Ring Oscillators Patents (Class 331/57)
  • Patent number: 8410858
    Abstract: Electronic circuitry comprising operational circuits of active switching type requiring timing signals, and conductive means for distributing said timing signals to the operational circuits, wherein the timing signal distribution means includes a signal path that has different phases of a drive signal are supplied via active means at different positions about the signal path where that path exhibits endless electro-magnetic continuity without signal phase inversion or has interconnections with another signal path having different substantially unidirectional signal flow where there is no endless electromagnetic continuity between those signal paths and generally has non-linear associated circuit means where the signal path is of a transmission line nature.
    Type: Grant
    Filed: February 10, 2012
    Date of Patent: April 2, 2013
    Assignee: Analog Devices, Inc.
    Inventor: John Wood
  • Patent number: 8400818
    Abstract: A voltage-controlled oscillator includes an oscillating unit configured to output first and second output clock signals at first and second nodes, respectively, the first and second output clock signals having a frequency that is variable in response to a control voltage. An active element unit connected to the oscillating unit is configured to maintain oscillation of the oscillating unit. A bias current generating unit connected to the active element unit at a bias node provides a bias current to the bias node and is adapted to adjust the bias current in response to a control code. First and second capacitor blocks connected to the oscillating unit and the active element unit provide first and second load capacitances, respectively, to the first and second nodes, respectively, in response to the control code.
    Type: Grant
    Filed: May 17, 2011
    Date of Patent: March 19, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ho-Seok Seol, Seung-Jun Bae, Sang-Hyup Kwak
  • Patent number: 8395455
    Abstract: A ring oscillator includes a plurality of inverting delay units serially connected in a form of a ring. Each of the inverting delay units receives an input signal and generates an output signal, and each of the inverting delay units includes a buffer and a delay circuit. The buffer has an input terminal and an output terminal. The input terminal receives the input signal, and the output terminal generates a buffered input signal. The delay circuit serves to provide a first time delay and a second time delay. Besides, according to a voltage level of the buffered input signal, the delay circuit provides a first reference voltage to generate the output signal after the first time delay or provides a second reference voltage to generate the output signal after the second time delay.
    Type: Grant
    Filed: October 14, 2011
    Date of Patent: March 12, 2013
    Assignee: United Microelectronics Corp.
    Inventor: Chien-Liang Chen
  • Patent number: 8395454
    Abstract: A circuit for producing a synchronized output of multiple ring oscillators is disclosed. In one embodiment, the circuit includes a first ring oscillator configured to generate a first periodic signal and a second ring oscillator configured to generate a second periodic signal. The circuit may further include a selection unit coupled to receive the first periodic signal and the second periodic signal. The selection unit is configured to convey a first clock edge into each of the first and second ring oscillators responsive to a most recently received rising edge from one of the first and second periodic signals. The selection unit is further configured to convey a second clock edge into each of the first and second ring oscillators responsive to a most recently received falling edge from one of the first and second periodic signals, wherein the first and second clock edges are opposite in direction.
    Type: Grant
    Filed: May 13, 2011
    Date of Patent: March 12, 2013
    Assignee: Oracle International Corporation
    Inventor: Timothy Horel
  • Publication number: 20130057352
    Abstract: Oscillator circuitry having a switching inverting amplifier arranged in a ring oscillator configuration of at least two stages. A bias generator for supplying the amplifiers of neighboring stages, is responsive to an enable signal to supply the amplifiers only when the enable signal is asserted. A first pair of transistors, coupled to an input of one of the amplifiers and the other coupled to an output of the amplifier, the transistors being driven in common by the enable signal such that when the enable signal is deasserted the transistors of the pair are turned on to impose conflicting levels at the input and the output such that the amplifier is forced to switch.
    Type: Application
    Filed: August 29, 2012
    Publication date: March 7, 2013
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Jin Liang, David Grant, Larry Wofford
  • Publication number: 20130049874
    Abstract: A ring oscillator includes (2N+1) inverting delay circuit cells, and each delay circuit cell has an input port and an output port, where N is an integer larger than zero. Each of these (2N+1) inverting delay circuit cells receives a control voltage, and all of the (2N+1) inverting delay circuit cells are electrically connected with each other in series. Furthermore, the input port of one of the (2N+1) inverting delay circuit cells is electrically connected with the output port of an adjacent delay circuit cell of the (2N+1) inverting delay circuit cells.
    Type: Application
    Filed: August 27, 2012
    Publication date: February 28, 2013
    Inventors: Ying-Chieh HO, Yu-Sheng Yang, Chau-Chin Su
  • Patent number: 8378753
    Abstract: An oscillator circuit includes a circuit loop and multiple current sources. The circuit loop includes an output having the oscillating signal. The multiple current sources are turned on independently of a phase of the oscillating signal. The current sources control magnitudes of both charging current and discharging current at nodes of the circuit loop, including the output. Relative magnitudes of different current sources determine a frequency of the oscillating signal.
    Type: Grant
    Filed: May 7, 2010
    Date of Patent: February 19, 2013
    Assignee: Macronix International Co., Ltd.
    Inventor: Tien-Yen Wang
  • Patent number: 8378754
    Abstract: Multiple multi-stage delay circuits each have n (n is an integer) output terminals. The multi-stage delay circuits each apply delay times to a corresponding input signal, and output, via n output terminals, n delayed signals to which different delay times have been applied. Multiple inverters invert the respective input signals. The multiple multi-stage delay circuits and multiple inverters are alternately connected in the form of a ring.
    Type: Grant
    Filed: January 30, 2009
    Date of Patent: February 19, 2013
    Assignee: Advantest Corporation
    Inventor: Kazuhiro Yamamoto
  • Publication number: 20130037697
    Abstract: A ring oscillator circuit causing a pulse signal to circulate around a circle to which an even number of inverting circuits are connected in a ring, wherein one of the inverting circuits is a first starting inverting circuit, which drives a first pulse signal according to a control signal, another of the inverting circuits is a second starting inverting circuit, which drives a second pulse signal based on a leading edge of the first pulse signal, still another is a third starting inverting circuit, which drives a third pulse signal based on the leading edge of the first pulse signal after the second pulse signal is driven, and the first to third starting inverting circuits are arranged within the circle of the inverting circuits in order of the third, second, and first pulse signals in traveling directions of the pulse signals.
    Type: Application
    Filed: July 6, 2012
    Publication date: February 14, 2013
    Applicant: OLYMPUS CORPORATION
    Inventor: Shuichi Kato
  • Patent number: 8373511
    Abstract: An oscillator circuit and method for gain and phase noise control. A gain and phase noise controlled oscillator circuit includes a variable electronic oscillator and a tuning loop circuit. In operation, the variable electronic oscillator generates a clock signal and has a clock signal frequency that is controlled by a sense voltage received by the variable electronic oscillator or by one or more capacitive loads coupled to the variable electronic oscillator. Further, the tuning loop circuit is coupled to the variable electronic oscillator and compares the sense voltage to a control voltage received by the tuning loop circuit and produces one or more correction signals based on the comparison, where the one or more capacitive loads change capacitance based on the one or more correction signals.
    Type: Grant
    Filed: October 15, 2010
    Date of Patent: February 12, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Ajay Kumar, Xiao Pu, Krishnaswamy Nagaraj
  • Patent number: 8373512
    Abstract: A signal generator provides a plurality of oscillating signals, whereby each oscillating signal has a different peak voltage and has a predictable and consistent phase relationship with the other oscillating signals. The signal generator includes a plurality of stacked oscillators arranged between two reference voltages, such that each oscillator in the stack generates an oscillating signal having a different peak voltage. Each oscillator stage in a designated oscillator includes a transistor that is connected to a transistor of a corresponding stage in another oscillator. This arrangement of the oscillators provides for charge transfer between the corresponding stages to provide for similar voltage swings in each oscillating signal, as well as to provide for predictable phase relationship between the oscillating signals.
    Type: Grant
    Filed: December 22, 2010
    Date of Patent: February 12, 2013
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Visvesh S. Sathe
  • Patent number: 8373482
    Abstract: A method of programming a ring oscillator for use as a temperature sensor comprises selecting an initial number of delay elements for use in a ring oscillator. The method further comprise starting a system clock counter and counting pulses of the ring oscillator until the system clock counter reaches a programmed value. The method also comprises determining whether a number of counted ring oscillator pulses is between lower and upper count thresholds and changing the number of delay elements for the ring oscillator as a result of the number of counted ring oscillator pulses being less than the lower count threshold or greater than the upper count threshold.
    Type: Grant
    Filed: January 13, 2011
    Date of Patent: February 12, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Sam G. Sabapathy, Christine J. Chang
  • Publication number: 20130027099
    Abstract: Systems, methods and circuitry useful for adjusting a periodic signal such as with a voltage controlled oscillator or a delay line. In one series of embodiments, circuits and methods are provided for controlling current flow through first and second parallel paths where an impedance device in one path emulates the impedance characteristics of a different device in the other path. A phase or frequency characteristic of the periodic signal may be adjusted by alternate switching of current through the two paths.
    Type: Application
    Filed: July 9, 2012
    Publication date: January 31, 2013
    Inventors: Robert Wang, Antonios Pialis, Rajeevan Mahadevan, Navid Yaghini, Rafal Karakiewicz, Raymond Kwok Kei Tang, Sida Shen
  • Publication number: 20130027139
    Abstract: The embodiments described herein provide a voltage controlled oscillator (VCO). The VCO may include, but is not limited to a voltage-to-current converter configured to receive a control voltage and to convert the control voltage to a current, a current bias circuit coupled to the voltage-to-current converter and configured to receive frequency band select digital inputs and to bias the current generated by the voltage-to-current converter based upon the band select inputs, and a ring oscillator coupled to receive the biased current and to output an oscillating signal based upon the biased current.
    Type: Application
    Filed: July 27, 2011
    Publication date: January 31, 2013
    Applicant: GLOBALFOUNDRIES Inc.
    Inventors: Sreenivasa Chalamala, Dieter Hartung
  • Publication number: 20130027140
    Abstract: The described systems and methods can facilitate examination of device parameters including analysis of relatively dominant characteristic impacts on delays. In one embodiment, at least some coupling components (e.g., metal layer wires, traces, lines, etc.) have a relatively dominate impact on delays and the delay is in part a function of both capacitance and resistance of the coupling component. In one embodiment, a system comprises a plurality of dominate characteristic oscillating rings, wherein each respective one of the plurality of dominate characteristic oscillating rings includes a respective dominate characteristic. Additional analysis can be performed correlating the dominate characteristic delay impact results with device fabrication and operation.
    Type: Application
    Filed: June 20, 2012
    Publication date: January 31, 2013
    Applicant: NVIDIA CORPORATION
    Inventors: Wojciech Jakub Poppe, Ilyas Elkin, Puneet Gupta
  • Patent number: 8362848
    Abstract: A supply-regulated VCO exhibits reduced or no supply sensitivity peaking. The VCO includes an oscillator whose supply current is regulated to control the oscillating frequency of the oscillator. A VCO input signal controls the supply current so that there is a relationship between the input signal and the oscillator output frequency. Power supply noise that might otherwise affect oscillator operation is shunted from a supply current input lead of the oscillator to ground by a bypass capacitor. In one example, an auxiliary circuit supplies an auxiliary supply current to the oscillator, thereby reducing the amount of supply current a supply regulation control loop circuit must supply. In another example, a supply regulation control loop circuit supplies a control current to a main oscillator, but the bypass capacitor is not coupled to this oscillator but rather is coupled to a slave oscillator that is injection locked to the main oscillator.
    Type: Grant
    Filed: April 7, 2011
    Date of Patent: January 29, 2013
    Assignee: QUALCOMM Incorporated
    Inventors: Ashwin Raghunathan, Marzio Pedrali-Noy, Sameer Wadhwa
  • Patent number: 8362844
    Abstract: A delay circuit includes a delay unit having a first and a second power supply terminals, a pair of differential signal input terminals and a pair of differential signal output terminals. The signals entered to the pair of differential signal input terminals are delayed and output at the pair of differential signal output terminals. The delay circuit also includes a current controller that exercises control to cause a current of a current source, controlled by a current control terminal, to flow through the first and second power supply terminals of the delay unit. The delay circuit also includes a voltage controller that exercises control to provide for a constant potential difference between the first and the second power supply terminals (FIG. 1).
    Type: Grant
    Filed: December 21, 2010
    Date of Patent: January 29, 2013
    Assignee: Renesas Electronics Corporation
    Inventor: Fumio Nakano
  • Publication number: 20130021107
    Abstract: Component characteristics analysis systems and methods are described. In one embodiment, a ring oscillator comprises: at least one inversion stage operable to cause a signal transition; a target component that has an increased comparative impact or influence on a signal transition propagation in the ring oscillator; and an output component for outputting an indication of the impact the target component has on the signal transition. The target component can include a plurality of vias from one metal layer to another metal layer. The plurality of vias from one metal layer to another metal layer can be configured in a cell. The vias can correspond to a via layer. In one exemplary implementation, the output is coupled to an analysis component. The analysis component can include correlation of the via resistance into a wafer variations and generate a wafer map. The analysis component can include correlation of the via resistance into a wafer.
    Type: Application
    Filed: July 23, 2012
    Publication date: January 24, 2013
    Applicant: NVIDIA CORPORATION
    Inventors: Wojciech Jakub Poppe, Puneet Gupta, Ilyas Elkin
  • Publication number: 20130015894
    Abstract: A voltage control oscillator according to the present invention includes: a voltage-current converter circuit that converts an inputted voltage to a current according to the value of the voltage; a current mirror circuit; a ring oscillator including differential inverters connected in multiple stages; an inverting amplifier; and a buffer. The ring oscillator outputs, from each of the differential inverters, a signal amplitude-limited by a “current converted by the voltage-current converter circuit and the current mirror circuit” and a “voltage applied from the inverting amplifier” and the ring oscillator outputs an oscillatory frequency in response to the output signal.
    Type: Application
    Filed: July 12, 2011
    Publication date: January 17, 2013
    Inventor: Kunihiko KOUYAMA
  • Patent number: 8350628
    Abstract: A computing device is disclosed comprising digital circuitry including a critical path circuit, and a gate speed regulator. A ring oscillator generates an oscillation frequency, and dither circuitry periodically adjusts a number of inverter elements in the ring oscillator in order to adjust an average propagation delay of the ring oscillator relative to a propagation delay of the critical path circuit. A comparator compares the oscillation frequency to a reference frequency to generate an error signal, and an adjustable circuit, responsive to the error signal, adjusts at least one of a supply voltage and a clocking frequency applied to the digital circuitry.
    Type: Grant
    Filed: February 15, 2011
    Date of Patent: January 8, 2013
    Assignee: Western Digital Technologies, Inc.
    Inventor: George J. Bennett
  • Patent number: 8350629
    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.
    Type: Grant
    Filed: August 20, 2009
    Date of Patent: January 8, 2013
    Inventors: Ronald A. Parrott, Allen A. Sweet
  • Publication number: 20130002361
    Abstract: A ring oscillator that is more insensitive to power supply ripple utilizes an amplifier circuit having a first input coupled to a reference voltage. A current is generated that represents a control voltage supplied to the oscillator control circuit. That current is mirrored and supplied as a control current to the oscillator. An amplifier is used in a feedback loop to ensure that incremental variations in source to drain voltage of a first transistor of the current mirror is present in a second transistor of the current mirror to make the control current more immune to supply ripple.
    Type: Application
    Filed: June 30, 2011
    Publication date: January 3, 2013
    Inventors: Abdulkerim L. Coban, Ravi Kummaraguntla
  • Patent number: 8339208
    Abstract: A tunable multiphase ring oscillator includes a plurality of stages connected in series in a ring structure, where each stage generating a stage output from a stage input. Each stage of the tunable multiphase ring oscillator includes a plurality of trans-conductance cells, each generating an output from at least one portion of the stage input. Each stage further includes at least one phase shifting module for imparting at least one phase shift to the at least one portion of the stage input, an oscillator unit for generating the stage output from a combination of the plurality of outputs, and means for varying at least one of the plurality outputs so as to adjust a phase of the stage output.
    Type: Grant
    Filed: June 8, 2010
    Date of Patent: December 25, 2012
    Assignee: The Hong Kong University of Science and Technology
    Inventors: Howard Cam Luong, Sujiang Rong
  • Publication number: 20120319784
    Abstract: A generator of very short pulses where a cascade of inverters of arbitrary length characterized in that said inverters are adapted to produce pulses on their power supply line instead of their usual output.
    Type: Application
    Filed: June 13, 2012
    Publication date: December 20, 2012
    Applicant: ECOLE POLYTECHNIQUE FEDERALE DE LAUSANNE (EPFL)
    Inventors: Edmund James COLLI-VIGNARELLI, Catherine DEHOLLAIN, Jean-Yves LE BOUDEC
  • Patent number: 8330548
    Abstract: A novel and useful apparatus and related method for on-chip measurement of the clock to output delay of a latch within an integrated circuit. The delay measurement mechanism enables measuring the time delay from the transition of the clock input to the data output of a latch. The output delay of the on-chip latch is measured by making the latch delay part of a ring oscillator and measuring its frequency of oscillation. A latch based delay stage is used to construct the ring oscillator in which a delayed short pulse derived from the input edge is used as the trigger for the latch. The latched ring oscillator mechanism of the invention can be used to measure the clock to output (C2Q) delay of on-chip latch devices.
    Type: Grant
    Filed: August 20, 2010
    Date of Patent: December 11, 2012
    Assignee: International Business Machines Corporation
    Inventor: Israel A. Wagner
  • Patent number: 8324974
    Abstract: A computing device is disclosed comprising digital circuitry fabricated on a multi-layer integrated circuit including a first layer and a second layer, and a multi-layer ring oscillator operable to generate a propagation delay frequency representing a propagation delay of the integrated circuit, wherein the multi-layer ring oscillator comprises a first interconnect fabricated on the first layer and a second interconnect fabricated on the second layer. The propagation delay frequency is compared to a reference frequency to generate a frequency error, and at least one of a supply voltage and a clocking frequency applied to the digital circuitry is adjusted in response to the frequency error.
    Type: Grant
    Filed: December 17, 2010
    Date of Patent: December 4, 2012
    Assignee: Western Digital Technologies, Inc.
    Inventor: George J. Bennett
  • Patent number: 8305149
    Abstract: A semiconductor circuit apparatus having a clock oscillating circuit includes a first inverter circuit having a power supply terminal connected to a power supply potential via a first power supply potential connection transistor and a ground terminal connected to a ground potential via a first ground potential connection transistor, an inverter circuit block having a second inverter circuit connected to the power supply potential via a second power supply potential connection transistor and to the ground potential via a second ground potential connection transistor and connected to the first inverter circuit in parallel and a selection circuit block that outputs a power supply potential connection signal to any one of gate terminals of the first and second power supply potential connection transistors and a ground potential connection signal to any one of gate terminals of the first and second ground potential connection transistors.
    Type: Grant
    Filed: September 18, 2009
    Date of Patent: November 6, 2012
    Assignee: Fujitsu Limited
    Inventor: Itsumi Sugiyama
  • Publication number: 20120274408
    Abstract: Disclosed is a semiconductor integrated circuit device that includes a ring oscillator circuit, performs a proper oscillation operation, and expands the range of oscillation frequency variation. The ring oscillator circuit includes, for instance, plural differential amplifier circuits. MOS transistors are respectively added to input nodes of a differential pair of the differential amplifier circuits. Further, gate control circuits are incorporated to control the gates of the MOS transistors, respectively. The gate control circuits cause the MOS transistors to function as an amplitude limiter circuit in mode 3, exercise control to turn off the amplitude limiter circuit in mode 2, and use the amplitude limiter circuit to start oscillation in mode 1.
    Type: Application
    Filed: July 11, 2012
    Publication date: November 1, 2012
    Applicant: RENESAS ELECTRONICS CORPORATION
    Inventor: Takahiro KATO
  • Publication number: 20120274407
    Abstract: A method and apparatus for supplying independently switched, regulated power to a plurality of loads is disclosed.
    Type: Application
    Filed: July 9, 2012
    Publication date: November 1, 2012
    Inventors: Roberto Nonis, Nicola Da Dalt
  • Patent number: 8294525
    Abstract: Apparatuses and methods are provided relating to a voltage controlled oscillator (VCO) based on current starved inverting delay stages; wherein in each stage a PMOS transistor as header and an NMOS transistor as footer are used with their gate-to-source voltages always equal to analog control voltage. The analog control voltage is also used as the supply voltage of the oscillator. An exemplary apparatus includes a VCO of n stages, where n is an odd number and where each stage includes a current starved inverter where the analog control voltage is also used as the supply voltage of each delay stage.
    Type: Grant
    Filed: June 18, 2010
    Date of Patent: October 23, 2012
    Assignee: International Business Machines Corporation
    Inventors: John Francis Bulzacchelli, Zeynep Toprak Deniz, Daniel Joseph Friedman, Shahrzad Naraghi, Alexander V Rylyakov
  • Publication number: 20120262240
    Abstract: A ring oscillator has a plurality of elementary units connected in cascade and linked in order to make a chain with the respective output terminals connected to the input terminals of the successive elementary units of the chain, the elementary units being crossed by a cyclic signal during a time period of activation, each of said elementary units comprising an auxiliary recovery terminal for temporarily resetting each elementary unit during each loop of said cyclic signal, said auxiliary recovery terminal being connected to an output terminal of a successive elementary unit of the chain.
    Type: Application
    Filed: April 20, 2012
    Publication date: October 18, 2012
    Applicant: STMICROELECTRONICS S.R.L.
    Inventors: Giovanni Cremonesi, Roberto Giorgio Bardelli, Silvio Fornera
  • Patent number: 8289088
    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.
    Type: Grant
    Filed: June 30, 2009
    Date of Patent: October 16, 2012
    Assignee: Oracle America, Inc.
    Inventors: Anand Dixit, Robert P. Masleid
  • Patent number: 8289086
    Abstract: A digital fractional PLL introduces an accumulated phase offset before the digital VCO using a digital accumulator to achieve the fractional part of the division ratio. To provide this phase offset, the digital accumulator can integrate a fractional component ?n. By forcing ?n to zero, the PLL becomes an integer-N PLL. A de-skew timing configuration can be used to remove any time mismatch between integer and fractional counters of the PLL. A digital PLL can merge the function of frequency generation (DVCO) and that of fractional frequency counting into the same circuit block by reusing various phases of the frequency output to generate a fractional frequency count. A digital integer PLL can include a single bit comparator, wherein the feedback loop of this PLL forces the phase difference between the reference clock signal and the feedback signal to approach zero. By changing the duty cycle of feedback signal, the frequency tracking behavior of the loop can be varied.
    Type: Grant
    Filed: March 31, 2009
    Date of Patent: October 16, 2012
    Assignee: Qualcomm Atheros, Inc.
    Inventors: Shuo-Wei Chen, David Kuochieh Su
  • Patent number: 8279015
    Abstract: A delay line of individually selectable delay elements can operate as an oscillator in an open loop mode to track process variation or drive a clock signal that varies with temperatures and voltages in the system. The delay line oscillator can also operate in a closed loop mode to match a frequency given by a tuner ratio and a reference clock. The delay line can also be used for measuring clock jitter or duty cycle.
    Type: Grant
    Filed: September 17, 2010
    Date of Patent: October 2, 2012
    Assignee: Atmel Corporation
    Inventors: Tor Erik Leistad, Frode Milch Pedersen, Fredrik Larsen
  • Patent number: 8264286
    Abstract: A first exemplary aspect of an embodiment of the present invention is a phase-locked loop circuit including: a voltage-current converter that converts a control voltage into a control current, the control voltage generated according to a phase difference between an input pulse signal and a feedback pulse signal fed back from an output side of a current controlled oscillator; the current controlled oscillator that generates an output pulse signal having a frequency according to the control current; a current detection unit that detects the control current; and a frequency range switch that switches a frequency range of the output pulse signal according to the detected control current.
    Type: Grant
    Filed: August 28, 2009
    Date of Patent: September 11, 2012
    Assignee: Renesas Electronics Corporation
    Inventor: Yoshitaka Hirai
  • Patent number: 8264287
    Abstract: An analog-to-digital converter (ADC) suitable for measuring on-die DC or low frequency analog voltages may include a ring oscillator having a group of circuit cells successively and circularly coupled. Under certain circumstances, the ring oscillator may produce an output frequency that corresponds substantially linear to the input voltage. Other embodiments may be disclosed or claimed.
    Type: Grant
    Filed: May 12, 2010
    Date of Patent: September 11, 2012
    Assignee: Intel Corporation
    Inventor: Atul Maheshwari
  • Publication number: 20120223780
    Abstract: According to one embodiment, a voltage control oscillating circuit is provided with a ring oscillator, a control current generating unit and a constant current generating unit. The ring oscillator has an odd number of inverters connected in a ring shape. The control current generating unit converts an input control voltage into a control current and to supply the control current to the ring oscillator as a first supply current. The constant current generating unit generates a constant current and to supply the generated constant current to the ring oscillator as a second supply current which is added to the control current.
    Type: Application
    Filed: September 19, 2011
    Publication date: September 6, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Go Urakawa
  • Publication number: 20120223778
    Abstract: Disclosed is a digitally controlled oscillator which includes a ring oscillator; and a variable resistance bank connected between one power node of the ring oscillator and a power supply terminal and having the resistance value varied according to the number of active bits of a control code. The frequency of an clock signal output by the ring oscillator is changed non-linearly according to the resistance value of the variable resistance bank. The frequency of the output clock signal is changed stepwise linearly according to the number of active bits of the control code.
    Type: Application
    Filed: March 2, 2012
    Publication date: September 6, 2012
    Inventors: Jongshin Shin, JaeHyun Park
  • Patent number: 8258880
    Abstract: Some embodiments disclosed herein relate to techniques for providing a relatively constant oscillation frequency. In some instances, these techniques can make use of a ring oscillator that is powered by an adaptive voltage supply. The adaptive voltage supply provides a temperature-dependent supply voltage to respective delay elements in the ring oscillator, such that the oscillation frequency of the ring oscillator is approximately constant over a predetermined temperature range. For example, if temperature increases, the supply voltage can be increased proportionally, thereby tending to limit variation in the oscillation frequency delivered by the ring oscillator.
    Type: Grant
    Filed: February 26, 2010
    Date of Patent: September 4, 2012
    Assignee: Infineon Technologies AG
    Inventors: Chin Yeong Koh, Kar Ming Yong
  • Patent number: 8258883
    Abstract: A system and method for characterizing process variations are provided. A circuit comprises a plurality of inverters arranged in a sequential loop, and a plurality of transmission gates, with each transmission gate coupled between a pair of serially arranged inverters. Each transmission gate comprises a first field effect transistor (FET) having a first channel, and a second FET having a second channel. The first channel and the second channel are coupled in parallel and a gate terminal of the first FET and a gate terminal of the second FET are coupled to a first control signal and a second control signal, respectively.
    Type: Grant
    Filed: November 12, 2009
    Date of Patent: September 4, 2012
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventors: Yi-Wei Chen, Chi-Wei Hu, Wei-Pin Changchien, Chin-Chou Liu
  • Patent number: 8258830
    Abstract: An oscillator circuit is provided. The oscillator circuit includes a gated oscillator and a calibration circuit. The gated oscillator is arranged to generate an oscillator signal according to a control signal, and receive a gating signal to align an edge of the oscillator signal with an edge of the gating signal. The calibration circuit coupled to the gated oscillator is arranged to receive a first clock signal and a second clock signal, detect an alignment operation of the gated oscillator according to the first clock signal and a second clock signal and generate the control signal according to the detected alignment operation.
    Type: Grant
    Filed: July 30, 2009
    Date of Patent: September 4, 2012
    Assignee: Mediatek Inc.
    Inventors: Che-Fu Liang, Sy-Chyuan Hwu, Yu-Hsuan Tu
  • Patent number: 8259884
    Abstract: A method and system of applying modulated carrier signals to tree networks and processing signals tapped from the tree networks to generate output signals with phase-synchronized carriers are disclosed.
    Type: Grant
    Filed: July 21, 2008
    Date of Patent: September 4, 2012
    Assignee: Blue Danube Labs, Inc.
    Inventors: Mihai Banu, Vladimir Prodanov
  • Patent number: 8253460
    Abstract: An oscillation circuit including a first transistor, a second transistor, a current source, a first inverter, and an impedance unit is disclosed. The first transistor has a first source receiving a first operation voltage, a first drain, and a first gate coupled to the first drain. The second transistor has a second source receiving the first operation voltage, a second drain, and a second gate coupled to the first gate. The current source is coupled between the first drain and a grounding voltage. The first inverter generates an oscillation signal and has a first input terminal, a first output terminal, and a first power terminal coupled to the second drain. The impedance unit is coupled between the first input terminal and the first output terminal.
    Type: Grant
    Filed: May 13, 2010
    Date of Patent: August 28, 2012
    Assignee: Princeton Technology Corporation
    Inventor: Ming Jen
  • Publication number: 20120212297
    Abstract: Apparatus and methods for wave reversing in a travelling wave oscillator are disclosed. The travelling wave oscillator includes a differential transmission line and regeneration elements connected along the differential transmission line. The differential transmission line can be used to propagate a wave traveling in either a counterclockwise or a clockwise direction. Each of the regeneration elements includes a first gain portion operable to degenerate a wave travelling in the counterclockwise direction and to regenerate a wave travelling the clockwise direction, and a second gain portion operable to degenerate a wave travelling in a clockwise direction and to regenerate a wave travelling in a counterclockwise direction.
    Type: Application
    Filed: April 30, 2012
    Publication date: August 23, 2012
    Applicant: ANALOG DEVICES, INC.
    Inventor: Gregoire Jean Marie Le Grand De Mercey
  • Publication number: 20120213358
    Abstract: A system for random number generation includes a digital oscillator circuit, which has a set of available configurations and is operative to generate a random number sequence in accordance with a current configuration selected from the set. The system further includes a randomization circuit, which is operative to produce a pseudo-random stream of values corresponding to the available configurations of the digital oscillator circuit, and to control the digital oscillator circuit to alternate among the available configurations in accordance with the pseudo-random stream of values.
    Type: Application
    Filed: February 25, 2009
    Publication date: August 23, 2012
    Inventors: Itai Dror, Leonid Minz, Boris Dolgunov, Michael Koun
  • Patent number: 8248171
    Abstract: A thermally-compensated oscillator has a current reference with an output current which relates to an ambient temperature with a first relationship, a ring oscillator having an operating frequency which relates to the ambient temperature with a second relationship, and which receives the output current of the current reference and outputs an oscillator signal, and a level shifter which receives the oscillator signal from the ring oscillator and outputs a corresponding voltage-regulated clock signal.
    Type: Grant
    Filed: January 27, 2011
    Date of Patent: August 21, 2012
    Assignee: NXP B.V.
    Inventors: Martin Bugbee, Andrew Burtt
  • Patent number: 8248176
    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.
    Type: Grant
    Filed: December 8, 2010
    Date of Patent: August 21, 2012
    Assignee: Mitsumi Electric Co., Ltd.
    Inventors: Yoichi Takano, Koichi Yamaguchi, Koichi Kuwahara
  • Patent number: 8248094
    Abstract: A test structure for gathering switching history effect statistics includes a waveform generator circuit that selectively generates a first test waveform representative of a 1SW transistor switching event, and a second test waveform representative of a 2SW transistor switching event; and a history element circuit coupled to the waveform generator circuit, the history element circuit including a device under test (DUT) therein, and a variable delay chain therein, wherein a selected one of the first and second test waveforms are input to the DUT and the variable delay chain; wherein the history element circuit determines fractional a change in signal propagation delay through the DUT between the 1SW and 2SW transistor switching events, with the fractional change in signal propagation delay calibrated with timing measurements of a variable frequency ring oscillator; and wherein the test structure utilizes only external low-speed input and output signals with respect to a chip.
    Type: Grant
    Filed: August 20, 2009
    Date of Patent: August 21, 2012
    Assignee: International Business Machines Corporation
    Inventors: Manjul Bhushan, Mark B. Ketchen
  • Patent number: 8248170
    Abstract: A stabilized quadrature oscillator providing consistently high signal quality is disclosed. The stabilized quadrature oscillator includes an iterative quadrature oscillator and a quadrature signal stabilizer. The iterative quadrature oscillator generates an iterative cosine signal and an iterative sine signal using a stabilized cosine signal and a stabilized sine signal from the quadrature signal stabilizer. The quadrature signal stabilizer generates the stabilized cosine signal and the stabilized sine signal based on an energy measure of the iterative cosine signal and the iterative sine signal. Specifically, if the energy measure is less than a low threshold then the quadrature signal stabilizer generates the stabilized sine signal and the stabilized cosine signal to have a greater magnitude than the iterative sine signal and the iterative cosine signal, respectively.
    Type: Grant
    Filed: November 22, 2010
    Date of Patent: August 21, 2012
    Assignee: Applied Micro Circuit Corporation
    Inventors: Dariush Dabiri, Dongwoon Bai, Nils Graef, Wenwei Pan
  • Patent number: 8248098
    Abstract: An apparatus and method for measuring the characteristics of a semiconductor device is disclosed. The measuring apparatus may include first to M-th (wherein M is a positive integer not less than 1) starved devices each being biased in response to a bias voltage varying in accordance with a variable first supply voltage, thereby varying an amount of current flowing through a semiconductor device included in the starved device. Interconnect lines may interconnect the first to M-th starved devices. A measuring unit measures at least one of a delay time caused by the semiconductor devices of the starved devices themselves, and a compound delay time caused by the semiconductor devices of the starved devices themselves plus a delay time caused by the interconnect lines. The measured results can be analyzed under conditions more approximate to diverse situations exhibited in practical chips in accordance with development of manufacturing processes and techniques.
    Type: Grant
    Filed: December 27, 2009
    Date of Patent: August 21, 2012
    Assignee: Dongbu HiTek Co., Ltd.
    Inventors: Chan-Ho Park, Won-Young Jung