Differential Input Patents (Class 327/65)
  • Patent number: 8497711
    Abstract: An envelope detecting method performing squelch detection on a pair of differential signal includes: by a voltage divider, providing a real-time reference signal according to a sum of the pair of differential signals; and comparing two comparison signals associated with the real-time reference signals and the pair of differential signals to generate a squelch detection signal.
    Type: Grant
    Filed: September 19, 2011
    Date of Patent: July 30, 2013
    Assignee: MStar Semiconductor, Inc.
    Inventor: Yi-Cheng Hsieh
  • Patent number: 8476934
    Abstract: Differential signal detection circuitry with an integrated reference voltage. The reference voltage is added as an offset to the output voltage, and its integration ensures that variations in the reference voltage closely track variations in the signal. Accordingly, the detection threshold for the signal being detected remains more consistent over variations in the circuit manufacturing process, power supply voltage and operating temperature.
    Type: Grant
    Filed: July 21, 2011
    Date of Patent: July 2, 2013
    Assignee: National Semiconductor Corporation
    Inventors: Arlo J. Aude, Soumya Chandramouli
  • Publication number: 20130154737
    Abstract: A comparator has a differential pair circuit, a current control circuit, and a latch. The differential pair circuit has first and second comparator transistors, and is arranged to compare a first input and a second input according to a clock signal to generate a result indicating whether a difference of the first and second inputs exceeds an internal offset. The current control circuit is coupled in series with the differential pair circuit, and configured to provide unequal abilities of drawing currents for the first and second comparator transistors.
    Type: Application
    Filed: September 12, 2012
    Publication date: June 20, 2013
    Applicant: MEDIATEK INC.
    Inventor: Yun-Shiang SHU
  • Publication number: 20130156126
    Abstract: A rail-to-rail comparator including a first comparison unit connected to a first terminal and configured to compare differential input signals to differential reference voltages; a second comparison unit connected to a second terminal and configured to compare the differential input signals to the differential reference voltages; and an output unit configured to be driven in response to a clock signal and to generate a complementary output signal according to comparison results of the first and second comparison units.
    Type: Application
    Filed: August 21, 2012
    Publication date: June 20, 2013
    Applicants: Industry-University Cooperation Foundation Sogang University, SK HYNIX INC.
    Inventors: Jin Il CHUNG, Jun Hyun CHUN, Jin Wook BURM, Dae Ho YUN
  • Patent number: 8466715
    Abstract: A comparator includes: a wide-swing operation transconductance amplifier (OTA), having first and second differential input pairs for receiving first and second differential input signals respectively, the wide-swing OTA generating first and second intermediate output voltages in comparing the first with the second differential input signals; a current switch group; a current mirror group, wherein when an input common mode voltage of the first and the second differential input signal tends to one of a first and a second reference voltage, one of the first and the second differential input pair is turned off, and the current switch group and the current mirror group compensate a current flowing through the other of the first and the second differential input pair; and a decision circuit coupled to the wide-swing OTA, for enlarging a voltage difference between the first and the second intermediate output voltage to output a voltage comparison output signal.
    Type: Grant
    Filed: January 20, 2012
    Date of Patent: June 18, 2013
    Assignee: Raydium Semiconductor Corporation
    Inventors: Yu Kuang, Shih-Tzung Chou
  • Patent number: 8461872
    Abstract: First and second devices may simultaneously communicate bidirectionally with each other using only a single pair of LVDS signal paths. Each device includes an input circuit and a differential output driver connected to the single pair of LVDS signal paths. An input to the input circuit is also connected to the input of the driver. The input circuit may also receive an offset voltage. In response to its inputs, the input circuit in each device can use comparators, gates and a multiplexer to determine the logic state being transmitted over the pair of LVDS signal paths from the other device. This advantageously reduces the number of required interconnects between the first and second devices by one half.
    Type: Grant
    Filed: August 2, 2011
    Date of Patent: June 11, 2013
    Assignee: Texas Instruments Incorporated
    Inventor: Lee D. Whetsel
  • Patent number: 8446178
    Abstract: A comparator includes: a pre-amplification module, configured to generate two amplified differential signal reference currents according to an input voltage and a reference voltage; and a differential signal obtaining module, configured to obtain a differential signal according to the two amplified differential signal reference currents. The pre-amplification module includes a differential unit, an offset unit, and an amplification unit, where the differential unit is configured to generate two direct current bias currents according to the input voltage and the reference voltage; the offset unit is configured to generate an offset current of the two direct current bias currents according to the input voltage and the reference voltage, so as to reduce magnitude of the two direct current bias currents and obtain two differential signal reference currents; the amplification unit is configured to receive the two differential signal reference currents, and amplify the two differential signal reference currents.
    Type: Grant
    Filed: December 27, 2011
    Date of Patent: May 21, 2013
    Assignee: Huawei Technologies Co., Ltd.
    Inventors: Shifu Pang, Ding Li
  • Publication number: 20130099825
    Abstract: The present disclosure provides a voltage comparator including a current source, a differential gain module and a switch module, wherein the magnitude of the current flowing through the current source is nano ampere level; the differential gain module includes a first transistor, a second transistor, a third transistor and a fourth transistor, wherein the first transistor and the second transistor are respectively connected to the current source, the third transistor and the fourth transistor form a mirror current structure, the third transistor is connected to the first transistor, and the fourth transistor is connected to the second transistor via a ninth transistor used for forming asymmetric differential gain.
    Type: Application
    Filed: November 25, 2011
    Publication date: April 25, 2013
    Inventor: Liang Cheng
  • Publication number: 20130099824
    Abstract: An apparatus is provided. The apparatus comprises backend circuitry and pairs of redundant input circuits. Each pair of redundant input circuits is configured to form a differential pair of transistors, and each redundant input circuit includes a multiplexer and a set of transistors. The multiplexer is coupled to the backend circuitry, and each transistor from the set of transistors has a first passive electrode, a second passive electrode, and a control electrode. The first passive electrode of each transistor from the set of transistors is coupled to the multiplexer, and the control electrodes from the set of transistors are coupled together.
    Type: Application
    Filed: October 25, 2011
    Publication date: April 25, 2013
    Applicant: Texas Instruments Incorporated
    Inventors: Robert F. Payne, Baher S. Haroun
  • Publication number: 20130100326
    Abstract: Disclosed herein is a comparator including: a first input sampling capacitance; a second input sampling capacitance; an output node; a transconductance (Gm) amplifier as a differential comparator section configured to receive a slope signal, a signal level of the slope signal changing with a slope, at one input terminal of the Gm amplifier via the first input sampling capacitance, and receive an input signal at another input terminal of the Gm amplifier via the second input sampling capacitance, and subject the slope signal and the input signal to comparing operation; and an isolator configured to hold a voltage of an output section of the Gm amplifier constant, the isolator being disposed between the output section of the Gm amplifier and the output node.
    Type: Application
    Filed: October 16, 2012
    Publication date: April 25, 2013
    Applicant: SONY CORPORATION
    Inventor: SONY CORPORATION
  • Patent number: 8428534
    Abstract: Techniques are disclosed relating to radio frequency (RF) power detection. In one embodiment, a power detection unit is disclosed that includes a multiplier circuit configured to receive a first voltage of a voltage differential signal at gates of a first transistor pair and a second voltage of the voltage differential signal at gates of a second transistor pair. The first multiplier is configured to output a current that varies proportionally to a square of a voltage difference between the first and second voltages. In some embodiments, sources of the first transistor pair are coupled to sources of the second transistor pair, and the sources of the second transistor pair are coupled together. In some embodiments, the power detection unit is configured to compensate for mismatched transistors by applying offset voltages to bodies of transistors in the first and second transistor pairs.
    Type: Grant
    Filed: September 30, 2011
    Date of Patent: April 23, 2013
    Assignee: Silicon Laboratories Inc.
    Inventors: Ravi K. Kummaraguntla, Ruifeng Sun
  • Publication number: 20130088262
    Abstract: Circuits that operate with power supplies of less than 1 Volt are presented. More particularly, circuits that operate with supply voltages near or lower than the threshold voltage of the transistors in those circuits are presented. Various circuits and embodiments such as operational transconductance amplifiers, biasing circuits, integrators, continuous-time sigma delta modulators, track-and-bold circuits, and others are presented. The techniques and circuits can be used in a wide range of applications and various transistors from metal-oxide-semiconductor to bipolar junction transistors may implement the techniques presented herein.
    Type: Application
    Filed: October 2, 2012
    Publication date: April 11, 2013
    Applicant: The Trustees of Columbia University in the City of New York
    Inventor: The Trustees of Columbia University in the City of
  • Patent number: 8405438
    Abstract: In a semiconductor circuit, a high frequency level detecting unit detects a level of a high frequency component adjusted with a first adjusting unit, and a first control unit controls a first gain of the adjusting unit according to the level of the high frequency component thus detected. Further, a low frequency level detecting unit detects a level of a low frequency component adjusted with a second adjusting unit. A second control unit controls a second gain according to the level of the high frequency component and the level of the low frequency component thus adjusted, so that a difference between the level of the high frequency component adjusted with the first adjusting unit and the level of the low frequency component adjusted with the second adjusting unit becomes smaller than a specific level determined in advance.
    Type: Grant
    Filed: July 26, 2011
    Date of Patent: March 26, 2013
    Assignee: Oki Semiconductor Co., Ltd.
    Inventors: Norihiko Satani, Yuichi Matsushita, Takahiro Imayoshi
  • Patent number: 8384441
    Abstract: A semiconductor integrated circuit has a squelch circuit which has a first noninverting input terminal and a first inverting input terminal, which compares differential amplitude between a signal which is input to the first noninverting input terminal and a signal which is input to the first inverting input terminal with a preset threshold, and which outputs a signal depending upon a result of the comparison. The semiconductor integrated circuit has a first switch circuit between a first reception terminal and the first noninverting input terminal. The semiconductor integrated circuit has a second switch circuit between a second reception terminal and the first inverting input terminal. The semiconductor integrated circuit has a third switch circuit between the first reception terminal and the first inverting input terminal. The semiconductor integrated circuit has a fourth switch circuit between the second reception terminal and the first noninverting input terminal.
    Type: Grant
    Filed: January 19, 2011
    Date of Patent: February 26, 2013
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Katsuki Matsudera
  • Patent number: 8381146
    Abstract: A computer-readable, non-transitory medium stores therein a design support program that causes a computer capable of accessing a storage device storing therein for each cell, an output voltage value of the cell, for each elapsed time period from a start of variation of an input voltage applied to the cell, to execute a process. The process includes extracting from the storage device, the output voltage value for each elapsed time period related to an cell under design selected from circuit information of a circuit under design; determining based on a specific voltage value, an extracted elapsed time period to be corrected; adding a time constant of an output from the cell under design to the elapsed time period determined to correction; and outputting the output voltage value for each corrected elapsed time period and the output voltage value for each elapsed time period that is not determined for correction.
    Type: Grant
    Filed: March 16, 2011
    Date of Patent: February 19, 2013
    Assignee: Fujitsu Semiconductor Limited
    Inventor: Mitsuru Onodera
  • Patent number: 8363707
    Abstract: Methods and apparatus are disclosed, such as those involving mixed-mode signaling that includes transmitting a differential signal and a common mode signals over the same pair of interconnect traces. One such apparatus includes a first transmitter configured to transmit a differential signal through a pair of electrically conductive lines in a first direction. The differential signal has a first frequency and carries electronic data. The apparatus further includes a second transmitter configured to transmit a common mode signal through the pair of electrically conductive lines in the first direction. The common mode signal is superimposed onto each of the differential signal. The common mode signal has a second frequency that is lower than the first frequency and carries a control signal. This configuration reduces the number of lines and pins on electronic circuits, thereby saving space thereon.
    Type: Grant
    Filed: March 21, 2008
    Date of Patent: January 29, 2013
    Assignee: Micron Technology, Inc.
    Inventor: Timothy M. Hollis
  • Patent number: 8350598
    Abstract: A multi-stage receiver comprises an input stage, an intermediate stage, and an output stage. The input stage is configured to provide a first signal and a second signal. The intermediate stage is coupled to the input stage and comprises a first amplifying circuit and a second amplifying circuit. Positive and negative input terminals of the first amplifying circuit receive the first signal and the second signal, respectively. Positive and negative input terminals of the second amplifying circuit receive the second signal and the first signal, respectively. The output stage is coupled to the intermediate stage and configured to generate low-skewed differential signals according to output signals of the intermediate stage.
    Type: Grant
    Filed: April 20, 2011
    Date of Patent: January 8, 2013
    Assignee: Nanya Technology Corp.
    Inventor: Yu Meng Chuang
  • Patent number: 8339158
    Abstract: A dynamic high-speed comparative latch comprises a pre-amplifier unit for enlarging input differential signals, a regenerating latch unit for latching outputted differential signals from the pre-amplifier unit by using a positive feedback, specifically, converting the output of the pre-amplifier unit into a latched result at a first state of a clock cycle, and then retaining the latched result and simultaneously resetting relevant nodes at a second state opposite to the first state of the clock cycle, and a latch unit for outputting the effective outputted value of the regenerating latch unit when the regenerating latch unit being in a retaining state. The pre-amplifier unit is connected with the regenerating latch unit, and the regenerating latch unit is connected with the latch unit. The pre-amplifier unit comprises only one input clock signal. The present invention has a simple structure, and ensures the correctness of the output result of the latch.
    Type: Grant
    Filed: December 30, 2010
    Date of Patent: December 25, 2012
    Assignee: IPGoal Microelectronics (SiChuan) Co., Ltd.
    Inventors: Bin Li, Guosheng Wu
  • Patent number: 8330501
    Abstract: A system for voltage buffering within an integrated circuit (IC). The system can include a first buffer having an input and an output. The first buffer can be configured to buffer a received maximum input voltage approximately equal to a positive voltage supply powering the system. The system can include a second buffer having an input and an output. The input of the first buffer can be coupled to the input of the second buffer. The output of the first buffer can be coupled to the output of the second buffer. The second buffer can be configured to buffer a received minimum input voltage approximately equal to a negative voltage supply powering the system. The system further can include a controller configured to selectively enable only the first buffer or the second buffer at any given time.
    Type: Grant
    Filed: October 19, 2010
    Date of Patent: December 11, 2012
    Assignee: Xilinx, Inc.
    Inventors: Vikram Santurkar, Gautham S. Jami
  • Patent number: 8330499
    Abstract: In a comparator circuit having a differential amplifier, which makes a logical judgment by comparing an input voltage with a reference voltage, generates and outputs a resulting output voltage thereof, a current source generates and supplies a bias current of a predetermined minute current to the differential amplifier, and a first inverter circuit inverts a differential voltage from the differential amplifier. An adaptive bias current generator circuit detects the bias current of the current source, and a through current of the first inverter circuit. The adaptive bias current generator circuit generates and supplies an adaptive bias current for executing adaptive bias current control to the differential amplifier to allow the differential amplifier to operate with the bias current upon no logical judgment, and to allow the differential amplifier to operate by using the adaptive bias current obtained by increasing the bias current upon logical judgment.
    Type: Grant
    Filed: February 28, 2011
    Date of Patent: December 11, 2012
    Assignee: Semiconductor Technology Academic Research Center
    Inventors: Tetsuya Hirose, Keishi Tsubaki, Masahiro Numa
  • Patent number: 8330500
    Abstract: A comparator comprises a current mirror, a differential input pair, and a auxiliary circuit. The current mirror has a biasing end coupled to a power voltage, a first end, and a current outputting end coupled to an output node of the comparator. The differential input pair has a first and second input ends for respectively receiving a first voltage and a second voltage, a second and third ends, and a ground end, wherein the third end is coupled to the first end. The auxiliary circuit is coupled between the output node and the second end, and provides a minimum voltage of a comparison result output at the output node. The comparison result is the power voltage when the first voltage is larger than the second voltage, and the comparison result is the minimum voltage when the first voltage is less than the second voltage.
    Type: Grant
    Filed: November 25, 2010
    Date of Patent: December 11, 2012
    Assignee: Elite Semiconductor Memory Technology Inc.
    Inventor: Yi-Heng Liu
  • Publication number: 20120299623
    Abstract: In one form, a power converter for a power detector or the like includes first and third transistors of a first conductivity type, and second and fourth transistors of a second conductivity type. A control electrode of the first transistor receives a first bias voltage plus a positive component of a differential input signal. The second transistor is coupled in series with the first transistor and has a control electrode receiving a second bias voltage plus a negative component of the differential input signal. The third transistor is biased using the first bias voltage plus the negative component. The fourth transistor is coupled in series with the third transistor and is biased using the second bias voltage plus the positive component. A common interconnection point of the first and third transistors forms an output node.
    Type: Application
    Filed: August 13, 2012
    Publication date: November 29, 2012
    Inventors: Ruifeng Sun, Yunteng Huang
  • Patent number: 8319526
    Abstract: A latched comparator circuit comprises an input amplification unit, a buffer unit, and a control unit. The input amplification unit comprises a first and a second input terminal for receiving a first and a second input voltage, respectively, of the latched comparator circuit. The input amplification unit further comprises a first and a second output terminal for outputting a first and a second output voltage, respectively, of the input amplification unit. In addition, the input amplification unit comprises a reset terminal arranged to receive a reset signal for resetting the input amplification unit. The buffer unit is operatively connected to the first and the second output terminal of the input amplification unit. Furthermore, the buffer unit comprises a first and a second output terminal for outputting a first and a second output voltage, respectively, of the buffer unit. The control unit is operatively connected to the input amplification unit and the buffer unit.
    Type: Grant
    Filed: November 17, 2009
    Date of Patent: November 27, 2012
    Assignee: CSR Technology Inc.
    Inventor: Christer Jansson
  • Patent number: 8310278
    Abstract: A voltage detection circuit includes operational amplifiers, a battery, and a voltage circuit. The voltage circuit offsets the inverting input terminals and non-inverting input terminals of the operational amplifiers to the positive side with reference to a ground GND.
    Type: Grant
    Filed: December 23, 2010
    Date of Patent: November 13, 2012
    Assignees: Denso Corporation, Toyota Jidosha Kabushika Kaisha
    Inventors: Yusuke Shindo, Tsuneo Maebara, Keisuke Hata
  • Patent number: 8310279
    Abstract: Techniques for providing a comparator incorporating amplitude hysteresis. In an exemplary embodiment, a current offset stage is coupled to a comparator having a folded cascode architecture. The current offset stage offsets the current generated from an input stage to delay switching of the comparator output to implement amplitude hysteresis. In an exemplary embodiment, rail-to-rail input voltages may be accommodated by providing dual NMOS and PMOS input stages. In another exemplary embodiment, the amplitude hysteresis may be controlled by an adjustable threshold voltage. In yet another exemplary embodiment, a constant transconductance gm bias circuit may be provided to maintain the stability of the threshold voltage across input common-mode voltage and/or other variations.
    Type: Grant
    Filed: May 18, 2009
    Date of Patent: November 13, 2012
    Assignee: QUALCOMM, Incorporated
    Inventor: Douglas Sudjian
  • Publication number: 20120280719
    Abstract: An apparatus and a method are provided for selectively enabling and disabling a squelch circuit in a Serial Advanced Technology Attachment (SATA) host or SATA device while maintaining proper operation of the host and device. An apparatus and method are provided which allow the squelch circuit to be selectively enabled and disabled across SATA power states (PHY Ready, Partial, and Slumber) and in Advanced Host Controller Interface (AHCI) Listen mode.
    Type: Application
    Filed: March 19, 2012
    Publication date: November 8, 2012
    Inventors: Jien-Hau Ng, Tea M. Lee
  • Publication number: 20120274359
    Abstract: A high-speed differential comparator circuit is provided with an accurately adjustable threshold voltage. Differential reference voltage signals are provided to control the threshold voltage of the comparator. The common mode voltage of the reference signals preferably tracks the common mode voltage of the differential high-speed serial data signal being processed by the comparator circuit.
    Type: Application
    Filed: July 2, 2012
    Publication date: November 1, 2012
    Applicant: Altera Corporation
    Inventors: Weiqi Ding, Mingde Pan
  • Patent number: 8289054
    Abstract: A high voltage differential pair and op amp implemented in a low voltage semiconductor process. The high voltage differential pair expands the incoming common mode voltage of a differential pair to multiple times the normal operating voltage of the differential pair through the use of high voltage current sources, current sinks and stacks of transistors. The high voltage op amp includes a high voltage input stage and a high voltage common source amplifier to expand the output voltage range to multiple times the normal operating voltage of the op amp.
    Type: Grant
    Filed: September 13, 2010
    Date of Patent: October 16, 2012
    Assignee: Alfred E. Mann Foundation For Scientific Research
    Inventor: Edward K. F. Lee
  • Patent number: 8289053
    Abstract: An inverter is configured by double gate TFTs, and an inverter is configured by double gate TFTs. Top gate terminals of the TFTs that configure the inverter are connected to an input terminal DAT(+), and bottom gate terminals are connected to an output of the inverter and an output terminal OUT. Bottom gate terminals of the TFTs that configure the inverter are connected to an input terminal DAT(?), and bottom gate terminals are connected to an output of the inverter. With this, threshold voltages of the inverters are controlled so as to facilitate switching operations of the inverters, and whereby the comparator circuit operates at a high speed. It is possible to obtain a comparator circuit that is insusceptible to a variation in the threshold voltages of the transistors and fluctuation of a common mode voltage of an input signal and capable of operating at a high speed.
    Type: Grant
    Filed: March 17, 2009
    Date of Patent: October 16, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yasuyuki Ogawa, Christopher Brown
  • Patent number: 8275026
    Abstract: An adjustable equalizer that includes a first branch including a low pass filter (LPF) and having a variable gain (?), and a second branch including a high pass filter (HPF) and having another variable gain (?). The equalizer can be implemented using CMOS technology so that the gain parameters ? and ? are independently adjustable and the equalizer is capable of equalizing an input indicative of data having a maximum data rate of at least 1 Gb/s. In some embodiments, the equalizer includes two differential pairs of MOS transistors and a controllable current source determines the tail current for each differential pair. When the equalizer includes purely resistive impedances Z0 and Z1, the equalizer's transfer function is Z1/Z0·(?+?·(1+s·C0·Z0)), where ? is a gain parameter determined by the tail current of one differential pair and ? is a gain parameter determined by the tail current of the other differential pair.
    Type: Grant
    Filed: April 27, 2007
    Date of Patent: September 25, 2012
    Assignee: Silicon Image, Inc.
    Inventor: Dongyun Lee
  • Patent number: 8269527
    Abstract: A hysteresis comparator circuit that compares first and second input signals to output a hysteresis output signal includes a constant current source, a first comparator, a second comparator, and an output circuit. The constant current source includes a load resistor to generate a given constant current. The first comparator is controlled by the constant current supplied from the constant current source to compare the first and second input signals to output a first comparison result. The second comparator is controlled by the constant current supplied from the constant current source to compare the first and second input signals to output a second comparison result. The output circuit has a pair of inputs thereof connected to the first and second comparators, respectively, which inverts an output thereof in response to each of the first and second comparison results to generate the hysteresis output signal.
    Type: Grant
    Filed: September 2, 2010
    Date of Patent: September 18, 2012
    Assignee: Ricoh Company, Ltd.
    Inventor: Yasuo Ueda
  • Patent number: 8258816
    Abstract: An integrated circuit comparator comprises a differential amplifier, a source follower circuit coupled to a gate terminal of a first transistor in the differential amplifier, and an output circuit. One or more source follower circuits may be utilized in connection with the differential amplifier, and one or more source follower circuits may be utilized in connection with the output circuit.
    Type: Grant
    Filed: October 20, 2010
    Date of Patent: September 4, 2012
    Assignee: Micron Technology, Inc.
    Inventor: Leonard Forbes
  • Patent number: 8253444
    Abstract: A receiving circuit includes an impedance compensating circuit, a first input terminal and a second input terminal coupled to a first signal line and a second signal line, a first signal and a second signal corresponding to differential signals being transmitted at the first input terminal and the second input terminal, respectively, a signal input circuit, coupled to the first input terminal and the second input terminal, which receives the first signal and the second signal are input, and a differential-signal detector that detects whether or not the differential signals are supplied to the first input terminal and the second input terminal.
    Type: Grant
    Filed: January 29, 2010
    Date of Patent: August 28, 2012
    Assignee: Fujitsu Semiconductor Limited
    Inventors: Tetsuya Hayashi, Daisuke Suzuki
  • Patent number: 8248107
    Abstract: A high-speed differential comparator circuit is provided with an accurately adjustable threshold voltage. Differential reference voltage signals are provided to control the threshold voltage of the comparator. The common mode voltage of the reference signals preferably tracks the common mode voltage of the differential high-speed serial data signal being processed by the comparator circuit.
    Type: Grant
    Filed: March 11, 2010
    Date of Patent: August 21, 2012
    Assignee: Altera Corporation
    Inventors: Weiqi Ding, Mingde Pan
  • Patent number: 8248108
    Abstract: A comparator formed by first and second stages. The second stage is formed by a pair of output transistors connected between a power-supply line and respective output nodes; a pair of bias transistors, connected between a respective output node and a current source; a pair of memory elements, connected between the control terminals of the output transistors and opposite output nodes; and switches coupled between the control terminals of the respective output transistors and the respective output nodes. In an initial autozeroing step, the first stage stores its offset so as to generate an offset-free current signal. In a subsequent tracking step, the second stage receives the current signal and the memory elements store control voltages of the respective output transistors. In a subsequent evaluating step, the first stage is disconnected from the second stage and the memory elements receive the current signal and switch the first and the second output node depending on the current signal.
    Type: Grant
    Filed: March 18, 2010
    Date of Patent: August 21, 2012
    Assignee: STMicroelectronics S.r.l.
    Inventors: Manuel Santoro, Fabio Bottinelli
  • Patent number: 8228095
    Abstract: According to an exemplary aspect of the present invention, it is possible to provide a communication device that can prevent misdetection of a disconnection and achieve a high output level on a receptacle side. In the communication device, a reference voltage generating circuit outputs a reference voltage that changes according to a first control signal. A differential amplifier circuit amplifies input signals and outputs differential output signals, the voltages of which change according to a second control signal, to a receptacle. A disconnection detector circuit outputs a disconnection detecting signal when a differential amplitude voltage between the differential output signals is equal to or higher than the reference voltage. The reference voltage generating circuit outputs the reference voltage that is larger than the differential amplitude voltage when the receptacle is terminated and that is smaller than the differential amplitude voltage when the receptacle is opened.
    Type: Grant
    Filed: December 20, 2010
    Date of Patent: July 24, 2012
    Assignee: Renesas Electronics Corporation
    Inventor: Takahiro Inoue
  • Patent number: 8228094
    Abstract: This disclosure relates to permuting transistors to compensate for offsets generated by transient variations of the transistors' parameters.
    Type: Grant
    Filed: August 11, 2009
    Date of Patent: July 24, 2012
    Assignee: Infineon Technologies AG
    Inventor: Franz Kuttner
  • Patent number: 8212589
    Abstract: A signal transfer circuit according to the present invention includes a differential signal generation unit that generates a differential signal according to a voltage difference between two input signals, a voltage difference detection unit that detects a voltage difference between the two input signals input to the differential signal generation unit, and a signal output unit that outputs a signal including a predetermined value if the voltage difference is not detected by the voltage difference detection unit, and outputs the differential signal generated by the differential signal generation unit if the voltage difference is detected by the voltage detection unit.
    Type: Grant
    Filed: May 19, 2010
    Date of Patent: July 3, 2012
    Assignee: Renesas Electronics Corporation
    Inventors: Akihiro Hiramatsu, Yutaka Saeki
  • Patent number: 8207782
    Abstract: A circuit to minimize thermally generated offset voltages includes a differential pair of transistors having a first transistor and a second transistor and coupled to a current source, a differential input having a first input coupled to the first transistor and having a second input coupled to the second transistor, a pair of bypass transistors having a first bypass transistor and a second bypass transistor, the first bypass transistor coupled in parallel with the first transistor and the second bypass transistor coupled in parallel with the second transistor, wherein the pair of bypass transistors is coupled to the current source, and control circuitry coupled to the pair of bypass transistors for controlling current through the pair of bypass transistors.
    Type: Grant
    Filed: March 1, 2011
    Date of Patent: June 26, 2012
    Assignee: HRL Laboratories, LLC
    Inventor: Albert E. Cosand
  • Patent number: 8198921
    Abstract: A dynamic comparator with background offset calibration is provided. The dynamic comparator includes at least one input differential pair, a first back-to-back inverter, a second back-to-back inverter, and an integrator. The input differential pair includes two current branches, wherein one of the current branches has an input referred offset. The first back-to-back inverter determines which one of the two current branches has the input referred offset in response to a first clock signal and generates two control signals accordingly. The integrator generates two calibration voltages for the input differential pair in response to the two control signals, so as to calibrate the input referred offset. The second back-to-back inverter determines a difference between two input signals received by the input differential pair after the input referred offset is calibrated in response to a second clock signal and outputs two comparison signals accordingly.
    Type: Grant
    Filed: December 17, 2009
    Date of Patent: June 12, 2012
    Assignee: Industrial Technology Research Institute
    Inventors: Bo-Wei Chen, Tim-Kuei Shia, Ji-Eun Jang
  • Patent number: 8198920
    Abstract: A low current comparator with programmable hysteresis is disclosed that uses a ratio of latch intrinsic (internal) latch capacitance and capacitance of a sample capacitor to adjust hysteresis. In some implementations, the comparator includes a switch capacitor sampling stage coupled to a dynamic latch output stage. Depending on an output state (0 or 1) of the comparator, hysteresis is generated by adding or subtracting a first charge stored in the latch intrinsic capacitance to or from a second charge stored in the sampling capacitor. The ratio of latch intrinsic capacitance and the capacitance of the sampling capacitor can be adjusted to trim hysteresis value. The hysteresis function does not require additional capacitors or additional logic.
    Type: Grant
    Filed: March 23, 2009
    Date of Patent: June 12, 2012
    Assignee: Atmel Corporation
    Inventor: Joel Chatal
  • Publication number: 20120126855
    Abstract: This document discusses, among other things, apparatus and methods for controlling a hysteresis range of a voltage comparator. In an example, an apparatus can include an amplifier having a temperature dependency, a comparator configured to receive first and second currents and to provide an output voltage indicative of a hysteretic comparison of the first and second input voltages, wherein a range of hysteresis of the apparatus is controlled over a range of temperatures. In an example, the amplifier can be configured to receive first and second input voltages and to provide the first and second currents.
    Type: Application
    Filed: November 22, 2011
    Publication date: May 24, 2012
    Inventors: Tyler Daigle, Andrew M. Jordan
  • Publication number: 20120119790
    Abstract: A comparison system including a dynamic comparator, a background offset calibration circuit, and an asynchronous reset timing control circuit is presented. The background offset calibration circuit is coupled to the dynamic comparator, and generates calibration signals in response to reference switching control signals. Where calibration signals are used to calibrate the input refer offset of the dynamic comparator. The asynchronous reset timing control circuit is coupled to the dynamic comparator and the background offset calibration circuit, and generates a control clock signal and the reference switching control signals in response to the output signals of the dynamic comparator and a plurality of basic clock signals. During each clock cycle of the first basic clock signal, the control clock signal is used to control the dynamic comparator to perform two data comparison, one for the input refer offset and the other for a differential input signal.
    Type: Application
    Filed: December 30, 2010
    Publication date: May 17, 2012
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventor: Bo-Wei Chen
  • Publication number: 20120112794
    Abstract: A calibration circuit for calibrating a differential driver with a differential output port including a first output node and a second output node includes: a comparing circuit arranged to receive a first output voltage corresponding to the first output node and a second output voltage corresponding to the second output node, and generate a comparison result according to the first output voltage, the second output voltage, and a predetermined voltage; and a controlling circuit coupled to the comparing circuit, a first resistive element and a second resistive element. The controlling circuit is arranged to adjust the first resistive element and the second resistive element according to the comparison result, wherein the first resistive element is coupled between the first output node and a reference voltage, and the second resistive element is coupled between the second output node and the reference voltage.
    Type: Application
    Filed: November 4, 2010
    Publication date: May 10, 2012
    Inventors: Kuan-Hua Chao, Yan-Bin Luo, Tse-Hsiang Hsu
  • Patent number: 8174291
    Abstract: An improved buffer circuit and method for minimizing (or altogether eliminating) duty cycle distortion between input and output signals of the buffer circuit are provided herein. In general, the improved buffer circuit essentially decouples the charging and discharging current paths of the buffer circuit from a reference voltage supplied to the buffer circuit. This ensures substantially equal time delays between rising and falling edges of the input and output signals, thereby decreasing duty cycle distortion and maintaining a maximum operating frequency of the buffer circuit, even when the reference voltage approaches a transistor threshold voltage. In addition, the improved method may include forwarding an input signal with an input duty cycle onto mutually connected gate terminals of a pair of pull-down transistors, and activating/inactivating at least one of the pair of pull-down transistors during logic high and logic low voltage values of the input duty cycle, respectively.
    Type: Grant
    Filed: June 24, 2004
    Date of Patent: May 8, 2012
    Assignee: Cypress Semiconductor Corporation
    Inventors: Pulkit Shah, Gajendar Rohilla
  • Patent number: 8174292
    Abstract: A current sensing circuit for a pulse width modulation (PWM) application may include first and second input terminals to be coupled to ends of a sensing resistance, an output terminal, and first and second internal circuit nodes. The current sensing circuit further may include an input block comprising a first transconductance amplifier to be coupled to a supply voltage. The first transconductance amplifier may be coupled to the first and second input terminals and to the first and second internal circuit nodes. The current sensing circuit may also include an amplifier block comprising an amplifier to be coupled to a reference voltage, and coupled to the first and second internal circuit nodes and the output terminal, and a feedback block comprising a second transconductance amplifier to be coupled to the supply voltage and being coupled to the output terminal and the first and second internal circuit nodes.
    Type: Grant
    Filed: August 14, 2009
    Date of Patent: May 8, 2012
    Assignee: STMicroelectronics, S.R.L.
    Inventors: Maurizio Nessi, Luca Schillaci
  • Patent number: 8169237
    Abstract: In one embodiment, a circuit such as a comparator circuit includes a differential stage adapted to receive a differential input signal and first and second diodes coupled to the differential stage. The first and second diodes are adapted to selectively switch on and off to provide a differential output signal at first and second differential output nodes in response to the differential input signal. The circuit may include an output stage coupled to the first and second diodes at the first and second differential output nodes, with the output stage adapted to convert the differential output signal to a single ended output signal. The circuit may also include a current source adapted to selectively provide a reference current to the first or second diode in an off state to reduce voltage swing of the first or second diode between the off and an on state.
    Type: Grant
    Filed: October 17, 2011
    Date of Patent: May 1, 2012
    Assignee: Lattice Semiconductor Corporation
    Inventor: Ravindar Mohan Lall
  • Patent number: 8171353
    Abstract: Systems, controllers and methods are disclosed, such as an initialization system including a controller that receives patterns of read data coupled from a memory device through a plurality of read data lanes. The controller is operable to detect any lane-to-lane skew in the patterns of read data received through the read data lanes. The controller then adjusts the manner in which the read data received through the read data lanes during normal operation are divided into frames. The controller can also couple patterns of command/address bits to the memory device through a plurality of command/address lanes. The memory device can send the received command/address bits back to the controller through the read data lanes. The controller is operable to detect any lane-to-lane skew in the patterns of command/address bits received through the read data lanes to adjust the manner in which the command/address bits coupled through the command/address lanes during normal operation are divided into frames.
    Type: Grant
    Filed: February 8, 2011
    Date of Patent: May 1, 2012
    Assignee: Micron Technology, Inc.
    Inventor: A. Kent Porterfield
  • Publication number: 20120098572
    Abstract: Traditionally, latched comparators have suffered from performance problems related to exposure of the latch to load capacitances. Even attempts to isolate the latch from the load capacitances by way of resistors has resulted in performance problems (namely, voltage swing degradation). Here, however, a latched comparator is provided that employs inductors to generally provide isolation from load capacitances, which generally improves performance. Moreover, the latch has been modified to accommodate the inductors during a track period (namely, provision of grounding paths).
    Type: Application
    Filed: October 25, 2010
    Publication date: April 26, 2012
    Applicant: Texas Instruments Incorporated
    Inventors: Vaibhav Tripathi, Marco Corsi, Venkatesh Srinivasan
  • Patent number: 8164364
    Abstract: A differential input circuit (1-1) includes first (Q0) and second (Q1) input transistors having control electrodes coupled to first (Vin+) and second (Vin?) input signals, respectively. A pass transistor (P3) is coupled between first electrodes of the first and second input transistors. First (N1) and second (N2) level shift transistors have control electrodes coupled to the first and second input signals, respectively. A voltage selector circuit (22) selects a voltage on a first electrode of one of the first and second level shift transistors according to which is at a higher voltage, and produces a corresponding control voltage (V19) on a control electrode of the pass transistor so as to limit a voltage difference between the first electrode and the control electrode of the first input transistor (Q0) when it is turned off in response to a large difference between the first and second input signals.
    Type: Grant
    Filed: July 27, 2010
    Date of Patent: April 24, 2012
    Assignee: Texas Instruments Incorporated
    Inventors: Jerry L. Doorenbos, Sudarshan Udayashankar