Abstract: A frequency forming circuit according to the present invention utilizes division by a partial fraction a/b, and therein pulse removal means (2) first remove a-b pulses from the end of each consecutive period equal in length to a pulses. Thereafter, the pulse string is conducted to a digital delay line (4) consisting of serially connected, controllable elements (5) that produce essentially the same unit delay, and which includes an intermediate output before each element. Each pulse in said period is output from the delay line (4) before the element (5) whose ordinal number in the delay line is the same as the ordinal number of the pulse in said period. A multiplexer (7) receives the pulses from the intermediate outputs of the digital delay line and combines them to form a new pulse string. Control means (6) cause the control elements (5) of the digital delay line (4) to produce an average unit delay (a-b)*t/b with the same control.

Abstract: A pulse signal shaper supplying a pulse signal having a stable pulse width, including an input circuit that produces a first pulse signal in response to an input signal, a delay circuit that produces a second pulse signal obtained by delaying the first pulse signal by a predetermined time, and a signal mixing circuit that is connected to the input circuit and the delay circuit. The mixing circuit combines the first pulse signal and the second pulse signal to produce a third pulse signal having a pulse width equal to or greater than a delay time provided by the delay circuit, and supplies the third pulse signal as an output signal from the pulse signal shaper. In a preferred embodiment, the input circuit includes an oscillator responsive to the input signal. When the input signal has a higher frequency than a predetermined frequency, the input signal is supplied as the first pulse signal at a frequency equal to te frequency of the input signal.

Abstract: The present invention provides a circuit (10) and method for providing a delayed output signal which is less sensitive to supply variation compared to conventional circuits, has high noise immunity, can be operated at high frequency, and occupies a minimum area on the semiconductor. The delay is provided according to the present invention by separately controlling the discharge currents of a capacitor (26) before and after the trip point voltage of an output inverter (16) of the circuit (10) has been reached. The delay interval is determined primarily by the capacitor value, the voltage difference between the supply and the trip point of the output inverter, and the first discharge current, set by a resistor (24) in series with a transistor (34). The second discharge current is set by a switch (36) having a series of transistors (38, 40).

Abstract: A delay line circuit is provided that precisely delays the incoming referenced clock signal by utilizing two delay cells and a sample-and-hold circuit. The circuit eliminates the need for sensing circuitry at the output to determine if the need to monitor the delay line circuit is operating in an undesirable operation. By eliminating the sensing circuitry the reliability of delay line circuit is significantly increased.

Abstract: A clock applying circuit for a synchronous memory is comprised of a clock input for receiving a clock input signal, apparatus connected to the synchronous memory for receiving a driving clock signal, and a tapped delay line for receiving the clock input signal and for delivering the clock driving signal to the synchronous memory in synchronism with but delayed from the clock input signal, the delay being a small fraction of the clock period of the clock input signal.

Abstract: The present invention concerns a delay circuit that provides a fixed amount of delay that is generally independent of process variations. An input resistance is provided that may be presented to a threshold device, such as an inverter, that may then be presented as an output. The output of the threshold device may also be presented through a feedback path comprising a capacitive device to the input of the threshold device. The feedback through the capacitive load actively resists the movement of the load. As a result, the delay provided by the circuit is generally resistant to process variations.

Abstract: A digital delay circuit structure includes a digital calibration circuit and a digital delayed signal generator. The digital delay circuit is automatically calibrated when a calibrate signal goes active. Once the auto-calibration process is completed, the circuit switches back to a normal delay mode operation where the digital delay circuit remains until the next transition of the calibrate signal. A calibration control circuit generates a sample gate signal which initiates a feedback signal to the input terminal delay chain circuit that causes the delay chain output signal to oscillate. A calibration counter circuit counts the oscillations and couples this information to a count decoder circuit which in turn generates a signal to select one of a plurality of taps in the delay chain circuit. The digital delay circuit automatically compensates for delay variations caused by process extremes, temperature, and average voltage changes.

Abstract: An object of the invention is to provide a variable delay circuit having a desired optional resolution.A variable delay section 24 is provided with paths A and B which carry signals input to an input terminal 21 to an output terminal 22, and a selection section for switching the paths A and B in accordance with a select signal. Ring oscillators 25 and 29 have oscillation periods which are x times and y times the delay time of the respective paths A and B. Phase comparison circuits 27 and 31 respectively compare, the phase of a first clock signal and the output from the ring oscillator 25, and the phase of a second clock signal and the output from the ring oscillator 29. Delay time control circuits 28 and 32 then respectively control the oscillation periods of the ring oscillators 25 and 29 so as to be equal to the respective periods of the first clock signal and the second clock signal, based on the phase comparison results, and control the delay times of the paths A and B.

Abstract: Internal node timing on an integrated circuit which is supplied with a clock signal from a system clock, the cycle time of which can be varied is measured by connecting a sequential element such as a latch to the node to measured and clocking it with a delayed measurement clock while increasing the clock cycle time. The output of the sequential element is an output pin of said integrated circuit. The measurement clock has the same cycle time as the system clock but has a latching edge delayed, the delay being at least 1.5 times the nominal system clock cycle time when it is desired to make measurement over both the high phase and low phase. The output pin is observed and the clock cycle time at which the sequential element fails to latch the current value determined. In a further embodiment, two sequential elements are used to make two measurements of this type and the difference between the two measurements is used to compute the time delay between the two nodes being measured. One node may be a clock node.

Abstract: A circuit for driving a capacitive load uses a plurality of driving signals with different phases including a quiescent time, and a driving time having a driving duration and an other time. An inductance element is connected across the driving terminals of the capacitive load, and a switch circuit is provided between a driving voltage source and the capacitive load. During the quiescent time, the switch circuit is closed to make the driving voltages the same potential, minimizing energy loss since no current flows during the quiescent time. During the driving time, the switch circuit is closed for a predetermined driving duration to clamp a sine wave around the peaks of the waveform, and the switch circuit is open during the other time when the sine wave is not at any of its peaks.

Abstract: A controllable precision delay line implemented in a digital integrated circuit device including a counter circuit for measuring a representative propagation delay for a delay element in the digital integrated circuit, and a binary controlled digital delay line responsive to the counter circuit and including L delay stages respectively having 2.sup.0 through 2.sup.L-1 delay elements, wherein the delay stages are controllably switched into a delay path pursuant to the measured representative propagation delay. Preload connections are provided between the outputs of delay elements of stages S(0) through S(L-2) and inputs of delay elements of the next in sequence stages S(1) through S(L-1) to prevent glitches being imposed on the delayed signal during adjustments in the number of stages included in the delay path.

Abstract: A timing vernier produces a set of timing signals of similar frequency and evenly distributed in phase by passing an input reference clock signal through a succession of delay stages, each stage providing a similar signal delay. A separate one of the timing signals is produced at the output of each delay stage. The reference clock signal and timing signal output of the last delay stage are supplied as inputs to a phase lock controller through separate adjustable first and second delay circuits. The phase lock controller controls the delay of all stages so that the timing signal output of the last stage is phase locked to the reference clock. In accordance with the invention, the delays of the first and second delay circuits are adjusted to compensate for controller phase lock error.

Abstract: This is an integrated timing circuit which can be formed on a microprocessor chip. The circuit uses an oscillator having a delay line and a variable delay element. The delay line and the delay element vary together to hold the velocity of signal propagation in the circuit substantially constant. The output, of the oscillator is coupled to one input of a comparator circuit. A series of inverter circuits, each of which has a respective variable delay are connected to the input of the oscillator and to a second input of the comparator circuit such that the comparator circuit senses the difference between the output signal of the inverter series and the output signal of the oscillator circuit to provide an error signal proportional to the sensed difference. A feedback loop is provided, to the variable delay means in said oscillator and to the inverter circuits to correct for the sensed difference, to establish a uniform and stable time standard at the output of the oscillator.

Abstract: A programmable digital delay unit presenting a number of cascade-connected delay blocks, and a number of controlled bypass elements, one for each delay block. Each bypass element presents a bypass line and a multiplexer for selectively connecting the input or output of the respective delay block to the input of the next delay block. The delay blocks are formed by the cascade connection of flip-flops, and the number of flip-flops in each successive delay block, from the input of the delay unit, decreases in an arithmetic progression to the power of two, so that the selection signals for the respective multiplexers represent the bits of a digital word specifying the required delay.

Abstract: A binary relative delay line device having two delay lines, each of which delays, during a time interval, an input signal by a substantially equal amount of time. Each delay line requires a settling time before it is selected during a next time interval. A selection and delay determining circuit is coupled to the two delay lines to select one of them to provide an output signal. A clock is coupled to the selection and delay determining circuit to operate the selection and delay determining circuit at a lower frequency than the frequency of the input signal, the lower frequency being chosen so that any selected delay line has settled before it is selected.

Abstract: A delay circuit having at least two memory cells (3, 4, 5, 6, 8, 9) each including a capacitive memory element (20, 26, 40, 45), a write transistor (22, 28, 42, 47) by which information to be delayed can be written from a write line (18) into the capacitive memory element (20, 26, 40, 45), and a read transistor (21, 27, 41, 46) by which information can be read from the capacitive memory element (20, 26, 40, 45) on a read line (19), and having a control arrangement which is clocked by means of a first control clock and whose input receives a control signal and which includes intercoupled control circuits (11, 12, 13, 14, 15, 16) one of which is associated with a respective memory cell (3, 4, 5, 6, 8, 9), each control circuit (11, 12, 13, 14, 15, 16) of the read transistor (21, 27, 41, 46) of the associated memory cell (3, 4, 5, 6, 8, 9) being controllable by means of the input signal and each control circuit (11, 12, 13, 14, 15, 16) of the write transistor (22, 28, 42, 47) of the associated memory cell being c

Abstract: A pulse shaping filter for shaping pulses received at a specified data rate is disclosed. The filter has a desired impulse response associated with a plurality of sampled values. The filter includes a sampling circuit responsive to the input pulses, such that each pulse is sampled at a desired sampling rate. A delay circuit provides a plurality of delayed versions of the sampled pulse, wherein said sampled pulse propogate through said delay circuit at a unit delay time substantially equal to the period of the desired sampling rate. A plurality of resistors are coupled to the delay circuit, each resistor providing a weighing coefficient by which the delayed versions of the sampled pulses are multiplied to provide a plurality of weighed delayed pulses. A summing circuit is adapted to add all said weighed delayed pulses to provide shaped pulses.

Abstract: A circuit for holding constant the propagation delay time at an output terminal in response to an input signal having a varying transition time from one logic state to another logic state at an input terminal is provided. The circuit has a plurality of inverters, each inverter having an input node and an output node, connected in series between the input terminal and the output terminal. The circuit also has a first capacitive means coupled to one of the first inverter output nodes through a switch, and has a means coupled between the input terminal and the switch for engaging the switch to couple the capacitive means to one of the first inverter output nodes. The engaging means is timed to couple the capacitive means responsive to the transition time of the input signal whereby the propagation delay time at the output terminal is constant.

Abstract: A plurality of binary signals each having first and second logic levels respectively representing a binary "1" and a binary "0" and each indicating a binary digit of an individual binary significance cumulatively represent an adjustable delay to be provided by a plurality of delay elements. A first particular number of the binary signals of greatest binary significance are decoded to provide, in a thermometer code, a plurality of signals each having first and second amplitudes. The signals in the thermometer code control the operation of individual switches each having first and second operative relationships to provide respectively for a maximum delay or a minimum delay in an associated one of the delay elements. The binary signals of least binary significance are decoded to produce an analog signal variable between the first and second amplitudes.

Abstract: The delay line separator extracts a clock signal from a combined data/clock encoded signal received over a serial data bus, despite the presence of significant duty cycle distortion. Such distortion affects the width of symbols within received data packets but does not affect the timing between successive rising edges within the received pulse string. To extract the chock signal from the distorted signal, the separator exploits a pre-filter circuit which generates 2 -nanosecond pulses synchronized with each rising edge in the received signal. A 20-nanosecond pulse train is transmitted down a delay line having twelve delay elements. Circuits are connected to every other delay element within the delay line for generating 10-nanosecond pulses, synchronized with each rising edge of the pulse train. Outputs from the circuits are combined using an OR gate to yield a 10-nanosecond clock signal.

Abstract: A plurality of binary signals each having first and second logic levels respectively representing a binary "1" and a binary "0" and each indicating a binary digit of an individual binary significance cumulatively represent an adjustable delay to be provided by a plurality of delay elements. A first particular number of the binary signals of greatest binary significance are decoded to provide, in a thermometer code, a plurality of signals each having first and second amplitudes. The signals in the thermometer code control the operation of individual switches each having first and second operative relationships to provide respectively for a maximum delay or a minimum delay in an associated one of the delay elements. The binary signals of least binary significance are decoded to produce an analog signal variable between the first and second amplitudes.

Abstract: A process tolerant delay circuit includes a plurality of inverters that receive an input signal and provide an output signal related to the input signal but including a propagation delay of the plurality of inverters. At least one inverter comprises FETs of minimum channel lengths dependent upon a fabrication process by which the circuit was made. Accordingly, the plurality of inverters have a propagation delay dependent upon the fabrication process. A delay compensation device receives the output signal of the inverters and provides a compensated output signal related to the received signal but including a variable delay established in accordance with a control signal. A process sense stack provides the control signal only during a transition of the input signal, and with a value dependent upon a channel length of a FET device thereof.

Abstract: A delay line circuit is provided that precisely delays the incoming referenced clock signal by utilizing two delay cells and a sample-and-hold circuit. The circuit eliminates the need for sensing circuitry at the output to determine if the need to monitor the delay line circuit is operating in an undesirable operation. By eliminating the sensing circuitry the reliability of delay line circuit is significantly increased.

Abstract: A clocking circuit and clocking method provide a clocking signal that tracks supply voltage VDD such that as supply voltage VDD increases, the signal generation delay also increases. Complementary circuit embodiments and methods are described. In one clocking circuit, a capacitive load stores an amount of charge that varies with supply voltage VDD. A discharge circuit linearly discharges the capacitive load under control of a switch which is responsive to an input signal. A detection circuit is coupled to the capacitive load for detecting linear discharging of the capacitive load to a trigger level V.sub.0 and for providing the clocking signal upon detection of the trigger level. The trigger level is predefined and substantially independent of variation in supply voltage VDD. The clocking techniques presented can be advantageously employed within memory devices such as DRAMs or SRAMs.

Abstract: A frequency multiplier circuit comprising a first delay circuit for delaying sequentially a reference clock signal, a frequency doubler for delaying the reference clock signal and combining logically the delayed reference clock signal and the reference clock signal, a second delay circuit for delaying sequentially an output signal from the frequency doubler, a signal detector for logically combining the output signal from the frequency doubler and a plurality of output signals from the second delay circuit to detect a desired duty factor of signal, a decoder for decoding a plurality of output signals from the first delay circuit and a plurality of output signals from the signal detector to output a signal delayed by n times half a period of the reference clock signal, and a frequency generator for logically combining an output signal from the decoder and the reference clock signal to generate a multiple frequency of that of the reference clock signal.

Abstract: A charge transfer device having an improved signal stage is disclosed. This stage includes a floating region formed in a semiconductor layer and receiving signal charges from a charge transfer stage, a reset drain region formed in the semiconductor layer adjacently to the floating region, a reset gate for resetting the floating drain region in potential to the reset drain region, an absorption region formed in the semiconductor layer adjacently to the reset drain region, a barrier gate supplied with a constant voltage to form a channel region between reset drain region and the adsorption region, and a charge injection source connected to the reset drain region to inject charges thereinto.

Abstract: A clock is phase shifted by an amount controlled by the value of a control signal by establishing at least several discrete delay times to be imposed on the clock. The control signal value controls selection of the imposed discrete delay time. An analog-to-digital converter of a phase locked loop responds to intelligence representing variable phase bits and the selected phase shifted clock to control the signal value. The selected replica is derived by at least several cascaded substantially equal time delay units. In one embodiment, a multiplexer responds to the clock, and the signal value, which is Gray coded, to control connections from one of the delay units to an output terminal. In another embodiment, the number of cascaded delay units interposed between the clock and an output terminal is controlled by the signal value.

Abstract: A method and apparatus for multi-range delay control is disclosed. A method furnishes an output signal (S.sub.K) with a delay that is variable with respect to an input signal (e.sub.0). To enable precise adjustment as a function of a set-point delay (CN) over a plurality of scales, a succession of signals (e.sub.1, e.sub.2, . . . , e.sub.n) delayed with respect to the input signal (e.sub.0) are produced, the delay between a delayed signal (e.sub.2) and the preceding signal (e.sub.1) having a predetermined value. One of the delayed signals (e.sub.2) and a preceding signal (e.sub.1) as selected and a superposition is performed with weighting and an integral effect of the selected signals (e.sub.1, e.sub.2), the selection and weighting being determined as a function of the set-point delay (CN).

Abstract: A multiple-phase clock signal generator includes a phase-locked loop (PLL) for generating an oscillating signal having a predetermined frequency, a counter driven by the oscillating signal and having a plurality of outputs, and a plurality of combinational logic gates each having a plurality of inputs and an output. Selected ones of the inputs of each combinational logic gate are coupled to selected outputs of the counter to produce, at the output of each combinational logic gate, a clock signal having a particular phase. Different combinations of the outputs of the counter can be used to generate different phases.

Abstract: A programmable delay line comprises a plurality of delay stages connected in series, each of the delay stages including: a basic path for passing an input signal; a delay path for passing the input signal with a predetermined delay time; and a selector for selecting either the basic path or the delay path to pass the input signal in accordance with digital data externally inputted, wherein differences in times for passing the input signal through the basic path and through the delay path in the plurality delay stages are UD.2.sup.n (n=0, 1, 2 . . . ), UD being unit delay time. A programmable delay apparatus comprises: an oscillator and counter, which determine a coarse delay time in accordance with the upper bit data of control data, and a programmable delay line, which determines a fine delay time according to the lower bit data of the control data after the finish of the coarse delay time to obtain a total delay time. The counter provides a wide range of available delay times.

Abstract: A variable drive strength buffer circuit is provided that automatically adjusts its associated drive strength to compensate for variations in manufacturing parameters, environmental conditions and operating conditions. As a result, electromagnetic interference, power supply noise, edge rates and ringing may be reduced. The self-adjusting variable drive buffer circuit may be fabricated on an integrated circuit and includes a speed detector unit that measures the relative speed of the integrated circuit. In one embodiment, a self-adjusting variable drive strength buffer circuit includes a circuit speed detector unit having a delay chain consisting of a plurality of variable delay elements. When the delay chain length is matched to the period of an input clock, the length of the chain is an accurate measure of the relative "speed" of the transistors making up the delay chain and therefore of the other transistors on the integrated circuit chip.

Abstract: Disclosed is a digital phase-locked loop circuit which provides a control signal (332, 334) for a delay circuit (304, 306, 308, 310) within the feedback path of the phase-locked loop. The circuit has a first series of delay circuits (304, 306, 308, 310), which have an incremental control signal input (332, 334), to delay an input clock signal (302) to provide the D input (311) to a D flip flop (312). The input clock signal (302) is also connected to a second series of delay circuits (314, 316, 318, 320, 322). The output of this second series (314, 316, 318, 320, 322) is connected to the clock input (323) of the D flip flop (312). The voltage controlled delay signal input for the second series of delay circuits (314, 316, 318, 320, 322) is supplied by a reference control signal (124, 126). The output of the D flip flop (312) is passed through a resistor-capacitor filtering circuit (324, 325) and fed back to the first series of delay circuits (304, 306, 308, 310) as the incremental control signal.

Abstract: The delay line separator extracts a clock signal from a combined data/clock encoded signal received over a serial data bus, despite the presence of significant duty cycle distortion. Such distortion affects the width of symbols within received data packets but does not affect the timing between successive rising edges within the received pulse string. To extract the clock signal from the distorted signal, the separator exploits a pre-filter circuit which generates 20-nanosecond pulses synchronized with each rising edge in the received signal. A 20-nanosecond pulse train is transmitted down a delay line having twelve delay elements. Circuits are connected to every other delay element within the delay line for generating 10-nanosecond pulses, synchronized with each rising edge of the pulse train. Outputs from the circuits are combined using an OR gate to yield a 10-nanosecond clock signal.

Abstract: A logic circuit is driven by a single alternating voltage power supply so that the energy stored in parasitic capacitances can be mostly recovered, rather than dissipated, as in conventional logic designs. Successive stages of the logic circuit are of opposite conductivity types such that the successive stages are activated in alternate half cycles of the power supply without separate clock signals. Each stage of the logic circuit is precharged during a respective first half cycle of the power supply and is active in logical processing during a second half cycle. The half cycles are defined by the rising and falling edges of the power supply. The logic circuit resonates with an inductor coupled across the power supply but closely coupled to the logic circuit. This inductor and the method of charging and discharging the capacitors in the logic circuit serve to minimize the power dissipated during logical processing.

Abstract: Use of inverse transforms regarding chirp-Z analysis is circumvented to ence the chirp-Z output gain. Forward chirp-Z transform pulses relating to individual CW frequency components of interest in a composite signal, are gated to circuitry which replicates those pulses to recreate each such component for the time necessary to accomplish the intended analysis. This circuitry operates at the replicating rate necessary to separate the pulse replications by one-half the width of the pulses.

Abstract: A time of arrival detector for an analog pulse signal digitizes the pulse, digitally delays the digitized signal in one path and converts the delayed signal back to a delayed analog version of the input signal. In a second path an undelayed analog version of the input signal is provided. A scaling offset is established to scale the delayed signal larger than the undelayed signal, and the delayed and undelayed signals are then compared to establish a time of arrival for the input pulse. A delta modulator is preferably used to provide the digitized signal, and also to provide the undelayed analog version of the input signal as the smoothed output of an integrator within the delta modulator. The undelayed modulator output is preferably attenuated by -3 dB, with the pulse's time of arrival obtained from the time at which the delayed analog signal rises above the undelayed but attenuated signal.