Abstract: A memory clock signal is generated in response to a reference clock signal and a clock enable signal. The memory clock signal with a frequency identical to that of the reference clock signal is generated during the clock enable signal is in an enabled state; and the memory clock signal with a reduced frequency is generated when the clock enable signal is changed from the enabled state to a disabled state. The generation of a memory clock signal is adaptive so as to save power.

Abstract: A frequency-locked clock generator includes a voltage-controlled oscillator (VCO), a frequency-to-current converter, a reference current source and a gain stage. The VCO generates an output signal. The frequency-to-current converter generates a converter current proportional to a frequency of the output signal. The reference current source generates a reference current. The gain stage generates a control signal based on a difference between the converter current and the reference current. The control signal is applied to the VCO to adjust the frequency of the output signal. Feedback forces the VCO to generate an output clock signal such that the corresponding current it produces (i.e., the converter current) is equal to the reference current. When in lock, the frequency of the output signal is determined by a time constant (or equivalent time constant) of the frequency-locked clock generator.

Abstract: A pulse generator includes a pulse command register and a digital differential analyzer (DDA). The pulse command register includes a first register, a second register, and an adder. The first register receives and stores a pulse command from a CPU in an operating cycle. The second register receives and stores the pulse command shifted from the first register when the first register receives a second pulse command from the CPU in the operating cycle. The adder sums the pulse commands of the first register and the second register and the result is transmitted to the DDA. The DDA determines whether a pulse is to be generated after calculation according to the result from the adder of the pulse command register.

Abstract: The present invention describes a skew compensation circuit that can compensate for changes in signal skew in response to changes in external environments and processes. The skew compensation circuit includes a controller for outputting a control signal according to whether an external power supply is supplied and its operation mode. The skew compensation circuit also includes a signal output unit which selects either a normal path or a skew reduction path according to the control signal and outputs an input signal through the selected path.

Abstract: A method for generating a modulated carrier signal with reduced bit error rates based on a plurality of data symbols. A plurality of data symbols are received, and a digital input signal is generated based on the plurality of data symbols. The digital input signal are filtered to produce a digital output signal including a phase characteristic. The phase characteristic of the digital output signal remains close to the desired symbol phase for substantial portion of the symbol period. A carrier signal is modulated using the digital output signal to produce the modulated carrier signal.

Abstract: A method for generating a wide range of clock rates from a single clock. A delta is generated from a first clock signal and a second clock signal. An accumulative offset is generated from adding the delta to a previous accumulative offset for each clock period of the first clock signal. Whenever an overflow is encountered, the value of the accumulative offset is truncated. The second clock signal is interpolated between adjacent values.

Abstract: The disclosure includes a latch structure and self-adjusting pulse generator using the latch. In an embodiment, the system includes a first latch and a pulse generator coupled to provide a timing signal to the first latch. The pulse generator includes a second latch that has characteristics matching the first latch.

Abstract: A pulse generating circuit includes a starting circuit which generates m (two or larger integer) starting signals at predetermined time intervals based on a generation starting signal, and m pulse wave generating sub circuits which have the same characteristics and generate pulse waves having pulse width Pw for n cycles (n: 1 or larger integer) based on the respective m starting signals.

Abstract: A programmable clock generator circuit receives control signals and a global clock and generates a pulsed data clock and a scan clock in response to gating signals. The clock generator has data clock and scan clock feed-forward paths and a single feedback path. Delay control signals program delay elements in the feedback path and logic gates reshape and generate a feedback clock signal. The global clock and the feedback clock signal are combined to generates a pulsed local clock signal. A scan clock feed-forward circuit receives the local clock and generates the scan clock. A data clock feed-forward circuit receives the local clock and generates the data clock with a logic controlled delay relative to the local clock signal. The feedback clock is generated with controlled delay thereby modifying the pulse width of the data and scan clocks independent of the controlled delay of the data clock feed-forward path.

Abstract: Disclosed herein is a digital system that includes a distribution network to carry a reference clock, and a circuit domain coupled to the distribution network to receive the reference clock for synchronous operation in accordance with the reference clock. The circuit domain includes a clock generator driven by the reference clock to generate a resonant clock signal, an input port to receive a control signal, and a gate coupled to the input port to discontinue application of the resonant clock signal within the circuit domain based on the control signal.

Abstract: The present disclosure is an apparatus for generating a decreasing delay with increasing input voltage to a predetermined voltage value at which point the delay may remain constant. The apparatus may include a circuit comprising a voltage regulator receiving an input voltage and two paths of inverters. At least two paths of inverters may be coupled to an input signal, the input signal may be low voltage (e.g. 0) or high voltage (e.g. 1). A first path may be referenced to a reference voltage while the second path may be referenced to the input voltage. The apparatus may include logic gates for receiving the output of each of the first path of inverters and the output of the second path of inverters to generate a desired output. As the input voltage increases, delay of the apparatus may decrease until the input voltage is approximately the same voltage as the reference voltage, at which the delay may remain constant.

Abstract: There are provided, in a clock generator for generating a plurality of output clock signals, an apparatus and method for synchronizing the clock generator to an input reference clock in the presence of a jittery input clock provided to the clock generator from a PLL. The clock generator and the PLL each have a divider with the same ratio. The apparatus includes a synchronizer (205) and a state machine (210). The synchronizer receives the input reference clock and the jittery input clock, and generates there from a synchronized input clock signal with respect to the jittery input clock. The state machine receives the synchronized input clock signal and the jittery input clock, synchronizes with the synchronized input clock signal using the jittery input clock, and abstains from a re-synchronizing operation when the jittery input clock has a jitter of up to a pre-defined maximum number of clock widths.

Abstract: A clock control circuit includes a first signal generation block for outputting a first internal clock signal, which is enabled after delay of a first time from a rising edge of a first input clock signal and has a high level pulse width shorter by a second time than a high level pulse width of the first input clock signal, and a second signal generation block for outputting a second internal clock signal, which is enabled after delay of the first time from a rising edge of a second input clock signal and has a high level pulse width shorter by the second time than a high level pulse width of the second input clock signal.

Abstract: A square wave generator includes a sawtooth wave generator and a convertor. The sawtooth wave generator generates a sawtooth wave. The convertor generates a square wave based on the sawtooth wave. The sawtooth wave generator includes a capacitor and a switching unit connected parallel to each other. A first terminal of the capacitor is electrically coupled to a power source and the convertor, and a second terminal of the capacitor is grounded. When a voltage drop on the capacitor equals to or is greater than a first threshold voltage, the switching unit closes and grounds the first terminal of the capacitor, so that the capacitor discharges rapidly.

Abstract: A clock pulse generating circuit includes a pulse generator, a clock regulator, and a pre-driver. The pulse generator is configured to vary pulse widths of a rising clock signal and a falling clock signal. The clock regulator is configured to regulate output signals of the pulse generator to prevent an overlap and a duty drop of the output signals of the pulse generator. The pre-driver is configured to output data driving signals according to output signals of the clock regulator.

Abstract: A circuit to test phase linearity of a phase synthesizer, which synthesizes an output clock having a phase corresponding to a digital phase value input to the phase synthesizer. A digital counter provides the digital phase value to the phase synthesizer. The digital counter receives a counter clock synchronized with an input clock. The digital phase value is stepped by the digital counter, thereby shifting the frequency of the output clock. The output clock is analyzed with respect to phase linearity of the phase synthesizer to produce a phase linearity analysis output.

Abstract: A computer implemented method for designing a spectral-spatial pulse for exciting at least one passband and minimally exciting at least one stopband is provided. A uniform shaped spectral envelope is generated. For a plurality of kz?0, kz dependent weights for a spectral envelope that approximate a kz=0 envelope and provides the at least one passband and the at least one stopband for each of the plurality of kz?0 is generated.

Abstract: In an embodiment, a memory device comprises a clock generating unit being configured to generate a read clock signal, the clock generating unit being connected to a first clock signal contact configured to send the read clock signal, and the clock generating unit being connected to data signal contacts being configured to send data signals, the memory device being configured to send the data signals in a phase and frequency accurate (source synchronous) manner with regard to the read clock signal.

Abstract: A signal generating circuit includes an input stage delay circuit which can switch a state of outputting a reference clock and a state of outputting a signal delaying the reference clock by a first time which is shorter than one cycle of the reference clock, a control section including a gate circuit holding the output of the input stage delay circuit for a second time which is shorter than one cycle of the reference clock from a point at which the output of the input stage delay circuit is changed to output a signal corresponding to the output of the gate circuit, and an output stage delay circuit outputting a signal delaying the output signal of the control section by the second time, in which the input stage delay circuit switches an output state in response to change of the output signal of the control section.

Abstract: A multi-phase signal generators and methods for generating multi-phase signals are described. In one embodiment, a clock generator generates quadrature signals including those having 90, 180, 270 and 360 degrees phase difference with a first signal. The rising edge of an intermediate signal is compared with the rising edges of two of the other signals to generate an UP and DN pulse signal, respectively. The UP and DN signals are used to adjust the delay of a delay line producing the signals to synchronize the signals. In some embodiments, a reset signal generator is used to truncate the UP or DN signal pulse.

Abstract: A delay circuit has a fixed delay path at a lower voltage level, a level converter, and an adjustable delay path at a higher voltage level. The fixed delay path includes an inverter chain, and the adjustable delay path includes serially-connected delay elements selectively connected to the circuit output. In an application for a local clock buffer of a static, random-access memory (SRAM), the lower voltage level is that of the local clock buffer, and the higher voltage level is that of the SRAM. These voltages may vary in response to dynamic voltage scaling, requiring re-calibration of the adjustable delay path. The adjustable delay path may be calibrated by progressively increasing the read access time of the SRAM array until a contemporaneous read operation returns the correct output, or by using a replica SRAM path to simulate variations in delay with changes in voltage supply.

Abstract: A method for operating a data storage medium when changing from an operating mode to a directly subsequent power-saving quiescent mode, where the operating mode effects a transmission delay for the last item of information which is to be transmitted, so that immediately after the last item of information which is to be transmitted has been transmitted the quiescent mode is activated and the maximum permissible power consumption is observed.

Abstract: Methods and apparatus provide for automated synthesis of an integrated circuit whose voltage is varied during operation (also known as dynamic voltage and frequency scaling or DVFS). The automation may include estimating technology parameters from timing libraries, and determining a translation factor that can be used in estimating path delays for an arbitrary voltage from path delays at another voltage. The automation may also include estimating a relative difficulty to synthesize a design for meeting sets of timing constraints specified at different operating voltages and frequencies by assigning one of the constraints a common base value among all the sets, translating the other constraint to maintain equivalency of synthesis difficulty, comparing the resulting equivalent constraints to identify a hardest-to-synthesis constraint set, and using that constraint set as a goal for a first synthesis of the circuit.

Abstract: A device and a method for generating a output clock signal having a output cycle, the method includes: (i) adjusting a delay of an adjustable ring oscillator to provide a high frequency clock signal having a short cycle so that the output cycle substantially equals a sum of integer multiples of a sleep cycle and integer multiplies of the short cycle; wherein the output cycle differs from any integer multiples of the sleep cycle; wherein the sleep cycle characterizes a sleep clock signal that is generated by a low frequency sleep clock; wherein the short cycle is shorter than the sleep cycle; (ii) counting short cycles and sleep cycles; and (iii) generating, during a sleep mode, in response to the counting and to a predefined counting pattern, the first clock signal; wherein the generating includes activating the adjustable ring oscillator only during a portion of a single sleep cycle per each output cycle.

Abstract: A VCO includes a reference current module and a clock signal generating module. The reference current module generates a reference current according to a reference voltage. The clock signal generating module generates a clock signal according to the reference current. The reference current module utilizes the negative feed-back mechanism to keep the generated reference current at the predetermined size without being changed with the variation of the process and the bias source.

Abstract: An inverter circuit using FETs which do not cause a fluctuation in gate threshold voltage Vth is provided. The inverter circuit has a load transistor and a driving transistor which is serially connected to the load transistor and supplies a load current to the load transistor in accordance with an input signal. The load transistor has at least two FETs which are connected in parallel and have controlled terminals. A driving part alternately turns on the FETs through the controlled terminals.

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: The present invention discloses a sense amplifier control circuit which controls the sense amplifier. A sense amplifier control circuit comprises a voltage comparing unit outputting delay control signals having a value corresponding to each of divided voltages obtained by dividing a potential of a power supply voltage and a pull-up control signal generating unit outputting an overdrive control signal and a pull-up control signal by an active signal and changing an enable pulse width of the overdrive control signal in response to the delay control signals, whereby it is possible to reduce current consumption caused by unnecessary overdrive operation and prevent a potential drop of the power supply voltage and thus provide operational stability of the semiconductor memory device by providing the overdrive control signal of which the enable pulse width is controlled in response to the potential of the power supply voltage.

Abstract: A circuit for providing a delayed clock signal to a synchronous memory controller controlling a synchronous memory device comprises logic delay circuitry for performing synchronous memory device read access, the logic delay circuitry generating delay interval information. A programmable delay line receives a clock signal and the delay interval information, the programmable delay line delaying the clock signal by the delay interval. A 2-input XOR gate receives both the clock signal and the output of the programmable delay line, an output of the XOR gate providing a delayed 2× clock signal.

Abstract: A memory device includes a clock buffer circuit. The clock buffer circuit includes a cross-coupled logic circuit. The cross-coupled logic circuit has at least two logic gates in which an output of at least one of the logic gates is coupled to an input of at least one of the logic gates. The cross-coupled logic circuit is coupled to an input for accepting a clock signal. The memory device also includes a clock driver operable to generate a clock signal from the output of the cross-coupled logic circuit. A feedback loop from the clock signal to the cross-coupled logic circuit controls the cross-coupled logic circuit. A buffer circuit including a tri-state inverter is coupled to the clock signal to maintain the clock signal while avoiding contention with the clock generator. The memory device is enabled by a chip select signal.

Abstract: A multiphase clock generator circuit for generating a plurality of output clock pulses that differ in phase on the basis of a reference clock pulse, has first and second divider circuits for dividing first and second reference clock pulses that differ in phase to generate output clock pulses, and a switch for forming an intermittent short between predetermined nodes of the first and second divider circuits, wherein the switch forms a short between the predetermined nodes with timing in which the predetermined nodes are brought to the same level in a normal operating state.

Abstract: A pulse signal generator includes a period setting unit that receives a period set signal including an information indicative of a pulse period, and that outputs a period control signal controlling the pulse period, a duty ratio setting unit that receives a duty ratio set signal including an information indicative of a duty ratio of a pulse, that receives a signal including the pulse period set in the period setting unit, and that generates a duty ratio control signal controlling the duty ratio of the pulse on a basis of the pulse period and the duty ratio set signal, and a pulse generation unit that generates a pulse signal including the pulse period and the duty ratio of the pulse on a basis of the period control signal and the duty ratio control signal.

Abstract: A pulse generator includes a pulse command register and a digital differential analyzer (DDA). The pulse command register includes a first register, a second register, and an adder. The first register receives and stores a pulse command from a CPU in an operating cycle. The second register receives and stores the pulse command shifted from the first register when the first register receives a second pulse command from the CPU in the operating cycle. The adder sums the pulse commands of the first register and the second register and the result is transmitted to the DDA. The DDA determines whether a pulse is to be generated after calculation according to the result from the adder of the pulse command register.

Abstract: A method for generating a clock signal and a device having clock generating capabilities, the device includes: (i) a first divider, adapted to receive an input clock signal and divide the input clock signal to provide a first clock signal; (ii) a second divider, adapted to receive an input clock signal and divide the input clock signal to provide a second clock signal; wherein the first clock signal is phase shifted in relation to the second clock signal by half an input clock cycle; wherein a delay period of the first divider substantially equals a delay period of the second divider over a large range of delay affecting parameter values; (iii) a reconstruction circuit, connected to the first and second divider circuits, adapted to receive the first and second clock signals and apply a logical operation on the first and second clock signals to provide a reconstructed clock signal; and (iv) a selection circuit, connected to the first divider, second divider and reconstruction circuit, adapted to output an outp

Abstract: A charge pump control circuit that four main parts: a clock control circuit; a clock switch and driver circuit; a pump stage; and a dynamic load control circuit. The clock control circuit has a dynamic load that is controlled by the dynamic load control circuit. When the charge pump control circuit is enabled, the dynamic capacitive load is applied which incorporates a delay allowing the high frequency clock to control the pump stage and quickly charge the output to the desired boosted voltage. This provides a very fast boosted output voltage during a startup condition. Once the desired output voltage is realized, the dynamic capacitive load is disabled and the low frequency clock takes over the operation. During each low frequency clock cycle, the high frequency clock is enabled for several cycles per cycle of the low frequency clock.

Abstract: A delay-lock loop receives an input clock signal from the output of a programmable divider that receives a reference clock signal. The delay-lock loop includes a voltage-controlled delay line generating a plurality of delayed clock signals having different phases. A plurality of the delayed clock signals are combined to generate a plurality of output signals. During an initialization period, an initialization circuit sets the delay of the delay line to a minimum delay value and then compares this delay value to the period of the input clock signal. Based on this comparison, the initialization circuit programs the programmable divider and adjusts the number of delayed clock signals combined to generate the output signals. More specifically, as the frequency of the reference clock signal increases, the divider is programmed to divide by a greater number, and a larger number of delay clock signals are combined to generate the output signals.

Abstract: In a semiconductor device capable of radio communication, a stable clock signal is generated even if a reference clock signal for generating a clock signal has varied frequencies in each cycle. A clock signal generation circuit includes an edge detection circuit that detects an edge of an input signal and generates a synchronization signal, a reference clock signal generation circuit that generates a clock signal which functions as reference, a counter circuit that counts the number of edges of rise of the reference clock signal in accordance with the synchronization signal, a duty ratio selection circuit that selects a duty ratio of a clock signal from a count value, and a frequency division circuit that generates the clock signal having the selected duty ratio.

Abstract: Integrated circuit and programmable delay. One embodiment provides an integrated circuit including a programmable delay element having a plurality of single delay cells. The delay cells include a first input and a second input and a first output. The delay cells are arranged to form a chain such that the first output of a preceding delay cell is coupled to the second input of a successive delay cell. The first inputs of any delay cells are configured to receive an input signal to be delayed. The delay cells out of the plurality of delay cells is configured to constitute a starting point of a signal path including any of the delay cells arranged downstream of the starting point. The first output of the last delay cell in the chain forms an output of the programmable delay element.

Abstract: A system and method that use a first clock to digitally generate a second clock, wherein the ratio of the frequency of the first clock to the frequency of the second clock is a non-integer. Circuitry may be used to ensure that the first clock, or input clock, has a frequency at least equal to the highest of the desired output frequencies. The input clock may be used to generate several output clocks with different frequencies. If one of the output clocks has the same frequency as the input clock, the circuitry can be bypassed. The different clocks may be used to drive parts of a system, each of which may require a different frequency.

Abstract: Embodiments of the invention are generally directed to systems, methods, and apparatuses for the direct duty cycle calibration of a receiver clock. In some embodiments, an integrated circuit includes a receive (RX) data path, a RX clock path, and a control path. In some embodiments, the control path uses RX latches, a majority detector, and digital duty cycle control logic to calibrate the duty cycle of the clock signal. Other embodiments are described and claimed.

Abstract: A clock pulse generating circuit includes a pulse generator, a clock regulator, and a pre-driver. The pulse generator is configured to vary pulse widths of a rising clock signal and a falling clock signal. The clock regulator is configured to regulate output signals of the pulse generator to prevent an overlap and a duty drop of the output signals of the pulse generator. The pre-driver is configured to output data driving signals according to output signals of the clock regulator.

Abstract: A time-to-digital converter includes low and high resolution time-to-digital converters for providing both high resolution and wide measurement range. The low resolution time-to-digital converter measures a time difference between first and second signals with a first quantization step. The high resolution time-to-digital converter measures the time difference between the first and second signals with a second quantization step that is smaller than the first quantization step. The low resolution time-to-digital converter has a wider measurement range than the high resolution time-to-digital converter.

Abstract: A clockless transmission system includes display controller 101 and display driver 106. Display controller 101 includes data transmission circuit 102 configured to output general data obtained by multiplexing a clock by coding serialized pixel data for each pixel data during a data communication interval and also to output a predetermined control signal during a blanking interval. Display driver 106 includes clock and data recovery circuit 107 configured to output the pixel data from the general data transferred from the display controller and to increase a loop gain of a feedback loop in clock recovery such that the loop gain is larger than that when the general data is received, according to control data of the control signal, to recover and output a clock, and display driving circuit 109 configured to output a signal for driving a display based on the pixel data and the recovered clock.

Abstract: A data communications system is disclosed. The data communications system comprises two clock domains. Each of the clock domains are coupled to receive a source clock signal. The first clock domain includes a first clock signal and the second clock domain includes a second clock signal, each of the first clock signal and the second clock signal are derived from the source clock signal. The first clock signal has a frequency which is different from that of the second clock signal, and which is not an integer multiple of the frequency of the second clock signal. The first clock domain includes circuitry which is configured to generate both the first clock signal and a reference clock signal derived from the source clock signal.

Abstract: Systems and methods are disclosed herein to provide improved clock, delay, and skew techniques. For example, in accordance with an embodiment of the present invention, an integrated circuit includes a clock generator to provide a bias signal and a clock signal, with control logic providing a delay control signal based on the bias signal and a multi-bit control signal. A clock skew circuit provides a delay to the clock signal based on the delay control signal provided by the control signal. Memory coupled to the control logic provides the multi-bit control signal.

Abstract: A semiconductor integrated circuit includes a pulse control register configured to hold an assigned code with a smaller number of bits than that of a pulse control pattern used to control an oscillation output of an oscillator, a code conversion unit configured to convert the assigned code held by the pulse control register into the pulse control pattern, and a pulse control unit configured to generate the test pulses by controlling pulses of the oscillation output of the oscillator based on the pulse control pattern resulting from the conversion by the code conversion unit.

Abstract: A circuit for generating a clock of a semiconductor memory apparatus is provided. A reference voltage generator is configured to generate a reference voltage. A reference current generator is configured to generate a reference current that has a constant current value regardless of a change in temperature. An oscillator is configured to receive the reference voltage and the reference current to generate a clock that has constant frequency.

Abstract: Generating an output pulse signal (Y), which has an output signal period (Ty), which is divided by a magnitude transition into a leading part (LP) and a trailing part (TP). During each output signal period (Ty) altering means (27 to 36) determine in a coarse and fine way a duration (TLP, TTP) of one or both of said output signal period parts (LP, TP) by using a clock signal (Cx) of different clock cycle durations (TCx0, TCx1, TCx2), dependent on a value of a first digital number (D1) and a value of second, less significant digital number (D3, D5), respectively.

Abstract: A spread-spectrum clock generator is provided, which includes a modulation module and a voltage-controlled delay line (VCDL). The modulation module provides a control voltage. The VCDL is coupled to the modulation module and is configured for modulating the frequency of an input clock signal according to the control voltage, so as to output an output clock signal. The modulation profile of the output clock signal is a periodic function of time.

Abstract: A device and a method for generating a output clock signal having a output cycle, the method includes: (i) adjusting a delay of an adjustable ring oscillator to provide a high frequency clock signal having a short cycle so that the output cycle substantially equals a sum of integer multiples of a sleep cycle and integer multiplies of the short cycle; wherein the output cycle differs from any integer multiples of the sleep cycle; wherein the sleep cycle characterizes a sleep clock signal that is generated by a low frequency sleep clock; wherein the short cycle is shorter than the sleep cycle; (ii) counting short cycles and sleep cycles; and (iii) generating, during a sleep mode, in response to the counting and to a predefined counting pattern, the first clock signal; wherein the generating includes activating the adjustable ring oscillator only during a portion of a single sleep cycle per each output cycle.