Abstract: A multi-phase clock generator including a first delay locked loop, a reference signal generator and a second delay locked loop is provided. The first delay locked loop generates 2N phase clock signals according to an input clock signal, so as to equally divide a clock period of the input clock signal into 2N predetermined phases, where N is a positive integer. The reference signal generator selects two phase clock signals according to a digital signal, and adjusts an output ratio of the two phase clock signals in 2M clock periods to serve as a reference clock signal. The second delay locked loop delays a first phase clock signal according to a phase difference between the reference clock signal and an output clock signal. In this way, each predetermined phase is further equally divided into 2M sub-phases, so that the multi-phase clock generator has 2(N+M) phase selections.

Abstract: A clock-switching circuit having at least two inputs for receiving at least two different clock sources, an output for providing a selected one of the clock sources, and a switch for selecting the one of the inputs to provide on the output, the switch including elements that, prevent the providing of a truncated version of any of the clock sources on the output, always provide a clock signal on the output, and always maintain phase alignment and pulse ratio of the clock sources on the output.

Abstract: A glitch free clock switching circuit includes a first enable synchronization logic that generates a first clock enable in response to a first enable from a first enable generation logic. The clock switching circuit includes a second enable synchronization logic that generates a second clock enable in response to a second enable from a second enable generation logic. A logic gate is coupled to an output of the second enable synchronization logic that selects the second clock signal as a logic gate output if the second enable is logic high. A priority multiplexer receives a first clock signal, the first enable and the logic gate output. The multiplexer configured to select the first clock signal as the clock output if the first enable is logic high, irrespective of the logic gate output.

Abstract: Low jitter clock interpolator circuits in accordance with embodiments of the invention are illustrated. In many embodiments, the low jitter clock interpolator incorporates a time based numerically controlled oscillator (NCO) to generate a clock signal, and different phases of the resulting clock are created using a clock interpolator. Information from the time based NCO and the interpolator is then used to select phases and create an output clock that is jitter free within the precision of the interpolator.

Abstract: A clock generation circuit is provided, having a bandgap reference circuit, a frequency controlled resistor, a comparison circuit and a voltage controlled oscillator. The bandgap reference circuit generates a first voltage. The frequency controlled resistor is coupled to a first node to provide a second voltage. The comparison circuit generates a first current according to a difference between the first voltage and the second voltage. The voltage controlled oscillator outputs first, second and third output clocks according to a third voltage on a second node, wherein the third voltage is generated according to the first current, and the second and third output clocks are fed back to the frequency controlled resistor such that the frequency controlled resistor converts the first current into the second voltage according to the second and third output clocks.

Abstract: A clock phase recovery apparatus includes a clock estimator for estimating a first clock signal and a second clock signal upon the basis of an input signal, the input signal comprising a first sub-signal according to a first optical polarization and a second sub-signal according to a second optical polarization, the first clock signal comprising a first clock magnitude and a first clock phase, the second clock signal comprising a second clock magnitude and a second clock phase, and a selector for selecting the first clock phase to form the estimated clock phase if the first clock magnitude is greater than the second clock magnitude, or for selecting the second clock phase to form the estimated clock phase if the second clock magnitude is greater than the first clock magnitude.

Abstract: A clock generator includes a first latch configured to output a first intermediate clock phase signal based on a first clock signal and a second intermediate clock phase signal. A first phase interpolation circuit has a first input coupled to a first input of the first latch and a second input coupled to a first output of the first latch. The first phase interpolation circuit is configured to output a first clock phase signal based on the first and second intermediate clock phase signals.

Abstract: A resonant clock distribution network architecture is proposed that enables a resonant clock network to track the impact of parameter variations on the insertion delay of a conventional clock distribution network, thus limiting clock skew between the two networks and yielding increased performance. Such a network is generally applicable to semiconductor devices with various clock frequencies, and high-performance and low-power clocking requirements such as microprocessors, ASICs, and SOCs.

Abstract: A mobile communication device includes an analog clock and a digital clock circuit. The analog clock circuit is configured to generate an oscillating output. The digital clock circuit is configured to generate a digital clock output having a frequency that is substantially equal to the frequency of the oscillating output.

Abstract: A control system includes a clock gating module and a clock comparison module. The clock gating module is configured to generate a gating signal based on an enable signal, a given period, and a base clock signal having a given frequency. The clock comparison module is configured to generate a gated clock signal based on the base clock signal and the gating signal.

Abstract: A clock-switching circuit having at least two inputs for receiving at least two different clock sources, an output for providing a selected one of the clock sources, and a switch for selecting the one of the inputs to provide on the output, the switch including elements that, prevent the providing of a truncated version of any of the clock sources on the output, always provide a clock signal on the output, and always maintain phase alignment and pulse ratio of the clock sources on the output.

Abstract: A signal delay circuit including a clock transfer control circuit configured to transmit or block a clock signal, and a pulse signal generation circuit configured to delay a first pulse signal in response to the transmitted clock signal to generate a second pulse signal which has a longer active period than the first pulse signal.

Abstract: A glitchless clock multiplexer controlled by an asynchronous select signal for use in GPS receivers is disclosed. A device in accordance with the present invention comprises a device for producing a clock signal, the clock signal being selected from a plurality of asynchronous frequency sources.

Abstract: A phase generating apparatus generates an output clock having a desired phase according to a digital signal. The apparatus includes a phase selecting unit and a phase generating unit. The phase selecting unit selects one of a plurality of input clocks according to a portion of bits of the digital signal to generate a reference clock. Each of the input clocks respectively has a difference phase. The phase selecting unit divides the frequency of the reference clock, and selectively delays the frequency-divided reference clock according to another portion of bits of the digital signal to generate the output clock.

Abstract: A device includes a logic circuit having first, second, and third input ports, a first output port, and a feedback path between the first output port and the third input port. In a first operating state, a logic state change at the first input port triggers a logic state change at the first output port, but a logic state change at the third input port does not trigger a logic state change at the first output port. This allows signals to be routed through the device. In a second operating state, a logic state change of the third input port triggers a logic state change of the first output port. This change is fed back, delayed by a time value, to the third input to maintain an oscillation with at least two edges. The frequency of this oscillation is used to determine a value of a measurement variable.

Abstract: A clock signal for electronic circuitry is generated by generating, based on which one of a plurality of application use cases is presently active, a first signal that indicates a first selected one of a plurality of clock signal operating points. Based on the electronic circuitry's present speed requirement, a second signal is generated that indicates a second selected one of the clock signal operating points. For any given one of the application use cases, the speed requirement need not remain constant for the duration of the application use case. Based on whichever one of the first and second signals is associated with a higher clock frequency operating point, a third signal is generated that indicates which clock signal operating point (and possibly what voltage level) should be active. The third signal controls generation of a clock (and possibly also voltage level).

Abstract: Example embodiments are directed to a delay locked loop (DLL) circuit based on a hybrid finite impulse response (FIR) filtering technique, and a semiconductor memory device including the DLL circuit. The DLL circuit includes a frequency divider and a self-referenced multiphase generator (SRMG) and allows a Sigma-Delta (??) modulator to operate at a low frequency without generating false lock and glitch noise.

Abstract: Various embodiments of this disclosure may describe a circuit for transmitting data from a transmitting region of an integrated circuit to a receiving region of the integrated circuit. The circuit may level-shift the data to the appropriate voltage level and may have good tolerance to clock skews. Other embodiments, including an integrated circuit having the circuit or a system with the integrated circuit, may also be disclosed or claimed.

Abstract: A receiving method and apparatus is disclosed. The method comprising steps of: receiving a plurality of data according to a symbol clock signal, and reading out the plurality of data according to a first clock signal and generating a water level; receiving a second clock signal so as to generate a third clock signal, and adjusting the speed of the third clock signal according to the water level; determining a sampling frequency of the plurality of data according to a data amount of the plurality of data during a unit time period or parameters of the plurality of data; and dividing the third clock signal by a dividing value or multiplying the third clock signal by a multiplying value so as to obtain the first clock signal and adjust the water level by a clock generator.

Abstract: According to one embodiment, a clock generating circuit includes first and second current generating circuits, first and second voltage generating circuits, first and second comparing circuits, a clock output circuit, a control circuit. The first current generating circuit is configured to generate a first current. The first voltage generating circuit is configured to generate a first voltage which increases or decreases according to a phase of a clock signal as time advances by the first current. The first comparing circuit is configured to compare the first voltage with a first threshold voltage to generate a first comparison result. The second current generating circuit is configured to generate a second current. The second comparing circuit is configured to compare the second voltage with a second threshold voltage to generate a second comparison result.

Abstract: A synchronous signal generating circuit. The synchronous signal generating circuit includes a delay locked loop (DLL), an emulator and a multiplexer. The DLL is operative to delay a reference clock signal according to a count value to generate a first output clock signal. The count value is generated according to phase difference between the first output clock signal and the reference clock signal. The emulator is operative to provide a function of the DLL and includes a programmable delay line which is operative to receive the reference clock signal and a reference count value, wherein the reference clock signal is delayed according to the reference count value to generate a second output clock signal. The multiplexer is operative to receive the first and second output clock signal and selectively output the first or second output clock signal. The first output clock signal is outputted in a first mode and the second output clock signal is outputted in a second mode.

Abstract: Clock switch-over circuits and methods provide clock signals to clock routing networks. According to one embodiment, a multiplexer selects between a first clock signal and a second clock signal in response to a switch select signal received from a control circuit. A storage circuit stores an enable signal in response to an output clock signal of the multiplexer. A logic circuit transmits the output clock signal of the multiplexer to a clock routing network in response to the enable signal from the storage circuit. At least one signal is transmitted from the clock switch-over circuit to the control circuit.

Abstract: An apparatus for interleaved phase shift clock synchronization includes a master clock generator and at least one slave clock generator. The master clock generator provides a ramp signal or reset signal for each slave clock generator to generate a clock synchronized with the clock of the master clock generator, and the master and slave clock generators have different reference voltages for generating clocks. Therefore, the clocks generated will be synchronized and interleaved phase with each other.

Abstract: The present invention relates to a method and an apparatus, during a phase switching process, for choosing all of outputted phases upon the clock phases devoid of phase switching so as to avoid glitches during clock switching. Compared with the conventional approach for removing glitches by controlling a clock switching sequence, an improvement of a phase rotator is further disclosed in the present invention, which eliminates the glitches of the outputted phase clock so as to realize a glitch-less phase switching in a phase interpolation circuit.

Abstract: An apparatus for processing signals, in particular physiological measuring signals, wherein the apparatus is provided with different channels with signal inputs (1) for receiving input signals, which input signals each comprise a specific signal component and a signal component common to all input signals, wherein each channel is provided with an impedance transforming input amplifier (3), wherein the apparatus is configured for supplying to the non-inverting input of each input amplifier (3) a respective input signal and, to the inverting input an analogue reference signal common to all channels, wherein the apparatus is provided with a digital signal processor (10) and one more or analogue-digital converters (5) for supplying the signals provided by the input amplifiers (3) to the digital signal processor (10), wherein the signal processor (10) is designed for converting the signals received from the one or more analogue digital converters (5) into one or more output signals.

Abstract: Methods, systems, and apparatus can provide a multichannel interpolator while optimizing circuitry reuse.

Abstract: An internal clock frequency control circuit of a semiconductor memory apparatus includes a mode register set configured to receive a mode register set control signal and output a mode register set signal; a delay unit configured to generate an enable signal when a predetermined cycle has elapsed after the mode register set signal was activated; a division command decoder configured to receive and decode a synchronization command to generate a division start signal when the enable signal is activated; and a division selection unit configured to receive an input clock having a first frequency and output a selection clock having a second frequency, wherein a value of the second frequency is substantially the same as the first frequency or lower than the first frequency depending on a level of the division start signal.

Abstract: Provided is a receiving apparatus that receives a data signal and a clock signal indicating a reference timing to acquire the data signal. The receiving apparatus includes a multi-strobe generating section that generates, based on a pulse of the recovered clock, a plurality of strobes of which phases are different from each other, a first detecting section that detects a position of an edge of the clock signal relative to the strobes based on values of the clock signal that are acquired at respective timings of the strobe, a first adjusting section that adjusts a phase of the recovered clock according to the edge position of the clock signal, and a second adjusting section that adjusts the timing to acquire the data signal according to a phase adjustment amount of the recovered clock made by the first adjusting section.

Abstract: A multiplexer (MUX) circuit with balanced select line loading is provided. The MUX circuit includes a plurality of 2:1 MUX units coupled together in a multistage cascading arrangement, along with a selection module coupled to the MUX units. The MUX units are arranged in an initial MUX stage, at least one intermediate MUX stage coupled to and following the initial MUX stage, and a final MUX stage coupled to and following the at least one intermediate MUX stage. Each MUX unit is controlled with a respective select bit input value provided by the selection module. The selection module controls the operation of the MUX units in the initial MUX stage with a first plurality of different select bits, controls the operation of the MUX units in the at least one intermediate MUX stage with a second plurality of different select bits, and controls the operation of the final MUX stage with a devoted select bit.

Abstract: A clock frequency of a clock signal used by a processor may be temporarily reduced to compensate for voltage droops in the power supply to the processor. A device may include a multiplexer to receive a group of phase shifted versions of the clock signal and to output one of the group of phase shifted versions of the clock signal as an output clock signal. A control component may receive the output clock signal from the multiplexer and a voltage droop event signal indicating whether a voltage droop event is occurring in a power supply. The control component may control, in response to the voltage droop event signal indicating the occurrence of the voltage droop event, the multiplexer to iteratively select the group of phase shifted versions of the clock signal to reduce the frequency of the output clock signal.

Abstract: A method for balancing clock signals in an IC layout includes obtaining a data-flow information of the IC, selecting a first data-flow according to the dataflow information, and synchronizing a first clock signal from a first register and a second clock signal from a second register involved in the first data-flow. The data processed by the first register is directly transmitted to the second register or transmitted through a combinational logic circuit to the second register. The first data-flow is not related to other data-flows included in the data-flow information.

Abstract: Systems and methods are disclosed for precise generation of phase variation in digital signals. The disclosed signal generation embodiments generate a pattern of information bits that represents a digital signal with desired phase variations and transmit this digital pattern at high speed utilizing a serializer to generate a high speed bit stream. The high speed bit stream can be used to generate one or more digital signals, such as clock signals, having desired rates and desired phase variations. In certain embodiments, the desired phase variation can be introduced into the resulting digital signal by removing and/or inserting bits in a digital pattern thereby moving logic transitions (e.g., rising edge transitions, falling edge transitions) as desired within the resulting digital signal. In addition to clock signals, the resulting digital signals generated can be control signals, data signals and/or any other desired digital signal.

Abstract: A method and apparatus for providing system clock failover using a one-shot circuit are disclosed. A process, in one embodiment, is able to detect a clock failure using a one-shot circuit, wherein the clock signals are generated by a first clock circuit. Upon generating a switching signal in response to the clock failure, a system reset signal is asserted for a predefined time period in accordance with the clock failure. After switching a second clock circuit to replace the first clock circuit, the process is capable of resuming the clock signals via the second clock circuit.

Abstract: Phase mixers, clock signal generators, memories and methods for providing an output signal having a phase relative to the phase difference of input clock signals are disclosed. One such phase mixer includes a phase mixer circuit having inputs and an output. The phase mixer is configured to receive a plurality of input clock signals and generate an output clock signal at the output having a phase relative to the plurality of input clock signals. The phase mixer further includes an adjustment circuit coupled to the phase mixer circuit. In some phase mixers, a control circuit coupled to the phase mixer circuit and the adjustment circuit is included. The control circuit is configured to generate a control signal based on the input signals to adjust an electrical load-to-drive ratio of the phase mixer.

Abstract: A clock generation circuit, includes a first current source, a resistor connected to the first current source, a second current source, a first demux circuit connected to the second current source, a second demux circuit connected to the second current source, a capacitor connected to the first demux circuit and the second demux circuit, a first comparator connected to the first current source and the capacitor, a second comparator connected to the first current source and the capacitor, and a RS trigger connected both to the first comparator and the second comparator. The present invention has simple structure, small process variation, and lower cost, and is able to improve the accuracy of the clock with maximum possibility.

Abstract: A clock system includes a clock signal generating circuit and a controlling circuit. The clock signal generating circuit is used for generating a primary clock signal and a reference clock signal both derived from an oscillating signal of the clock signal generating circuit. The controlling circuit is coupled to the clock signal generating circuit and used for receiving the primary clock signal under a normal mode and compensating timing information generated from the primary clock signal according to the reference clock signal when the clock system exits a power saving mode. The primary clock signal is de-activated when the clock system enters the power saving mode and is activated when the clock system exits the power saving mode. The clock system can keep a continue clock for system to use when the primary clock signal is gated or power saving mode is entered.

Abstract: A flag signal generation circuit includes a first periodic signal detection unit, a second periodic signal detection unit, and a flag signal output unit. The first periodic signal detection unit is configured to detect a change in a level of a first periodic signal and generate a first detection signal. The second periodic signal detection unit is configured to detect a change in a level of a second periodic signal and generate a second detection signal. The flag signal output unit is configured to generate a pre-flag signal from the first and second detection signals, buffer the pre-flag signal in response to a mode register read signal, and output the buffered pre-flag signal as a flag signal.

Abstract: A mixed-signal network for generating distributed electrical pulses includes a control device and one or more networked mixed-signal devices. The control device generates digital and analog outputs that are directly connected to, or daisy-chained between, the networked mixed-signal devices. Each mixed-signal device responds under certain input conditions by generating one or more electrical pulses with characteristics controllable by the control device.

Abstract: A router, for routing at least one input signal to at least one output, comprises at least one input module and at least one output module. Each of the input and output modules includes at least one clock selector circuit for selecting from among a first and second clock signal, and an oscillator signal, as a common output clock signal for the at least first router, based in part on whether at least one of the first and second clock signals has toggled. The clock selector circuit provides redundancy as well as distribution of clock signals among elements within each module.

Abstract: A method and circuit for generating a clock signal. A power factor correction circuit has n channels operating out of phase and independently. The circuit is able to generate a clock signal for each channel according to the current cycle duration of each channel.

Abstract: An audio reproducing apparatus includes a power supply, an amplifier, a speaker, and a controller. The power supply is for supplying a voltage. The amplifier is for receiving the voltage and audio signals, amplifying the audio signals, and outputting amplified audio signals. The speaker is for reproducing sound after receiving the amplified audio signals. The controller is for receiving the voltage and generating a control signal to enable the amplifier. The controller includes a generator and a delay unit. The generator is for receiving the voltage and generating the control signal. The delay unit is for delaying the time of transferring the voltage from the power supply to the generator.

Abstract: A clock synchronization system and method avoids output clock jitter at high frequencies and also achieves a smooth phase transition at a boundary of coarse and fine delays. The system may use a single coarse delay line configured to generate two intermediate clocks from an input reference clock and having a fixed phase difference therebetween. The coarse delay line may have a hierarchical or a non-hierarchical structure. A phase mixer receives these two intermediate clocks and generates a final output clock having a phase between phases of the intermediate clocks. The coarse shifting in the delay line at high clock frequencies does not affect the phase relationship between the intermediate clocks fed into the phase mixer. The output clock from the phase mixer is time synchronized with the input reference clock and does not exhibit any jitter or noise even at high clock frequency inputs.

Abstract: The invention provides display control circuits for Vacuum Fluorescent Displays (VFDs). The display control circuit controls a plurality of display units of the VFD and comprises an image signal generator generating a plurality of image signals, a clock signal generator generating a clock signal, and a plurality of control signal generators. Each control signal generator receives one of the image signals and the clock signal, generates a control signal for one of the display unit, and determines the duty cycle of the control signal according to the received image signal and the clock signal. The brightness of one display unit varies with the duty cycles of the corresponding control signal. The clock signal generator comprises a plurality of flip-flops coupled in series and a plurality of logic gates.

Abstract: Integrated circuits that support dual-edge clocking are provided. Integrated circuits may include phase-locked loops that generate square-wave clock signals. The clock signals may be provided from off-chip equipment through input-output pins. The clock signals may be routed through a clock distribution network to provide local clock signals to pulse generators that generate clock pulses on rising and falling clock edges. The pulse generators may generate clock pulses that are triggered by the rising and falling clock edges with a common pulse width for optimum performance. Duty cycle distortion introduced by the clock network may be minimized for optimum performance. Adaptive duty cycle distortion circuitry may be used to control the pull-up/pull-down drive strengths of the clock buffer so that the high clock phase of the local clock signals is approximately a half clock cycle.

Abstract: Methods and apparatus for a gray-coded phase rotating frequency divider. A phase selector is provided that includes two or more selectors, each selector configured to receive multiple clock phases and output a respective clock phase based on one or more selection bits that are part of a selection input, and a gray code generator configured to generate a gray coded output that forms the selection input so that when the gray coded output changes state only selection bits associated with a single selector change. A method includes grouping a plurality of clock phases into two or more groups, for each group, selecting a respective clock phase based on one or more selection bits that are part of a selection input, and generating a gray coded output that forms the selection input so that when the gray coded output changes state only selection bits associated with a single group change.

Abstract: An embodiment method of generating an output pulse stream comprises first pulse modulating a first multi-bit input term to generate a first one-bit pulse stream, using a bitwise logic AND to combine the first one-bit pulse stream and a second multi-bit term, thereby generating a multi-bit AND output, and second pulse modulating the multi-bit AND output to generate a one-bit output pulse stream representing a product of the first and second multi-bit input terms.

Abstract: Oscillator system and method thereof. The oscillator system includes a first voltage-to-current converter configured to receive a first voltage and generate a first current based on at least information associated with the first voltage, and a second voltage-to-current converter configured to receive a second voltage and generate a second current based on at least information associated with the second voltage. Additionally, the oscillator system further includes a current-mode N-bit digital-to-analog converter configured to receive at least the second current and a first clock signal and to generate a third current based on at least information associated with the second current and the first clock signal. N is a first integer. The first clock signal is associated with a first clock frequency corresponding to a first clock period. Moreover, the oscillator system further includes a current comparator coupled to the first voltage-to-current converter and the current-mode N-bit digital-to-analog converter.

Abstract: A flag signal generation circuit includes a first periodic signal detection unit, a second periodic signal detection unit, and a flag signal output unit. The first periodic signal detection unit is configured to detect a change in a level of a first periodic signal and generate a first detection signal. The second periodic signal detection unit is configured to detect a change in a level of a second periodic signal and generate a second detection signal. The flag signal output unit is configured to generate a pre-flag signal from the first and second detection signals, buffer the pre-flag signal in response to a mode register read signal, and output the buffered pre-flag signal as a flag signal.

Abstract: In a method for recovery of a clock from a received digital data stream and an apparatus for recovering a clock from a received digital data stream, phase-shifted clock signals are generated from a receiver's clock. After selecting one of the phase-shifted clock signals, two other phase-shifted clock signals are determined. Depending on sample values taken at rising/falling edges of the three selected phase-shifted clock signals, counter values are increased and compared. The selection of phase-shifted clock signals and the steps of sampling the input digital data stream, comparing the values and increasing counter values, if required, are repeatedly performed until the comparison result of the counter values indicates that one of the latter determined phase-shifted clock signals strobes the received digital data stream in the centre of a bit period.

Abstract: A semiconductor device includes a first signal generator that generates a plurality of second signals having a delay relative to a first signal and having states that change at different timings. A second signal generator generates a third signal having a delay relative to the first signal. A detector detects a delay amount based on the states of the second signals when a state of the third signal changes. The first signal generator and the second signal generator are different from each other in an amount of change in delay relative to a change in an operating state.