Abstract: In one embodiment, a circuit topology for use in an n-phase voltage controlled oscillator (VCO) or injection-locked frequency divider includes a transmission line ring having n transmission line delay segments connected at n junctions, where n is an integer greater than or equal to 3. Each transmission line segment provides a 1/n wavelength signal delay between adjacent junctions. The transmission line ring is coupled to a first power supply node. Each of the junctions has a respective transistor coupled thereto, each transistor having a first source/drain terminal coupled to its respective junction, a second source/drain terminal coupled to a second power supply node, and a gate terminal, wherein the gate terminal is coupled to a signal that is ½ wavelength out-of-phase with respect to a signal at the first source/drain terminal of the transistor.

Abstract: A random number generator comprises a first high frequency (HF) oscillator, a second low frequency (LF) oscillator, a delay buffer, a multiplexer, and a sampling circuit. The HF oscillator generates a high frequency oscillating signal. The LF oscillator generates a low frequency oscillating signal. The multiplexer selects from the LF oscillating signal and one or more delayed version of the LF oscillating signal to generate a third oscillating signal. The third oscillating signal is then used to sample the HF oscillating signal to output a random bit stream. In one preferred embodiment, the random bit stream is feedback to the multiplexer to make randomized selection. As a result, the original jitter distribution of the LF oscillating signal is increased to a larger jitter distribution of the third oscillating signal to increase the random behavior of the output bit stream.

Abstract: A random number generator comprises a first high frequency (HF) oscillator, a second low frequency (LF) oscillator, and a sampling circuit. The HF oscillator generates a high frequency oscillating signal. The LF oscillator generates a low frequency oscillating signal. The LF oscillating signal is used to sample the HF oscillating signal to generate a sequence of random bits. In one preferred embodiment, the LF oscillator comprises a plurality of stages of inverters, and each inverter comprises a number of series-stacked minimum length transistors. The LF oscillating signal has a jitter distribution due to thermal noise present in each transistor of the LF oscillator. By series stacking a number of minimum length transistors in each inverter, the overall thermal noise in the LF oscillator is maximized to increase the jitter distribution of the LF oscillating signal and thereby increase the random behavior of the sequence of random bits.

Abstract: An apparatus for generating a random bit sequence has a ring oscillator which includes inverting digital devices and on which an oscillator signal can be tapped. An intermediate storage element monitors and stores fluctuating levels of the oscillator signal. At least two controllable switch devices for simultaneously exciting at least two harmonic wave edges of the ring oscillator are provided in a signal path of the ring oscillator. The phasing of the two harmonic wave edges and a potential convergence thereof are subject to statistical fluctuations, which are used as a basis for the random bit generation. A corresponding random number generator can be used in particular as an FPGA for security applications, such as cryptographic methods. The apparatus has substantially digital components, which are easy to produce in a standardized manner. A dedicated regulating circuit is not necessary. The apparatus is also robust toward exterior influences.

Abstract: A frequency synthesizer includes a digitally-controlled oscillator and an oscillation frequency control unit. The digitally-controlled oscillator includes a loop-shaped transmission line path having an odd number of parallel portions in each of which two conductors are arranged in parallel to each other with a space therebetween, and an odd number of intersection portions in each of which two conductors intersect spatially, an active circuit coupled between the two conductors, and a first variable capacitance unit and a second variable capacitance unit. The oscillation frequency control unit includes a ?? modulation circuit for subjecting to ?? modulation a first control signal for switching a high capacitance state and a low capacitance state of a first variable capacitance element included in the first variable capacitance unit.

Abstract: A signal generating circuit and method are disclosed that do not require a phase-locked-loop and a low frequency temperature-stable oscillator. The method may include generating an oscillating output signal responsive to a feedback signal, where the feedback signal controls a frequency of the oscillating output signal, generating a current output signal having a magnitude corresponding to the frequency of the oscillating output signal, and then comparing the current output signal to a reference signal to generate the feedback signal. The signal generating circuit may include an oscillator circuit responsive to a feedback signal and a frequency-to-current conversion circuit configured to generate a frequency dependent current signal that is compared to a reference current to generate an output signal corresponding to the frequency of the oscillating output signal. A feedback conversion circuit compares the output signal with a reference signal to generate the feedback signal to the oscillator circuit.

Abstract: A disclosed current source circuit includes a current mirror circuit having two enhancement-type MOS transistors, a depletion-type MOS transistor configured to be connected to a drain of one of the two enhancement-type MOS transistors and to function as a constant current source, and a resistor configured to have a negative temperature property and be connected to a source of the one of the two enhancement-type MOS transistors.

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: A design structure for a programmable interpolative voltage controlled oscillator (VCO) with adjustable frequency range output is provided. Programmable delay cells whose size is modifiable based on control inputs to the programmable delay cells are utilized. A different set of control inputs may be provided to programmable delay cells of an inner sub-ring from the set of control inputs provided to programmable delay cells of a main ring of the VCO. The minimum frequency output of the VCO is governed by the main ring programmable delay cell strength with the maximum frequency output of the VCO being governed by a ratio of strengths of the main ring programmable delay cells to the inner sub-ring programmable delay cell. By modifying the control inputs to the inner sub-ring and main ring programmable delay cells, the minimum and maximum frequency outputs, and thus the range between these two frequency outputs, are made programmable.

Abstract: A differential resonant ring oscillator (“DRRO*) circuit using a ring oscillator topology to electronically tune the oscillator over multi-octave bandwidths. The oscillator tuning is substantially linear, because the oscillator frequency is related to the magnetic tuning of a YIG sphere, which has a resonant frequency equal to a fundamental constant multiplied by the DC magnetic field. The simple circuit topology uses half turn or multiple half turn loops magnetic coupling methods connecting a differential pair of amplifiers into a feedback loop configuration having a four port YIG tuned filter, thus creating a closed loop ring oscillator. The oscillator may use SiGe bipolar junction transistor technology and amplifiers employing heterojunction bipolar transistor technology SiGe is the preferred transitor material as it keeps the transistor's 1/f noise to an absolute minimum in order to achieve minimum RF phase noise.

Abstract: A voltage-controlled oscillator (VCO) circuit includes a level shifter, and a semiconductor device includes the VCO circuit. The VCO circuit includes an input voltage receiver, a current mirror, and a frequency oscillator. The input voltage receiver receives a first voltage input to the VCO circuit so as to generate a first current. The current mirror copies the first current so as to generate a second current. The frequency oscillator oscillates in response to the second current. The input voltage receiver includes a level shifter and a first current generator. The level shifter shifts a voltage level of the first voltage to a voltage level of a second voltage. The first current generator generates the first current corresponding to the second voltage.

Abstract: A random number generation system comprising one or more ring oscillators configured to generate entropy due to accumulated phase drift.

Abstract: An assistant measuring circuit for an oscillator is provided. The oscillator provides N oscillating signals with different phases. The assistant measuring circuit includes N buffers, N reflection-type modulators, and a controller. An ith buffer among the N buffers receives and further transmits an ith oscillating signal among the N oscillating signals. An ith modulator among the N modulators has an ith signal input end, an ith signal output end, and an ith signal control end. The ith oscillating signal is transmitted to the ith signal input end through the ith buffer. The signal output ends of the N modulators are all electrically connected to a measuring end. The controller is used for providing an ith control signal to the ith signal control end.

Abstract: An injection locking clock generator can vary the free running frequency of an injection locking oscillator to broaden an operating frequency range of an oscillation signal injected to itself, thereby performing an injection locking with respect to all frequencies of an operating frequency range. The clock generator includes a main oscillator configured to generate oscillation signals of a frequency corresponding to a control voltage, and an injection locking oscillator configured to generate division signals synchronized with the oscillation signals by dividing the oscillation signals, wherein a free running frequency of the injection locking oscillator is set according to the frequency of the oscillation signals.

Abstract: The described embodiments provide a configurable pulse generator circuit. More specifically, the described embodiments include a pulse generator circuit; an inverting difference oscillator (IDO) enabling circuit coupled to the pulse generator circuit; and a disable signal coupled to the IDO enabling circuit. When the disable signal is asserted, the IDO enabling circuit is disabled and the pulse generator circuit is configured as a pulse generator. In contrast, when the disable signal is deasserted, the IDO enabling circuit is enabled and the pulse generator circuit is configured as part of an IDO.

Abstract: Systems and methods for increasing the frequency range of an output signal generated by a VCO, where one or more variable delay units are incorporated into an interpolative VCO to decrease the minimum frequency at which the VCO oscillates. In one embodiment, the VCO includes a ring of serially connected inverters, a set of bypass circuits and a set of variable delay units. The bypass circuits are coupled to the ring of serially connected inverters to bypass one or more of the serially connected inverters when enabled. Each variable delay unit delays signal transitions at the input of a corresponding one of the serially connected inverters by a variable amount. The variable delay units may be positioned in series with the ring of inverters, in parallel with the bypass paths, or in parallel with corresponding inverters in the ring of inverters.

Abstract: An integrated circuit incorporating a bias circuit for a current-controlled oscillator (ICO) with improved power supply rejection ratio (PSRR) is described. The bias circuit for the ICO includes two error amplifiers. The first error amplifier regulates the bias voltage, VBN, referenced to a ground supply (GND). The second error amplifier regulates the bias voltage, VBP, referenced to a positive power supply (VDD). The VBP and VBN bias voltages have improved PSRR relative to conventional ICO bias circuits for noise injected into VDD and GND.

Abstract: The present invention offers an object proximity detector and object position detector. The variation of frequency of an oscillator is used to detect the proximity of an object to a sensor plate. The dependence of the sensitivity of the detector on the area of the sensor plate is reduced by conducting the sensor plate to two capacitors in series. The conducting wire of the sensor plate can be flexible without causing error detection. In the sensor element of the sensor oscillator, a resistor is connected at one terminal of the sensor plate to form a high pass filter. A resistor and a capacitor are added to the sensor oscillator to form a low pass filter. The high pass filter is used to reduce the low frequency electromagnetic interference. The low pass filter is used to reduce the high frequency electromagnetic interference.

Abstract: A multi-phase oscillator includes a plurality of ring oscillators (21) each having a plurality of output ports and each formed by connecting an odd number of inverters (20) in a ring, and a plurality of resistance elements (30) coupling the output ports between the plurality of ring oscillators (21) so that all of the plurality of ring oscillators (21) operate at an identical frequency while keeping a desired phase relationship. The number of the ring oscillators (21) is not limited to an odd number but may be an even number. The multi-phase oscillator changes the state of a succeeding node of a phase coupling to accord with the state of a preceding node of the phase coupling by using the resistance elements (30) as phase coupling devices. If resistors are used as the resistance elements (30), the phase output accuracy greatly improves and high frequency oscillation is possible.

Abstract: An integrated circuit 2 is provided with one or more monitoring circuits 14, 16, 18, 20 in the form of ring oscillators 22. These ring oscillators 22 include a plurality of tri-state inverters 24, 26, 28 containing a current-limiting transistor 42 operating in a leakage mode. The leakage current through the transistor 42 is dependent upon an operating parameter of the integrated circuit 2 being monitored. Accordingly, the oscillation frequency Fosc of the ring oscillator 22 varies in dependence upon the operating parameter to be measured.

Abstract: A VCO circuit includes: a control portion to which a first voltage is inputted and from which a second voltage corresponding to the first voltage is outputted; a current source portion to which the second voltage is inputted and from which a current corresponding to the second voltage is outputted; and an oscillator circuit to which the current is inputted and from which a signal with a frequency in accordance with the current is outputted. The control portion includes an adjusting circuit which changes the second voltage in conjunction with fluctuation of a power supply voltage. Accordingly, fluctuation of the frequency Fo of an output signal of the VCO circuit can be suppressed even when the power supply voltage of the VCO circuit fluctuates.

Abstract: A phase locked loop (PLL) and a voltage controlled oscillator (VCO) thereof are provided. The VCO includes a ring oscillator circuit and a control circuit. The ring oscillator circuit is used for providing an output clock signal; and the control circuit is coupled to the ring oscillator circuit, and used for receiving an output voltage to respectively provide a first voltage-frequency gain and a second voltage-frequency gain so as to control a frequency of the output clock signal provided by the ring oscillator circuit, wherein the first voltage-frequency gain is larger than the second voltage-frequency gain.

Abstract: An oscillator includes a control circuit and a ring of symmetric load delay cells. Each delay cell includes two novel symmetric loads. Each load involves a level shift circuit and a diode-connected transistor coupled in parallel with a current source-connected transistor. The control circuit converts an oscillator input signal into bias control signals that in turn control the effective resistance of the symmetric loads such that delays through the delay cells are a function of the input signal. The control circuit uses a symmetric load replica in a control loop to control the level shift circuits of the delay cells such that the oscillating delay cell output signals have a constant amplitude. In a first advantageous aspect, due to the constant amplitude, the oscillator is operable over a wide frequency range. In a second advantageous aspect, the oscillator input signal to output signal oscillation frequency has a substantially linear relationship.

Abstract: In a coupled ring oscillator including q ring oscillators each including p inverter circuits connected together to form a ring shape, and a phase coupling ring including (p×q) phase coupling circuits each of which is configured to couple an output of one of the p inverter circuits of one of the q ring oscillators to an output of one of the p inverter circuits of another one of the q ring oscillators in a predetermined phase relationship, and which are connected together to form a ring shape, for at least one group made up of one of the p inverter circuits in each of the q ring oscillators, outputs of the q inverter circuits belonging to the at least one group are fixed in phase with one another, the q ring oscillators are caused to oscillate in the in-phase fixed state, and then, the outputs of the q inverter circuits are released from the in-phase fixed state.

Abstract: A variable frequency oscillating circuit has an oscillating circuit that undergoes an oscillation operation. The oscillating circuit has at least one inverter and at least one capacitor forming a circuit in a ring oscillator configuration. A current circuit outputs a current based on a frequency control signal controlling a frequency of a clock signal output from the oscillating circuit. A pulse generating circuit generates a pulse when the frequency control signal is switched from low to high and from high to low. The oscillating circuit stops an oscillation operation by stopping a charge/discharge operation of the at least one capacitor when the pulse is generated by the pulse generating circuit.

Abstract: A frequency-tunable arrangement comprises a resonance circuit having a capacitive part that is tunable throughout a capacitance range. A plurality of amplifiers is coupled to the resonance circuit so as to form an oscillation loop. At least one of the amplifiers is a switchable amplifier that is switchable between an active state and an idle state. The switchable amplifier causes a capacitance variation in parallel to the capacitive part of the resonance circuit when switched between the active and the idle state. The switchable amplifier is arranged so that the capacitance variation substantially corresponds to the capacitance range throughout which the capacitive part can be tuned.

Abstract: A current controlled, phase locked loop device includes a phase detector configured to compare a reference frequency to an output frequency of a current controlled oscillator (ICO), a charge pump coupled to the phase detector and a low pass filter coupled to the charge pump. A voltage to current (V to I) converter is coupled to the low pass filter, providing an output current for integral control of the ICO. A control circuit is coupled to the ICO, and receives increment and decrement outputs of the phase detector, wherein the control circuit is configured to provide proportional control of the ICO through an amount of bias current applied thereto.

Abstract: Four stochastic resonators 20-1 to 20-4 outputting a pulse signal in accordance with a stochastic resonance phenomenon are unidirectionally coupled in a ring-like form to constitute a fluctuation oscillator 10. When a signal output from each of the stochastic resonators 20-1 to 20-4 is successively transmitted in the stochastic resonators 20-1 to 20-4 coupled in a ring-like form, the output timings at each stochastic resonator 20 are synchronized with each other due to a cooperation phenomenon between the stochastic resonators 20-1 to 20-4, so that each stochastic resonator 20 is self-excited to oscillate at a constant period of time.

Abstract: A voltage-controlled oscillator includes a delay circuit. The delay circuit includes a first buffer inverter which receives one of the differential input signal and outputs an other of the differential output signal, a second buffer inverter which receives the other of the differential input signal and outputs the one of the differential output signal, a first latch inverter which receives the one of the differential output signal, and includes an output connected to an output of the first buffer inverter, and a second latch inverter which receives the other of the differential output signal, and includes an output connected to an output of the second buffer inverter. The first latch inverter and the first buffer inverter receive a current produced from different voltage-current conversion circuits.

Abstract: Disclosed herein is a synchronous oscillator including at least one injection circuit having an injection signal input terminal, an internal clock signal input terminal, and a clock output terminal, and at least one delay circuit cascaded to the injection circuit.

Abstract: A phase noise minimization circuit is disclosed, to be used in a voltage-controlled oscillator (VCO) circuit embedded in a feedback system. The phase noise minimization circuit includes a noise power meter to analyze the control voltage fed into the VCO by the feedback system and determine its voltage noise power. Since the VCO is controlled by the feedback system, the control voltage noise power is also an indication of the VCO phase noise power for frequencies offset within the bandwidth of the feedback system. The VCO has several parameters that can be adjusted to affect its phase noise. A minimization algorithm generates the optimum set of parameters that minimize the control voltage noise power (and thus the VCO phase noise power), and sends them to the oscillator. The phase noise minimization circuit may be used in a variety of applications, particularly in phase-locked loop and frequency-locked loop VCOs.

Abstract: In a voltage-controlled ring oscillator, one or more controllable current sources generate a bias current in response to a tuning voltage. Any of several features can be included to promote frequency tuning linearity. In accordance with one feature, the ring oscillator circuit transistors can be sized relative to one another to skew the rise and fall times of the ring oscillator output signal with respect to one another. In accordance with another feature, a peak limiter can limit the oscillation amplitude in response to the bias current. In accordance with still another feature, a controllable bias current source can include a voltage-to-current converter and one or more groups of digitally controlled current source transistors.

Abstract: The semiconductor integrated circuit includes a first oscillator, a second oscillator (PLL), a third oscillator (ring oscillator), a selector that switches, in turn, based on a clock of the third oscillator, and outputs a clock of the first oscillator or a clock of the second oscillator, and a determination circuit that counts up or counts down the clock output from the selector, based on the clock of the third oscillator, determines the correspondence of the clock output from the selector and the clock of the third oscillator, based on a result of the counting up or the counting down, and determines whether either of the clock output from the selector or the clock of the third oscillator occur an abnormal oscillation.

Abstract: A bias circuit and a voltage-controlled oscillator (VCO) thereof suitable for improving the stability of the bias circuit are provided. The bias circuit includes: an error amplifier circuit, having an inverting input terminal connected to a reference voltage; a voltage-controlled current source, having a voltage control terminal connected to a voltage output terminal of the error amplifier circuit, in which a current generated by the current source is controlled by a voltage at the voltage output terminal of the error amplifier circuit; a delay control circuit, having a current input terminal connected to the voltage-controlled current source, an output terminal connected to a non-inverting input terminal of the error amplifier circuit, and a voltage input terminal connected to a supply terminal of the control voltage, and the delay control circuit is adapted to adjust an output voltage of the delay control circuit according to a control voltage.

Abstract: A frequency divider involves a plurality of Injection-locked Ring Oscillators (ILRO). A first ILRO includes a pair of cross-coupled N-channel transistors, a pair of load resistors, an integrating capacitor, and a current injection circuit. The drain of each transistor is coupled to the gate of the other transistor. Each load resistor couples the drain of each transistor to a circuit voltage source. The integrating capacitor couples the sources of each transistor. The current injection circuit alternately opens and closes a path from the source of each transistor to circuit ground in response to an oscillatory input signal of a first frequency. In response, the voltage state at the drain of each transistor is alternately latched and toggled, generating a differential pair of oscillating signals frequency divided by two. A first and second ILRO driven in antiphase generate two differential output signals in phase quadrature.

Abstract: An electrical circuit includes a first path including even-number inverters connected in series from a first node serving as an input side to a second node serving as an output side, a second path including even-number inverters connected in series from the second node serving as an input side to the first node serving as an output side, a latch circuit providing a connection between the first node and the second node such that a logical value of the first node and a logical value of the second node are opposite to each other, and one or more control signal paths to supply one or more control signals to the latch circuit to provide and sever a connection between the latch circuit and a power supply.

Abstract: A frequency stabilizing device of an oscillator is disclosed. The frequency stabilizing device of an oscillator is used for stabilizing the frequency of an oscillator to keep the frequency in constant when input voltage is changed. The frequency stabilizing device comprises a plurality of transmission gates for receiving an input voltage and generating a current and a plurality of resistors for control the value of the current, wherein the current is positive in relation to the input voltage and the frequency of the oscillator is determined by the current.

Abstract: The present invention is directed to reduce the chip area of a semiconductor integrated circuit. A semiconductor integrated circuit of the invention includes a first transistor, a second transistor disposed adjacent to the first transistor along a Y axis, and a third transistor disposed adjacent to the second transistor along an X axis. The semiconductor integrated circuit further includes a fourth transistor disposed adjacent to the third transistor along the Y axis and disposed adjacent to the first transistor along the X axis. The first to fourth transistors share a well, and an output signal of the first transistor and an output signal of the second transistor have phases opposite to each other. An output signal of the second transistor and an output signal of the third transistor have phases opposite to each other. An output of the third transistor and an output signal of the fourth transistor have phases opposite to each other.

Abstract: In a voltage controlled oscillation circuit including a cascade connection of a voltage-to-current conversion circuit (310) for generating an input voltage converted current which is a current corresponding to an input voltage and a current controlled oscillation circuit (120) of which an oscillation frequency varies according to the input voltage converted current, the voltage-to-current conversion circuit (310) includes a first current source for outputting a current in proportion to the input voltage and a plurality of second current sources for outputting a current in proportion to a voltage obtained by shifting the input voltage. Then, a current obtained by adding a current output from the first current source and currents output from the plurality of current sources is output as the input voltage converted current to the current controlled oscillation circuit (120).

Abstract: An oscillator includes a reference stage and multiple phase stages. The reference stage has a reference transistor having a gate coupled to a voltage reference and a drain coupled to a reference current source. Each phase stage includes a transistor, two current sources, a capacitor, switch, inverter, and latch. The transistor has a drain coupled to a first current source, a gate coupled to a node and a source coupled to the reference transistor's source. The capacitor and switch couple between the node and ground. The second current source couples to the node. The transistor's drain couples to the inverter's input. The inverter's output couples to the latch's set input. The latch's output couples to the switch. The inverter output also couples to the reset input of a subsequent phase stage's latch. The inverter output for a last stage couples to the reset input of a first stage latch.

Abstract: A microelectronic die including a CMOS ring oscillator thereon, and a method of using the same. The microelectronic die includes: a die substrate; and a plurality of CMOS ring oscillators on the die substrate, the ring oscillators being disposed at regions of the die substrate that are adapted to exhibit differing strain responses to package-included stress with respect to one another. A method of determining mechanical stress on a die which includes providing a die substrate in a CMOS ring oscillator on a die substrate. A frequency counter is coupled to the ring oscillator to measure a frequency of the ring oscillator to generate a frequency data signal therefrom. The frequency data signal is used to determine the mechanical stress on the die at a location of the ring oscillator.

Abstract: One embodiment in accordance with the invention is a method that can include utilizing a ring oscillator module to determine a process corner of an integrated circuit as fabricated that includes the ring oscillator module. The impedance of an output driver of the integrated circuit can be altered based on the process corner of the integrated circuit as fabricated.

Abstract: A device (1) for generating a random bit sequence has a digital ring oscillator circuit (2) having at least one first feedback path (R8) and one second feedback path (R14). To this end, a changeover is performed between the feedback paths (R8, R14) at times which can be predetermined, and a random signal (OS) having a random level history can be tapped at an output node (4) of the ring oscillator circuit (2).

Abstract: It is an object of the present invention to solve a problem that malfunction of communication is generated by varying a frequency of a clock due to noise from outside in a case where there is no supplied signal in a circuit which performs negative feedback control so that the supplied signal and the feedback signal can maintain a fixed phase relationship between the signals. The present invention provides a configuration including a PLL circuit and an oscillator circuit, where a switch for switching an output between a signal from the PLL circuit and a signal from the oscillator circuit to the signal output portion is provided to switch from a connection to the PLL circuit to a connection to the oscillator circuit in a case where there is no received signal.

Abstract: One delay circuit is inserted in open loop inside a clock recovery circuit for improving the accuracy of clock recovery. One oscillator signal ?(0) to ?(2i?1) is provided with a basic Step of Time. A rational number of Step of Time corresponding to a bit-duration is measured inside a received flow of bits. The oscillator signal ?(0) to j(2i?1) is transformed into a clock signal CK having active edges of said clock signal in phase with at least one oscillator signal ?(0) to ?(2i?1), two consecutive active edges being separated by a time duration proportional to the integer part of the number of Step of Time. A time delay is computed proportional to the fractional part of the number of Step of Time. The next active edge of the clock signal CK is delayed of said computed delay.

Abstract: A ring-based multi-push voltage-controlled oscillator (VCO) generates a multi-push output signal using a control voltage. The ring-based multi-push VCO includes a plurality of delay cells, a plurality of buffer amplifiers, and a bias unit. The delay cells connect each other in sequence to form a ring structure, and each delay cell connects with the respective buffer amplifier. The bias unit connects with the buffer amplifiers to output the multi-push output signal. The control voltage supplied to the delay cells is utilized to control the frequency of the multi-push output signal, and the ring structure formed by the delay cells is to multiply the frequency of the multi-push output signal to increase the frequency tuning range.

Abstract: A coupled ring oscillator includes n ring oscillators (20) each including m inverter circuits (10), and a phase-coupling loop (40) in which m×n phase-coupling circuits (30), each of which couples signal phases at two points in a certain phase mode, are connected with each other to form a loop. Connection points at which the inverter circuits (10) are connected with each other and the connection points at which the phase-coupling circuits (30) are connected with each other are connected bijectively; and each of the inverter circuits (10) is connected between two points that divide the phase-coupling circuits (30) into two parts at a certain ratio.

Abstract: Equal numbers of variable capacitance elements, capacitance values of which are separately controlled according to a logic value of a corresponding bit of a delay control signal that is in a one-to-one relation with an oscillation frequency, are connected in parallel among differential outputs of all delay circuits excluding a differential non-inverting delay circuit at the end, which extracts a frequency signal to the outside. Bits of the delay control signal are connected in a one-to-one relation to the equal numbers of variable capacitance elements arranged on output sides of all the delay circuits, in a relation in which delay control signals continuous in terms of frequency are not connected to the equal number of variable capacitance elements arranged on an output side of one of the delay circuits.

Abstract: A voltage controlled oscillator circuit includes first and second power rails, a control voltage rail, an input terminal, and an output terminal. A plurality of domino stages are series connected in a ring, with each of the domino stages being connected across the first and second power rails and being responsive to the control voltage rail. A plurality of feedback paths is provided with each path connected to enable one of the plurality of domino stages to input a feedback output signal to a preceding serially connected domino stage. A reset signal is asserted to place the domino stages in a post charge state and deasserted to allow the domino stages to begin producing an oscillating signal.

Abstract: An open-loop switching amplifier achieves synchronous operation using a ring oscillator based upon a tapped delay line. A counter is clocked from the ring oscillator, periodically comparing incoming more significant data to the value of the counter to form a pulsewidth modulated output waveform. Modulating the effective width of the output waveform in incremental delay line taps is equivalent to incoming less significant data. This technique then effects time-period summation of coarse and fine resolution clocked data.