Abstract: A multiple-phase clock generator includes at least one stage of dividers. A clock signal is supplied as a first stage clock input to dividers in a first stage of dividers. An N-th stage includes 2N dividers, where N is a positive integer number. Each divider in the first stage is configured to divide a first clock frequency of the first stage clock input by 2 to provide a first stage output. Each divider in the N-th stage is configured to divide an N-th clock frequency of an N-th stage clock input by 2 to provide an N-th stage output. The N-th stage outputs from the dividers in the N-th stage provide 2N-phase clock signals that are equally distributed with a same phase difference between adjacent phase clock signals.

Abstract: The present invention relates to a circuit arrangement (300) for generating non-overlapping and immune-to-1/f-noise signals as has been described. A break-before-make (BBM) circuit ensures that the differential I/Q signals (LO—0, LO—90, LO—180, LO—270), driving the transistors (M11, M12, M21, M22) of mixers (16A, 16B) in an RF receiver (200), are non-over-lapping for having at any time only one of these transistors turned on. The duty cycle of each driving signal is measured, and the difference (?) in the duty cycle corresponding to two subsequent LO phases is determined through a respective differential amplifier (38A-38D). Each differential amplifier is configured to have a current output (LT—0, LT—90, LT—180, LT—270), which is then fed back to the input of the input buffer (30A-30D) corresponding to the first LO phase in order to adjust its logic threshold (LT) level and make the difference (?) equal to zero.

Abstract: A linear phase detector includes an up/down pulse generator operating in response to received data signals and a recovered clock signal. The phase detector generates up and down pulses that have pulse widths proportional to the phase differences between transitions of the received data signals and edges of the recovered clock signal. By generating up and down pulses using a linear phase detector in proportion to a phase error, data signals are effectively recovered, even data signals with significant jitter.

Abstract: A structure for performing cross-chip communication with mesochronous clocks. The structure includes: a data delay line; a remote clock delay line; a structure that captures at least one value of a state of a delayed remote clock signal on the remote clock delay line; and a control that influences a delay associated with the data delay line and the remote clock delay line.

Abstract: A multiple-phase clock generator includes at least one stage of dividers. A clock signal is supplied as a first stage clock input to dividers in a first stage of dividers. An N-th stage includes 2N dividers, where N is a positive integer number. Each divider in the first stage is configured to divide a first clock frequency of the first stage clock input by 2 to provide a first stage output. Each divider in the N-th stage is configured to divide an N-th clock frequency of an N-th stage clock input by 2 to provide an N-th stage output. The N-th stage outputs from the dividers in the N-th stage provide 2N-phase clock signals that are equally distributed with a same phase difference between adjacent phase clock signals.

Abstract: A method for source synchronous communication. The method includes dynamically adjusting a delay that is applied to a data signal and a remote clock signal until a delayed remote clock signal is synchronized with a local clock signal, and capturing data from a delayed data signal associated with the delay in a local domain.

Abstract: An electronic circuit for distributing a clock signal to several clock destinations includes phase adjustment circuits for adjusting phase shifts of the clock at the respective one of the clock destinations responsive to a respective DC voltage feedback signal receive from the respective one of the clock destinations; phase detectors for detecting a phase shift of the clock signal at the respective one of the clock destinations according to a nearest neighbor clock destination; loop filters for generating and transmitting respective DC voltage feedback signals; current sources, each configured to receive the respective DC voltage feedback signal and output a respective current to a respective one of the phase adjustment circuits according to said respective DC voltage feedback signals to adjust the phase shift of the clock signal for the respective one of the clock destinations.

Abstract: A clock multiplying circuit includes: first and second inverters being ON/OFF-controlled by a positive- or negative-phase signal, respectively, of a first clock signal and including current source and current sync terminals; a capacitive element provided between output ends of the inverters; a current supplying unit increasing, if a frequency of the first clock signal increases, the control current and supplying the control current to the current source terminals of the inverters and outputting, from the current sync terminals of the inverters, a control current the same current amount as that of a control current to the current source terminal; a differential detecting unit receiving input of a potential difference signal between both electrodes of the capacitive element and generating a second clock signal having a phase difference of 90 degrees; and a multiplied-signal generating unit generating a double signal of the first clock signal on the basis of the clock signals.

Abstract: A multiphase clock generation circuit (111) for generating a multiphase clock signal, a phase subdivision unit (113) for shifting a phase of the multiphase clock signal output from the multiphase clock generation circuit (111), and a clock selection unit (114) for selecting one of clock signals output from the phase subdivision unit (113) are provided. A PLL circuit (120) for receiving an output from a frequency division circuit (115) is further provided. The phase shift carried out by the phase subdivision unit (113) and the selection of the clock signal carried out by the clock selection unit (114) are controlled by a frequency control unit (112) to switch SSC ON/OFF and to change the bandwidth of the PLL circuit (120).

Abstract: A DLL circuit includes a first delay adjusting circuit that adjusts an amount of delay of a frequency-divided signal CK1, a second delay adjusting circuit that adjusts an amount of delay of a frequency-divided signal CK2, a synthesizing circuit that synthesizes outputs of these delay adjusting circuits to generate an internal clock signal, and supplies the internal clock signal to a real path, a clock driver that receives the output of the first delay adjusting circuit and supplies the output to a replica path, and a clock driver that receives the output of the second delay adjusting circuit. These clock drivers have substantially the same circuit configuration. Accordingly, even when the power supply voltage fluctuates, influences of the fluctuations on the respective frequency-divided signals are almost equal. Thus, deterioration of the function of the DLL circuit due to fluctuations of the power supply voltage can be prevented.

Abstract: A circuit apparatus and method for generating multiphase clocks in a delay lock loop (DLL) at sub-picosecond granularity. The circuit and method of the invention involves locking a number of cycles M in an N stage DLL, e.g., M cycles, where M is an prime number, which results in clock edges in each cycle that are not located at the same phase locations in each of the M cycles. Any of the phase locations from any of the cycles can be used to generate a clock edge for all cycle in the system application. This requires a special technique to “lock” the DLL loop over a M cycle period instead of a one cycle period. The benefit is that it improves the clock placement granularity by a factor of M over the previous art.

Abstract: Provided is a multiphase clock generation circuit (1) including: a phase-locked loop circuit (10) for generating multiphase clock signals based on a reference clock signal; a frequency profile holding circuit (20) for holding a frequency profile of each of the multiphase clock signals, starting output of the frequency profile in response to a start signal, and for updating the frequency profile with a predetermined cycle based on the reference clock signal; and a clock selection circuit (30) for selecting a clock signal with an arbitrary phase from among the multiphase clock signals based on the frequency profile, and for feeding back the selected clock signal to the phase-locked loop circuit (10).

Abstract: In accordance with a preferred embodiment, a time-interleaved (or multi-phase) architecture is provided having individual control of a plurality of output signals or phases. The time-interleaved architecture may be implemented using a first set of delay cells such as those in a ring oscillator or a delay line device receiving overall control of its output signals by a global control signal. The global control signal may be issued by a phase-locked loop, delay-locked loop, or other like structure. A second set of delay cells is provided to further delay the output signals produced by the first set of delay cells. The second set of delay cells are controlled by individual control signals uniquely calibrated in accordance with a preferred embodiment of the invention to provide uniform (or substantially) uniform time spacing between output signals.

Abstract: The present invention is directed to a phase shifting arrangement for generating a set of mutually orthogonal signals. In one aspect, the invention provides a system that includes a phase shifting unit for receiving an input signal. The phase shifting unit includes a first phase shift circuit for generating a first output signal phase-shifted by a first amount with respect to the input signal, a second phase shift circuit for generating a second output signal phase-shifted by a second amount with respect to the input signal, and a third phase shift circuit for generating a third output signal phase-shifted by a third amount with respect to the input signal.

Abstract: A phase splitter. The splitter includes a transistor having a gate receiving an input signal, a drain and source outputting a first and second output signal with a first and second phase, respectively, a current source providing a current flowing from the drain to the source of the transistor, and a feedback tuning circuit receiving the first and second output signal, and tuning the current according to the first and second phase.

Abstract: The invention relates to a balanced circuit arrangement for converting an asymmetric analogous input signal (S1) into a symmetrical output signal (S2, S3). A first amplifier (2) is provided, whereby the non-inverting input thereof is connected to the analogous input signal (S1) and the output signal (S2) thereof is fed back to the inverting input thereof in a negative feedback. Moreover, a second amplifier (3) is provided, whereby the non-inverting input thereof is connected to ground, the inverting input thereof is connected to the output signal (S2) of the first amplifier (2) by means of a series resistor (R2) and the output signal (S3) thereof is fed back to the inverting input thereof in a negative feedback and by means of a negative feedback resistor (R1). The negative feedback resistor (R1) and the series resistor (R2) are provided with the same resistance value. The aim of the invention is to process higher maximum levels of the source signal and to suppress noises of the second amplifier.

Abstract: A system (50) has a shifting delay circuit (60) which provides a variable delay for delaying a source clock and a delay locked loop (DLL) (70) which includes a delay line (72) which provides a variable delay for delaying the source clock. The delay line (18) has its delay varied by a counter (74). The counter (74) is incremented in order to change the delay. The shifting delay circuit (60) is based on half periods of a reference clock (GCLK) which has a known relationship to the source clock. The total delay for the source clock is a combination of that provided by shifting delay circuit (60) and delay line (72). The delay line (72), which requires relatively large amounts of die area in an integrated circuit can be smaller in size due to the usage of shifting delay circuit (60).

Abstract: A circuit is designed with a delay circuit (300,301,500) coupled to receive a bias (256) and a reference signal (242). The delay circuit produces a series of phase signals (214). The phase signals are spaced apart in time in response to the bias. Each phase signal has a respective time after the reference signal. Each phase corresponds to logic states of a plurality of data signals. An encoder circuit (900,1100) is coupled to receive a first phase signal and a first plurality of data signals (212). The encoder circuit produces a first encoded data signal (220) at a time corresponding to the respective time of the first phase signal. A decoder circuit (600,800) is coupled to receive a second phase signal and a second encoded data signal (220) corresponding to the respective time of the second phase signal. The decoder circuit produces a second plurality of data signals (212) corresponding to the second phase signal.

Abstract: A circuit comprising an input circuit and an adjustable delay. The input circuit may be configured to generate a differential signal in response to a single ended signal. The adjustable delay may be configured (i) delay or not change a rising edge or (ii) delay or not change a falling edge of a first portion of the differential signal. A second adjustable delay may be configured (i) delay or not change a rising edge or (ii) delay or not change a falling edge of a second portion of the differential signal. The differential signal may be presented to an output buffer in a Universal Serial Bus device. The present invention may also include a squaring circuit that may be configured to improve the differential alignment between the first and second portions of the differential signal.

Abstract: A system (50) has a shifting delay circuit (60) which provides a variable delay for delaying a source clock and a delay locked loop (DLL) (70) which includes a delay line (72) which provides a variable delay for delaying the source clock. The delay line (18) has its delay varied by a counter (74). The counter (74) is incremented in order to change the delay. The shifting delay circuit (60) is based on half periods of a reference clock (GCLK) which has a known relationship to the source clock. The total delay for the source clock is a combination of that provided by shifting delay circuit (60) and delay line (72). The delay line (72), which requires relatively large amounts of die area in an integrated circuit can be smaller in size due to the usage of shifting delay circuit (60).

Abstract: A fractional period delay circuit to delay a clocking signal by a non-integer fraction of the period of the clocking signal is disclosed. The fractional period delay circuit has a first delay line connected to a master timing signal to delay the master clock to form the first timing signal. The fractional period delay circuit has plurality of adjustable delay lines. Each adjustable delay line is connected to the master timing signal to delay the master timing A delay adjustment input will modify the delay of the adjustable delay circuit. The fractional period delay circuit further has a plurality of phase difference detectors connected to the output of the first delay line and to the output of one of the plurality of adjustable delay lines. The phase difference detector will create a difference signal indicating a difference in phase between the first timing signal and one of the delayed timing signals. A plurality of sequence timing signals are created in a is timing sequence generator.

Abstract: An oscillating means having an oscillator outputs a reference clock, and a frequency-dividing means sequentially frequency-dividing the reference clock into a half frequency. A temperature correction data creating means detects a temperature, calculates logical delaying/advancing data for a temperature change, and outputs the logical delaying/advancing data in every predetermined period. A temperature correction data input means receives the delaying/advancing data outputted by the temperature correction data creating means and outputs the logical delaying/advancing data to a logical delaying/advancing means. The logical delaying/advancing means operates a state of the frequency-dividing means in every predetermined period on the basis of the set logical delaying/advancing data to control the period of the frequency-divided output signal of the frequency-dividing means so as to be coincident with a desired period.

Abstract: According to the present invention, when a semiconductor device is tested, a signal for test can be set in the semiconductor device at a desired timing. A second delay circuit of the present invention has the same structure as a first delay circuit in a phase lock loop, and receives a control voltage from the phase lock loop so as to generate a clock signal with a frequency according to the control voltage and to delay and output the clock signal. A second pulse generator generates two-phase clocks by using delayed signals generated by the second delay circuit. Switches are used for switching between a system clock output terminal during an actually active time and a system clock output terminal during testing.

Abstract: In an internal clock signal generation circuit, a plurality of internal clock signals of different phases are generated based on an external clock signal. The internal clock signals are synchronized with the external clock signal by a PPL circuit. The plurality of internal clock signals are respectively supplied to a plurality of internal circuit blocks. Since the phases of the generated internal clock signals are different the phases of the internal clock signals arriving at the internal circuit blocks can be matched even if delays of the signals between the internal clock signal generation circuit and the plurality of internal circuit blocks are different. Thus, clock skews between the plurality of internal clock signals can be reduced and the phase of the internal clock signal and the phase of the external clock signal can be synchronized.

Abstract: An error-limiting circuit for regulating the time required to bring the output signal of a control system such as a phase-locked loop device into conformance with a reference input signal. For a phase-locked loop system the error-limiting circuit is a phase-error-limiting circuit that provides for a gradual changing of the signal frequency of a voltage-controlled oscillator of the phase-locked loop device so that frequency synchronization of subsequent devices coupled to the phase-locked loop with the reference signal is ensured. The phase-error-limiting circuit forms part of the phase-frequency detector that is coupled to a charge pump that outputs current to a loop filter that in turn effectively controls the voltage-controlled oscillator. The phase-error-limiting circuit acts to assert or de-assert as required an error-correcting UP or DOWN signal to the charge pump.