of the delay stages. A measurement module determines the number of transitions of the delay stages.

Abstract: A frequency measuring circuit and a semiconductor device having the frequency measuring circuit include a divided and shifted clock signal generator, a delayed clock signal generator and a phase detecting unit. The divided and shifted clock signal generator divides a frequency of a clock signal input from an exterior to output a frequency-divided clock signal, and delays the frequency-divided clock signal by a time proportional to a period of the clock signal to output a shifted clock signal. The delayed clock signal generator delays the frequency-divided clock signal by a fixed time to generate a plurality of delayed clock signals. The phase detecting unit receives the plurality of delayed clock signals and the shifted clock signal and detects a phase difference between each of the plurality of delayed clock signals and the shifted clock signal to output a plurality of phase detecting signals that represent information related to a frequency of the clock signal.

Abstract: A delay line calibration circuit is disclosed herein. The calibration circuit has an arbiter circuit having a unit for determining which of two signals that arrive first; a first and a second synchronous element each having an input for receiving a clock signal, and one of them having a unit for outputting the clock signal a clock period later; and a calibration circuit having inputs connected to the outputs of the arbiter circuit for receiving a signal from it indicative of whether the signal input to the arbiter circuit from the delay line is ahead or after the signal input to the arbiter circuit from the second element, the calibration circuit further being connected to the delay line for calibrating the delay line in accordance with the signal received from the arbiter circuit. The invention in at least one embodiment provides improved calibration of delay lines.

Abstract: A circuit for testing phase detectors in a delay locked loop is provided. The circuit uses a second phase detector arranged to receive the signals entering a first phase detector. Particularly, the circuit is routed such that a signal entering the D input of the first phase detector is inputted into the clock input of the second phase detector, and a signal entering the clock input of the first phase detector is inputted into the D input of the second phase detector. The circuit is also coupled to a test controller located on-die or at a high volume manufacturing (HVM) tester.

Abstract: Delay associated with each of two signals along respective transmission paths is accurately measured using a delay measurement circuit that is fabricated in situ on the actual device where the circuitry for propagating the two signals is fabricated. Thus, the measured delay associated with each of the two signals is subject to the same fabrication-dependent attributes that affect the actual circuitry through which the two signals will be propagated during operation of the device. The skew between the two signals is quantified as the difference in the measured delays. Coarse and fine delay modules are defined within the transmission path of each of the two signals. Based on the measured skew between the two signals, the coarse and fine delay modules are appropriately set to compensate for the skew. The appropriately settings for the coarse and fine delay modules can be stored in non-volatile memory elements.

Abstract: A ring oscillation circuit, which can operate the ring oscillation due to a positive feedback stably and continuously, is provided and it is applied to an accurate measurement of delay time and a measurement of timing accuracy in a jitter of a clock signal or the like with a high accuracy. A ring oscillation circuit comprises a delay circuit and a monostable multivibrator. An output of the delay circuit is connected to an input of the monostable multivibrator, an output of the monostable multivibrator is connected to an input of the delay circuit, and the delay circuit and the monostable multivibrator configure a positive feedback loop. An oscillation starting circuit for starting oscillation upon receipt of an input of a trigger pulse for triggering oscillation is provided on the positive feedback loop, or in the inside of the delay circuit or the monostable multivibrator.

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: According to the methods of the invention, a further delayed DLL signal is compared to the reference clock and a delayed reference clock signal is compared to a DLL signal. These two comparisons are performed on the 360° signal and on the 180° signal. The delay introduced by the methods of the invention is preferably adjustable based on the results of a process monitor test. The process monitor test can be run continuously and accounts for process, voltage and temperature. The methods of the invention can also be used to test for clock skew in a clock tree on a chip.

Abstract: A clock test apparatus for a semiconductor integrated circuit includes a delay unit configured to delay an internal clock signal. A comparison unit compares the phase of an output signal of the delay unit with the phase of a reference clock signal. A phase discrimination unit receives a test mode signal, the reference clock signal, and an output signal of the comparison unit, thereby outputting a discrimination signal.

Abstract: Delay associated with each of two signals along respective transmission paths is accurately measured using a delay measurement circuit that is fabricated in situ on the actual device where the circuitry for propagating the two signals is fabricated. Thus, the measured delay associated with each of the two signals is subject to the same fabrication-dependent attributes that affect the actual circuitry through which the two signals will be propagated during operation of the device. The skew between the two signals is quantified as the difference in the measured delays. Coarse and fine delay modules are defined within the transmission path of each of the two signals. Based on the measured skew between the two signals, the coarse and fine delay modules are appropriately set to compensate for the skew. The appropriately settings for the coarse and fine delay modules can be stored in non-volatile memory elements.

Abstract: A built-in self-test system for a dynamic random access memory device using a data output register of the memory device to apply test signals to data bus terminals and a data strobe terminal of the memory device responsive to respective clock signals. The clock signal are generated by a test system oscillator and coupled through a clock tree of the memory device. The test system further includes a selector that sequentially selects each of the test signals applied to the data bus terminals and applies the selected test signal to a multi-phase generator. The multi-phase generator delays the selected signal by different time to generate a set of delayed signals. The phases of the delayed signals are compared to the test signal applied to the data strobe terminal to determine the delay of the compared signals relative to each other, thereby determining the timing parameter.

Abstract: A memory controller includes a variable delay circuit for phase-shifting a signal and an interface circuit suited for performing a test of a controller so that the memory controller realizes a test of a delay failure detection in a real-time speed operation at the time of the test.

Abstract: There is provided an electronic device for receiving an input data signal and an input clock signal that indicates a timing to obtain the input data signal. The electronic device includes a first adjusting section that adjusts a phase difference between the input data signal and the input clock signal so as to be equal to a first phase difference, and outputs the resulting signals as a first data signal and a first clock signal, a phase varying section that outputs a second clock signal having a designated phase difference with respect to the first clock signal, and a second adjusting section that adjusts the phase difference of the second clock signal with respect to the first clock signal so as to be equal to a second phase difference, based on a result of obtaining the first clock signal at a varying timing of the second clock signal.

Abstract: There is provided a timing generator for generating a timing signal based on a given reference clock, having a delaying circuit section for outputting each pulse of the reference clock by delaying by a value of delay given per each of the pulse and a pulse selecting and outputting section for passing and outputting only pulses to be outputted as the timing signal among the pulses outputted out of the delaying circuit section.

Abstract: A calibration apparatus includes an RC integrator circuit. The calibration apparatus further includes a bandwidth setting controller to provide a bandwidth setting code indicating a reference bandwidth value for calibration of the RC integrator circuit and a capacitance code generator, coupled to the RC integrator circuit, to generate a capacitance code to adjust a capacitance of the RC integrator circuit using the bandwidth setting code and a current capacitance value of the RC integrator circuit.

Abstract: A circuit and method for determining operating speed of a clock associated with an integrated circuit (IC), includes an IC logic element, a scan chain, and a calibration circuit including a first plurality of flip-flops and a combinational delay line. The calibration circuit operates in a functional test mode and in a scan test mode to determine a clock signal delay between the functional test mode and the scan test mode.

Abstract: Techniques for inline measurement of switching delay history effects in an integrated circuit device are provided. A pulse is launched down a delay chain. The pulse is substantially synchronized with a signal of a ring oscillator. The delay chain and the ring oscillator comprise substantially identical gates to a defined point on the ring oscillator corresponding to a far end of the delay chain. At least one difference in a number of gates traversed by an edge of the signal in the ring oscillator and a number of gates traversed by a corresponding edge of the pulse in the delay chain is measured when the pulse reaches the far end of the delay chain. One or more switching histories in the integrated circuit device are determined in accordance with the at least one measured difference in the number of gates traversed by an edge of the signal and a corresponding edge of the pulse.

Abstract: A high frequency delay circuit operable to output a high frequency signal delayed for a desired delay time. The high frequency delay circuit includes: a variable delay circuit operable to receive a reference signal of which a frequency is lower than the high frequency signal, and to output a delay reference signal delayed from the reference signal for the desired delay time in advance; and a multiplier operable to generate the high frequency signal, of which a frequency is a frequency of the delay reference signal multiplied by a predetermined value, and to output the generated high frequency signal at timing according to a phase of the delay reference signal.

Abstract: A circuit board with a processing unit and a delay line with a controllable number of delay elements fabricated thereon includes apparatus for testing and calibrating the delay line elements. In the test mode, a calibrated pulse is delayed by the delay line while determining the logic state of pulse at two times, the interval between the two times being the same as the pulse width. By adding delay elements, the period of the calibrated pulse as a function of number of delay elements can determine the delay of each delay element. In the calibration mode, the delay line is configured as a ring oscillator and the frequency of the ring oscillator as a function of number of delay elements provides the time delay for the individual elements.

Abstract: According to the methods of the invention, a further delayed DLL signal is compared to the reference clock and a delayed reference clock signal is compared to a DLL signal. These two comparisons are performed on the 360° signal and on the 180° signal. The delay introduced by the methods of the invention is preferably adjustable based on the results of a process monitor test. The process monitor test can be run continuously and accounts for process, voltage and temperature. The methods of the invention can also be used to test for clock skew in a clock tree on a chip.

Abstract: Delay-locked loops, signal locking methods and devices and systems incorporating delay-locked loops are described. A delay-locked loop includes a forward delay path, a feedback delay path, a phase detector and a timer circuit. The forward delay path alternatively couples to an external clock signal and to an internal test signal. The phase detector adjusts a delay line based upon the phase differences of a feedback signal and the external clock signal. The timer circuit switches the internal test signal into the forward delay path and measures the time of traversal of the internal test signal around the forward delay path and the feedback delay path and generates a time constant for configuring the phase detector's update period. The phase detector is thereafter able to stabilize at an improved rate.

Abstract: A built-in self-test system for a dynamic random access memory device using a data output register of the memory device to apply test signals to data bus terminals and a data strobe terminal of the memory device responsive to respective clock signals. The clock signal are generated by a test system oscillator and coupled through a clock tree of the memory device. The test system further includes a selector that sequentially selects each of the test signals applied to the data bus terminals and applies the selected test signal to a multi-phase generator. The multi-phase generator delays the selected signal by different time to generate a set of delayed signals. The phases of the delayed signals are compared to the test signal applied to the data strobe terminal to determine the delay of the compared signals relative to each other, thereby determining the timing parameter.

Abstract: For one disclosed embodiment, a delay is to receive signals and to delay received signals for an amount of time at least partially dependent on a supply voltage to generate delayed signals. Logic is to help measure a characteristic relating to the supply voltage based at least in part on the delayed signals. Other embodiments are also disclosed.