Abstract: A method and apparatus is disclosed for adjusting at least one of a supply voltage and a clocking frequency applied to digital circuitry of a computing device, wherein the digital circuitry comprises a critical path circuit. A propagation delay frequency representing a propagation delay of the critical path circuit is generated, and a frequency error signal is generated representing a difference between a reference frequency and the propagation delay frequency. At least one of the supply voltage and the clocking frequency is adjusted in response to the frequency error signal.

Abstract: When a buffer is formed by using transistors having large element characteristic variations, the deviation of the timing between the input clock pulse and the reset pulse is likely to occur. When the deviation of the timing becomes larger, a malfunction is caused to occur, and an operation margin becomes smaller with respect to the variations of the element characteristics. In a timing generation circuit, which is formed on an insulating substrate and which has two TFFs (12, 13), for generating a dot clock DCK and a horizontal clock HCK whose frequencies are different in synchronization with a master clock MCK which is input external to the substrate, separate reset pulses drst and hrst are generated at a pulse generation circuit 15 with respect to the two TFFs (12, 13), and a resetting operation is performed at separate timings. Thus, a large operation margin can be ensured even when each circuit is formed by using TFTs having large element characteristic variations and a rough process rule.

Abstract: A timing generator capable of improving design efficiency by facilitating adaptation to change in design. The timing generator has work area 9 which outputs parameters in response to control data, and main core 12 to which the parameters are inputted. In the work area, V and H parameters are described. The main core consists of third comparator 11 for comparing a count value of V counter 10 with V parameter and outputting a first control pulse, first comparator 1 for comparing a count value of H counter 3 with H parameter and outputting a second control pulse, second comparator 4 for comparing a count value of high speed counter 8 with H parameter and outputting a third control pulse, first selector 2 for selecting the second control data or the third control data, and first JK flip flop 5 for generating a timing signal from output of the first selector.

Abstract: A clock controlling circuit and method for eliminating the delay difference in the entire clock propagation line. Circuit scale is reduced as compared to a case of using a PLL or DLL circuit. A timing averaging circuit 10 is fed with clocks from a position on a forward route 111 of a direction-reversed clock propagation path, adapted for being fed with input clocks at its one end, and from a position on a return route 112 corresponding to the position on the forward route 111. The timing difference between these clocks is averaged to output an averaged timing difference.

Abstract: A clock controlling circuit and method for eliminating the delay difference in the entire clock propagation line. Circuit scale is reduced as compared to a case of using a PLL or DLL circuit. A timing averaging circuit 10 is fed with clocks from a position on a forward route 111 of a direction-reversed clock propagation path, adapted for being fed with input clocks at its one end, and from a position on a return route 112 corresponding to the position on the forward route 111. The timing difference between these clocks is averaged to output an averaged timing difference.

Abstract: Described are methods and systems for distributing low-skew, predictably timed clock signals. A clock distribution network includes a plurality of dynamically adjustable clock buffers. A control circuit connected to each clock buffer controls the delays through the clock buffers in response to process, voltage, and temperature variations, and consequently maintains a relatively constant signal-propagation delay through the network. In one embodiment, each clock buffer includes skew-offset circuitry that adds to or subtracts from the PVT compensated delay values provided by the PVT control circuit to simplify clock skew minimization.

Abstract: The invention provides a clock delay arrangement accounting for the worst-case delay situation of data signals, which is independent of the layout and technology. It comprises a main clock line; two dummy clock lines, each arranged parallel to the main clock line, and the main clock line disposed between the two dummy clock lines; and a clock source coupled to the main clock line and the two dummy clock lines, adapted to drive said dummy clock lines in phase opposition with respect to the main clock line.

Abstract: A complementary digital signal generator circuit and method receives a periodic digital signal, such as a square wave, as an input and generates at the output complementary versions of the digital signal delayed by matching increments of delay with minimum skew at GHz frequencies. The digital signal is processed by inverters and interpolators which may be readily matched in size and functional characteristics by close proximity placement on integrated circuits. An inverted and first delayed version of the original digital signal is applied to both inputs of a first interpolator, to generate at the output of the interpolator the complement of the digital signal as delayed by the first delayed and the delay introduced by the interpolator. The inverted and first delayed digital signal is inverted and second delayed by a second matching inverter and applied as one input to a second interpolator. The second input of the second interpolator is the original digital signal.

Abstract: In integrated circuit (IC) devices, skew concerns between the clock pulses supplied to different latches hinder high speed operation. An IC device therefor includes a first clock processor means to generate a third clock pulse in response to first and second clock pulses with identical phase and frequency, a second clock processor means to generate a fifth clock pulse in response the third clock pulse and a fourth clock pulse with identical phase and frequency, and first and second latch groups each including a plurality of latches, in which the second clock pulse is generated via a buffer or divider from the third clock pulse, a fourth clock pulse is generated via a buffer or divider from the fifth clock pulse, and the third and fifth clock pulses are supplied to the first and second latch groups via a buffer, respectively.

Abstract: A clock generator circuit incorporates a sub-PTAT (proportional to absolute temperature) current source and a super-PTAT current source for generating bias currents for a voltage reference generator and charging currents for a voltage ramp generator. The clock generator circuit further includes a linear comparator coupled to receive one or more switching voltage reference signals and a voltage ramp signal and generate a switching output signal as the clock signal. The clock signal is coupled to a clock decoder to generate the desired clock signals having the desired phase. The functional blocks of the clock generator circuit of the present invention operate together to generate a highly frequency stable clock signal. In one embodiment, the linear comparator incorporates a dual-differential-input (dual-channel) instrumentation amplifier as the comparator input stage to generate clock signals having clock frequency errors that are minimized over process, temperature and power supply variations.

Abstract: A method and circuit for synchronizing an input clock signal with a plurality of internal clock signals in a multiple phase Pulse Width Modulation (PWM) switching power supply without using a Phase Locked Loop (PLL). A period of the input clock signal is measured by using a frequency to voltage converter. A reference capacitor charged by a constant current source is arranged to generate a reference voltage with a slope based on the period of the input clock signal. A change in the reference voltage across the reference capacitor is substantially inversely proportional to a frequency of the input clock. By providing the reference voltage to a sample-and-hold circuit and using an output of the sample-and-hold circuit to feed a comparator, synchronization may be accomplished. Each internal clock signal is generated by different reference capacitor and current source circuit.

Abstract: A clock controlling circuit and method for eliminating the delay difference in the entire clock propagation line. Circuit scale is reduced as compared to a case of using a PLL or DLL circuit. A timing averaging circuit 10 is fed with clocks from a position on a forward route 111 of a direction-reversed clock propagation path, adapted for being fed with input clocks at its one end, and from a position on a return route 112 corresponding to the position on the forward route 111. The timing difference between these clocks is averaged to output an averaged timing difference.

Abstract: A differential sinusoidal signal pair is generated on an integrated circuit (IC). The differential sinusoidal signal pair is distributed to clock receiver circuits, which may be differential amplifiers. The clock receiver circuits receive the differential sinusoidal signal pair and convert the differential sinusoidal pair to local clock signals. Power consumption and noise generation are reduced as compared to conventional clock signal distribution arrangements.

Abstract: A parallel data interface and method is provided herein, which adjusts a timing relationship of a clock signal to not only minimize clock skew, but to also compensate for noise components that may affect one or more paths of a parallel data bus. In some embodiments, the parallel data interface includes a first phase generator coupled to generate a first plurality of time delay pulses, and a first phase selector adapted to select one of the first plurality of time delay pulses to adjust the timing of a clock signal to sample each and every one of the plurality of data signals between minimum setup and hold time thresholds. In some embodiments, the parallel data interface includes a second phase generator coupled to generate a second plurality of time delay pulses, and a second phase selector adapted to select one of the second plurality of time delay pulses to adjust the timing of the clock signal to output the plurality of data signals from the data interface at least an amount of time (i.e.

Abstract: A complementary signal generator, for outputting complementary positive-phase and antiphase signals that vary between a first logical value and a second logical value, which includes a signal forming unit for outputting a positive-phase intermediate signal being in phase with an input signal varying between the first logical value and the second logical value, and an antiphase intermediate signal antiphase to the input signal. The generator also includes a first connecting means for simultaneously transferring the second logical value of the positive-phase intermediate signal and the first logical value of the antiphase intermediate signal to a positive-phase signal output part and an antiphase signal output part in synchronism with a state change of the input signal from the first logical value to the second logical value.

Abstract: An oscillator that can be used within a high voltage generation and regulation system for non-volatile memory. The system may comprise a charge pump that may have at least one pump and an oscillator. In one aspect the oscillator provides clock signals to the pump. The output of the oscillator may be disabled without turning off the clock generation. The oscillator may be a ring oscillator. In one aspect, the ring oscillator and the output stage may comprise inverters with a capacitor coupled to the output of the inverter. In one aspect, the ratio of the capacitors in the ring oscillator to the capacitor in the output stage determine the phase shift between the two clock signals. In another aspect, the capacitance of the capacitors are identical and a bias applied the ring oscillator and the output stage are radioed to adjust the phase between the two clock signals.

Abstract: The present invention provides a method to balance a clock tree dynamically. A controllable buffer is inserted in a specific level of a clock tree, and a controller is provided for adjusting two clocks with different skew by controlling the PMOS/NMOS arrangements in the controllable buffer so as to generate more current for compensating the time delay of slow clock to a sink. This method effectively suppressed the clock skew generated by the voltage drop or the temperature variations in the synchronous logic circuit design.

Abstract: A clock controlling circuit and method for eliminating the delay difference in the entire clock propagation line. Circuit scale is reduced as compared to a case of using a PLL or DLL circuit. A timing averaging circuit 10 is fed with clocks from a position on a forward route 111 of a direction-reversed clock propagation path, adapted for being fed with input clocks at its one end, and from a position on a return route 112 corresponding to the position on the forward route 111. The timing difference between these clocks is averaged to output an averaged timing difference.

Abstract: A multi-phase clock signal generator provides multiple clock signals from an input clock signal, the multiple clock signals being inverted from one another and having substantially the same delay and duty cycle characteristics. Methods of generating multiple clock signals are also provided.

Abstract: Multiphase clock generators and methods are provided. A multiphase clock generator has a first clock divider for generating a first-phase clock signal from a first input clock signal. A first logic gate is connected to an output port of the first clock divider. A second clock divider is connected to an output port of the first logic gate. The second clock divider is for generating a second-phase clock signal from the first input clock signal. A second logic gate is connected to an output port of the second clock divider. A third clock divider is connected to an output port of the second logic gate. The third clock divider is for generating a third-phase clock signal from a second input clock signal.

Abstract: A signal deskew circuit is provided, which includes first and second signal branches, each branch extending between a start location and a respective end location. Each signal branch includes a send path and a return path, which have substantially the same propagation delays. An adjustable delay buffer is coupled in the send and return paths of a first of the signal branches and has a delay, which is adjustable based on a respective adjust signal. A skew sensor coupled to the return paths of the first and second signal branches, which generates the respective adjust signal for the adjustable delay buffer based on a phase difference between signals on the return paths of the first and second signal branches.

Abstract: Transistor bodies are biased to modify delay in clock buffers.

Abstract: So as to generate multiple output signals whose phases are evenly spaced about 360 degrees, and having a frequency equal to that of an input signal, a phase multiplier circuit includes three or more instances of a phase multiplier subcircuit and additional circuitry configured in a negative feedback loop. Each phase multiplier subcircuit includes a difference circuit, a loop filter transistor, and a voltage-controlled delay circuit. The difference circuit converts to a phase current a delay from an input signal to the delay circuit to an output signal from the delay circuit, and subtracts from the phase current a bias current proportional to the smallest positive delay from the output signal with the largest phase to the output signal with the smallest phase. The subtracted current is integrated by the loop filter transistor, and steady-state operation is achieved when for each phase multiplier subcircuit, the bias current is equal to the phase current.

Abstract: In an integrated circuit device, a clock signal distribution section is arranged in an outer circumferential area of a semiconductor chip to supply a clock signal. Each of interface circuit blocks has at least an internal circuit operating based on the clock signal supplied from the clock signal distribution section.

Abstract: A clock controlling circuit and method for eliminating the delay difference in the entire clock propagation line. Circuit scale is reduced as compared to a case of using a PLL or DLL circuit. A timing averaging circuit 10 is fed with clocks from a position on a forward route 111 of a direction-reversed clock propagation path, adapted for being fed with input clocks at its one end, and from a position on a return route 112 corresponding to the position on the forward route 111. The timing difference between these clocks is averaged to output an averaged timing difference.

Abstract: Clock signal generators include an integrated circuit chip having a PLL-based or DLL-based clock driver therein. The clock driver is configured to support generation of a plurality of clock signals having different frequencies in a range between 1 and 1/N times a frequency of an internal clock signal and full-period programmable skew characteristic, where N is a positive integer greater than one. The clock driver also includes a divide-by-N clock generator that is configured to generate N divide-by-N clock signals that have the same frequency but are phase shifted relative to each other. This clock generator operates in response to a first skew signal having a frequency equal to the frequency of the internal clock signal. A one-of-N select circuit is provided. This select circuit is configured to select one of the N divide-by-N clock signals in response to a time unit position signal.

Abstract: An exemplary reduced-power-consumption network includes a frequency divider coupled through global clock lines to a plurality of double-edge triggered registers. Another exemplary network includes a plurality of individually programmable frequency dividers coupled through local clock lines to a plurality of double-edge triggered registers.

Abstract: A second clock is generated as an intermittent train of pulses by removing some pulses from a first clock having a predetermined period, and is supplied as an internal clock to internal circuits of a semiconductor integrated circuit device. At the same time, a current generating circuit for consuming a power supply current is operated in timed relation to a third clock which comprises a train of pulses to be removed from the first clock.

Abstract: A modular Digital Locked Loop (DLL) architecture capable of generating a plurality of multiple phase clock signals, having particular applicability to synchronization of embedded DRAM systems with on chip timing. The architecture comprises a single core frequency locking circuit that includes a delay element with control logic and locking circuitry capable of locking the DLL system clock frequency to an external reference clock, and a plurality of secondary phase locking circuits capable of synchronizing a plurality of internal clock signals to any phase of the external reference clock.

Abstract: A self-alignment system for complement clock signals includes a first delay circuit and a second delay circuit. A first clock signal may be propagated through the first delay circuit and a second clock signal may be propagated through the second delay circuit. A propagation delay of each of the first and second delay circuits may be selectively varied as a function of the first and second clock signals.

Abstract: A clock distribution network for clock distribution in an integrated circuit (IC) using digital feedback for skew compensation and jitter filtering. In an embodiment, a number of clock processor nodes are distributed throughout the clock distribution network on the IC at respective local clock regions. A master clock generator generates a master clock for distribution to the clock processor nodes, via the clock distribution network, to compensate clock skew and filter clock jitter locally at the respective local clock regions.

Abstract: A state machine, a counter, and related method for gating redundant triggering clocks according to the initial states is provided. The state machine includes a plurality of state units and a clock gating circuit. Each of the state unit is triggered by a clock to generate a corresponding varying state, and the clock gating circuit is capable of selectively withholding a triggering clock to at least one state unit according only to an initial state, such that the selected state unit(s) will not be triggered by the triggering clock while the rest of the state units are triggered by the triggering clock to update their corresponding states.

Abstract: A local clock signal generation system is disclosed including multiple local clock buffers each receiving a global clock signal and producing a version of one or more local clock signals derived from the global clock signal. Each local clock buffer includes an input section and an output section. The input sections are substantially identical such that timing differences between the versions of the one or more local clock signals are reduced. An electronic circuit is described including the local clock signal generation system and a latch (e.g., a master latch of a flip-flop). A local clock buffer produces a gating signal and a local clock signal received by the latch. When the gating signal is a certain logic value, the local clock signal is a steady logic value, and the latch produces an input data signal as an output signal. An integrated circuit including the electronic circuit is disclosed.

Abstract: According to some embodiments, a plurality of ring oscillators are associated with a generation and/or distribution of a clock signal.

Abstract: A master DLL circuit (3) generates a first delay signal (CKD) by delaying the master clock signal by a first delay time (T0) and generates a first pulse signal (Smp) having a pulse width (T0) of the first delay time, and generates a first control signal (Scp) which is changed in accordance with the first pulse signal (Smp), and adjusts the first delay time (T0) in accordance with the first control signal (Scp). Each slave DLL circuit (D1 to Dm) delays, by a second delay time (td), a delay internal clock signal, and outputs the delayed delay internal clock signals (CK1 to CKm) which form the multiphase clock signals. Each slave DLL circuit generates a second pulse signal (Ssp) having a pulse width (td) of the second delay time, and generates a second control signal (Scp1) which is changed in accordance with the first and second pulse signals (Smp, Ssp), and adjusts the second delay time (td) in accordance with the second control signal (Scp1), thus reducing a skew value of the multiphase clock signal.

Abstract: A low loss on-die interconnect structure includes first and second differential signal lines on one of the metal layers of a microelectronic die. One or more traces may also be provided on another metal layer of the die that are non-parallel (e.g., orthogonal) to the differential signal lines. Because the traces are non-parallel, they provide a relatively high impedance return path for signals on the differential signal lines. Thus, a signal return path through the opposite differential line predominates for the signals on the differential lines. In one application, the low loss interconnect structure is used within an on-die salphasic clock distribution network.

Abstract: A clock controlling circuit and method for eliminating the delay difference in the entire clock propagation line. Circuit scale is reduced as compared to a case of using a PLL or DLL circuit. A timing averaging circuit 10 is fed with clocks from a position on a forward route 111 of a direction-reversed clock propagation path, adapted for being fed with input clocks at its one end, and from a position on a return route 112 corresponding to the position on the forward route 111. The timing difference between these clocks is averaged to output an averaged timing difference.

Abstract: In integrated circuit (IC) devices, skew concerns between the clock pulses supplied to different latches hinder high speed operation. An IC device therefor includes a first clock processor means to generate a third clock pulse in response to first and second clock pulses with identical phase and frequency, a second clock processor means to generate a fifth clock pulse in response the third clock pulse and a fourth clock pulse with identical phase and frequency, and first and second latch groups each including a plurality of latches, in which the second clock pulse is generated via a buffer or divider from the third clock pulse, a fourth clock pulse is generated via a buffer or divider from the fifth clock pulse, and the third and fifth clock pulses are supplied to the first and second latch groups via a buffer, respectively.

Abstract: Phased clock generator circuits and methods that use counters to define the desired positions of the phased output clock edges. A plurality of counters are each clocked by a count clock relatively much faster than the input clock. A first counter counts for one input clock period, and the counted value is stored. The stored value is then divided and added to provide the number of counts in various fractions of the input clock period. The divided and/or added values are provided to a second counter that counts from zero and generates various pulses at desired times throughout the input clock period. The pulses from the second counter are used (sometimes in combination with the input clock signal) to provide phased output clock signals at predetermined times during the input clock cycle. Some embodiments include a duty cycle correction feature. In some embodiments, duty cycle correction is optional.

Abstract: Described are methods and systems for distributing low-skew, predictably timed clock signals. A clock distribution network includes a plurality of dynamically adjustable clock buffers. A control circuit connected to each clock buffer controls the delays through the clock buffers in response to process, voltage, and temperature variations, and consequently maintains a relatively constant signal-propagation delay through the network. In one embodiment, each clock buffer includes skew-offset circuitry that adds to or subtracts from the PVT compensated delay values provided by the PVT control circuit to simplify clock skew minimization.

Abstract: Multiphase clock generators and methods are provided. A multiphase clock generator has a first clock divider for generating a first-phase clock signal from a first input clock signal. A first logic gate is connected to an output port of the first clock divider. A second clock divider is connected to an output port of the first logic gate. The second clock divider is for generating a second-phase clock signal from the first input clock signal. A second logic gate is connected to an output port of the second clock divider. A third clock divider is connected to an output port of the second logic gate. The third clock divider is for generating a third-phase clock signal from a second input clock signal.

Abstract: A method and related circuitry for driving output signals of a chip is disclosed. The method includes driving output signals with an even number of inverter driving circuits, and keeping an equivalent load of each inverter of the driving circuits substantially identical by keeping impedances of each driving circuit substantially identical.

Abstract: Disclosed is an apparatus for generating two constant width and symmetrical drive signals from two separate, but complementary, pulse width modulated control signals while also generating two pulse width modulated drive signals corresponding to said pulse width modulated control signals. The constant width drive signals are generated through the use of a toggle or latch set/reset circuit actuated by a given characteristic of each of the control signals.

Abstract: A digital frequency synthesizer (DFS) circuit adds little additional delay on the clock path. True and complement versions of an input clock signal are provided to a first and second passgates, respectively. Under the direction of a control circuit, the passgates pass selected rising edges of the true clock signal, and selected falling edges of the complement clock signal, to an output clock terminal of the DFS circuit. When neither the true nor the complement clock signal is passed, a keeper circuit retains the value already present at the output clock terminal. In some embodiments, both passgates can be disabled and a ground or power high signal can be applied to the output terminal. Other embodiments include PLDs in which the DFS circuits are employed to allow individual clock control for each programmable logic block.

Abstract: A semiconductor integrated circuit device for minimizing clock skew over clock wiring shortened for reduced wiring delays. A plurality of stages of clock drivers are provided on clock wiring paths ranging from a clock generator to flip-flops. Clock lines connecting upper stage clock drivers are equalized in length in the form of a tree structure, and clock lines connecting lower stage clock drivers are made as short as possible.

Abstract: A semiconductor integrated circuit is disclosed, which comprises a tree structure of buffer circuit groups configured to have an enable-signal-controlled AND buffer circuit at least in a final stage, a latch circuit provided in a correspondence to the enable-signal-controlled AND buffer circuit and configured to receive an enable signal and clock signal and deliver an output to an input portion of a final stage buffer circuit, an enable-signal-controlled AND buffer circuit provided in a portion of an intermediate stage of the buffer circuit groups, and an OR circuit provided in a correspondence to the intermediate stage enable-signal-controlled AND buffer circuit and configured to take a logical sum of a plurality of enable signals for controlling the operations of a plurality of enable-signal-controlled AND buffer circuits more on a load circuit side and deliver a logical sum output to an input portion of the intermediate stage enable-signal-controlled AND buffer circuit.

Abstract: A circuit and method for synchronized clocking of components such as registers. Registers are clocked by individual component clock signals having the same frequency but potentially different phases due to differing propagation delays. Separate component clock signals are received by registers are brought into phase by evaluating the phases of the component clock signals at the registers, and synchronizing the component clock signal of each register to that of the previous register in a sequence.

Abstract: An input buffer includes first and second cross-coupled differential amplifiers. Each amplifier drives a buffer signal from a first logic state to a second logic state at a first slew rate when input signal transitions from a first logic state to a second logic state and a complementary input signal transitions from the second logic state to the first logic state, and drives the buffer signal from the second logic state to the first logic state at a second slew rate when the signal transitions are the complement of these previous transitions. An output circuit generates a first edge of an output signal when the buffer signal from the first amplifier transitions from the first logic state to the second logic state and generates a second edged of the output signal when the buffer signal from the second amplifier transitions from the first to the second logic state.

Abstract: A power saving hierarchical clock gating circuit includes a first level clock gate, a plurality of second level clock gates connected to the first level clock gate, and a plurality of third level clock gates for selectively providing a clock signal to a functional block. Each third level clock gate is connected between a second level clock gate and a register, or other low level device, of the functional block for selectively providing the clock signal to the register. Accordingly, the clock signal is conveyed from the first level clock gate through a second level and a third level clock gate to a register when the corresponding first, second, and third level clock gates are activated by associated decision logic.

Abstract: A computer of the present invention contains: a CPU; plural peripheral devices controlled by the CPU; a data transmission bus between the CPU and the peripheral devices and between the peripheral devices; and a clock signal source for supplying clock signals for CPU operation and data transmission. The clock signal source contains a PLL synthesizer, and two clock signals (one for the CPU and the other for the bus) are outputted from the PLL synthesizer to stop unnecessary signals (other than the clock signals) from being produced.