Bus Or Line Termination (e.g., Clamping, Impedance Matching, Etc.) Patents (Class 326/30)
  • Patent number: 8415971
    Abstract: A transceiving circuit resistance calibrating method, which is applied to a transceiving circuit. The method includes: inputting a first current to a transmitter to generate a first output voltage, wherein the first current is generated according to a ratio between a predetermined voltage and an inner resistor of a chip; inputting a second current to a transmitter to generate a second output voltage, wherein the first current is generated according to a ratio between the predetermined voltage and a predetermined resistor; and adjusting a first adjustable resistance module according to a difference between the first output voltage and the second output voltage.
    Type: Grant
    Filed: February 15, 2012
    Date of Patent: April 9, 2013
    Assignee: Realtek Semiconductor Corp.
    Inventors: Chien-Ming Wu, Su-Liang Liao
  • Patent number: 8415986
    Abstract: A voltage-mode driver circuit supporting pre-emphasis includes multiple resistors, and multiple transistors operated as switches. Control signals operating the transistors represent a logic level of an input signal to the driver circuit. To generate a pre-emphasized output, the transistors are operated to connect a parallel arrangement of the resistors between output terminals of the driver and corresponding constant reference potentials. To generate an output in the steady-state, the transistors are operated to connect some of the resistors across the output terminals of the driver, thereby reducing the output voltage. A desired output impedance of the driver, and a desired level of pre-emphasis are obtained by appropriate selection of the resistance values of the resistors. The current consumption of the driver is less in the steady-state than in the pre-emphasis mode.
    Type: Grant
    Filed: December 28, 2010
    Date of Patent: April 9, 2013
    Assignee: Texas Instruments Incorporated
    Inventors: Sumantra Seth, Rajavelu Thinakaran
  • Patent number: 8416106
    Abstract: In one embodiment, a comparator of a Flash analog-to-digital converter (ADC) is calibrated in the background by switching the comparator to a feedback loop, determining the comparator's current reference level, and adjusting the comparator's reference level to a target reference level by charging a reference capacitor coupled the comparator.
    Type: Grant
    Filed: April 20, 2011
    Date of Patent: April 9, 2013
    Assignee: Fujitsu Limited
    Inventor: Pradip Thachile
  • Patent number: 8410813
    Abstract: A method and apparatus for A Low Power AC On-Die-Termination (ODT) Circuit using active components reduces receiver power consumption.
    Type: Grant
    Filed: May 24, 2011
    Date of Patent: April 2, 2013
    Assignee: Integrated Device Technology, Inc.
    Inventors: Liang Leon Zhang, Suresh Atluri, Yue Yu, Al Xuefeng Fang
  • Patent number: 8410812
    Abstract: A “supply-less” transmitter output stage is provided for a transmitter. This transmitter output stage can include a tunable source termination and a reference voltage generator. The tunable source termination can be coupled between a differential pair of the transmitter. The reference voltage generator can advantageously generate reference voltages from a far-end termination. These reference voltages provide a way of translating the internal supply voltage level to the pad voltage level to enable/disable the tunable source termination. Also, it provides a way to minimize leakage and minimize the junction stress of switching transistors in the tunable source termination as well as the transmitter. The dependency between the reference voltages and the far-end termination voltage makes this design more portable to other supply voltages and other technologies specifications other than HDMI.
    Type: Grant
    Filed: October 22, 2009
    Date of Patent: April 2, 2013
    Assignee: Synopsys, Inc.
    Inventors: Nelson Lam, Dino A. Toffolon
  • Patent number: 8410814
    Abstract: Receiver circuits for differential and single-ended signals are disclosed. In some embodiments, a receiver may include a first amplifier configured to receive a first signal of a differential pair of signals at a first input and a second signal of the differential pair of signals at a second input when operating in differential mode. The receiver may also include a second amplifier coupled to the first amplifier, where the second amplifier is configured to receive a reference signal at a third input and a single-ended signal at the first input when operating in single-ended mode. In some embodiments, several receivers may be used, for example, to process a differential clock signal and one or more single-ended data signals referenced to the clock signal and/or differential data signals referenced to a single-ended clock signal. In some embodiments, the delays of each signal propagating through each respective receiver may be independently adjusted.
    Type: Grant
    Filed: June 16, 2011
    Date of Patent: April 2, 2013
    Assignee: Apple Inc.
    Inventors: Gregory S. Scott, Vincent R. von Kaenel
  • Publication number: 20130069689
    Abstract: According to example embodiments, a method for operating a memory device includes receiving an on-die termination (ODT) signal through an ODT pin, and issuing a command or controlling an ODT circuit according to the ODT signal.
    Type: Application
    Filed: September 14, 2012
    Publication date: March 21, 2013
    Applicant: SAMSUNG ELECTRONICS CO., LTD.
    Inventors: In Dal SONG, Jung Hwan CHOI, Yun Seok YANG
  • Patent number: 8395412
    Abstract: A method includes issuing a calibration command and performing a calibration operation in response to the calibration command. The calibration operation includes adjusting an impedance of a first replica buffer with updating a first code, the first replica buffer being substantially identical in circuit configuration to one of pull-up and pull-down circuits included in an output buffer, adjusting impedance of a second replica buffer with updating a second code, the second replica buffer being substantially identical in circuit configuration to the other of the pull-up and pull-down circuits included in the output buffer, controlling a first latch circuit to hold the first code when the impedance of the first replica buffer reaches a first level, and controlling a second latch circuit to hold the second code when the impedance of the second replica buffer reaches a second level.
    Type: Grant
    Filed: June 16, 2011
    Date of Patent: March 12, 2013
    Assignee: Elpida Memory, Inc.
    Inventors: Fumiyuki Osanai, Hiroki Fujisawa
  • Patent number: 8395411
    Abstract: A constant impedance driver provides controlled output slew rates. The driver includes a plurality of buffers, each with an output impedance that is multiple of the output impedance of the driver. Outputs of buffers are coupled in parallel to form the output of the driver. Inputs to the buffers are coupled to an input signal or delayed versions of the input signal. The buffer inputs may be selectively coupled to taps of a delay line to provide selected slew rates on the output of the driver. The buffers may be selectively enabled to change or calibrate the output impedance of the driver.
    Type: Grant
    Filed: October 8, 2010
    Date of Patent: March 12, 2013
    Assignee: QUALCOMM Incorporated
    Inventor: Jan C. Diffenderfer
  • Patent number: 8390316
    Abstract: An example embodiment of the present invention relates to a method and corresponding apparatus that terminates circuit connectivity in a bus by determining location of an instrument on the bus, and based on coupling a terminating resistance to the instrument. The example embodiment may couple a terminating resistance with the instrument placed at the end of a bus by employing at least one male-to-male connector arranged to establish a connection between the female receptacles of the terminating resistance and the bus. In order to determine a state of termination of circuit connectivity in a bus, an example embodiment of the present invention may connect a transceiver to a terminating resistance and determine a state of termination of circuit connectivity in the bus as a function of sensing receive activity in the transceiver.
    Type: Grant
    Filed: September 9, 2008
    Date of Patent: March 5, 2013
    Assignees: Airmar Technology Corporation, Furuno Electric Company Limited
    Inventors: Frederic S. Boericke, II, Danny J. Fladung, Stephen G. Boucher, Eric Kunz
  • Patent number: 8390317
    Abstract: An integrated circuit (IC) device, system and related method of communicating data are described. The IC device includes; a data port configured to provide output data to a channel and receive input data from the channel, an impedance matching circuit connected to the data port and configured to operate as an output driver circuit when the output data is being transmitted and as an on die termination circuit when the input data is being received, and an active inductive bias circuit connected to the data port in parallel with the impedance matching circuit, and configured to adjust the impedance of the data port to the channel during transmission of the output data as a function of output data frequency and adjust the impedance of the data port to the channel during receipt of the input data as a function of input data frequency.
    Type: Grant
    Filed: July 8, 2010
    Date of Patent: March 5, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Seung-jun Bae, Young-sik Kim, Sang-hyup Kwak
  • Patent number: 8390315
    Abstract: Circuits and techniques for operating an integrated circuit (IC) with a configurable input-output circuit are disclosed. A disclosed circuit includes a single-ended input-output buffer coupled to an output terminal. The single-ended input-output buffer is operable to transmit an input signal to the output terminal as an output signal. A pre-emphasis circuit that is operable to sharpen a first edge and a second edge of the output signal is coupled between the single-ended input-output buffer and the output terminal. The first edge of the output signal is sharpened when the input signal switches from a first logic level to a second logic level while the second edge of the output signal is sharpened when the input signal switches from the second logic level to the first logic level.
    Type: Grant
    Filed: January 20, 2012
    Date of Patent: March 5, 2013
    Assignee: Altera Corporation
    Inventors: Xiaobao Wang, Chiakang Sung, Joseph Huang, Khai Nguyen
  • Patent number: 8390318
    Abstract: Disclosed herein is a device that includes a replica buffer circuit that drives a calibration terminal, a reference-potential generating circuit that generates a reference potential, a comparison circuit that compares a potential appearing at the calibration terminal with the reference potential, and a control circuit that changes an output impedance of the replica buffer circuit based on a result of a comparison by the comparison circuit. The reference-potential generating circuit includes a first potential generating unit activated in response to an enable signal and a second potential generating unit activated regardless of the enable signal, and an output node of the first potential generating unit and an output node of the second potential generating unit are commonly connected to the comparison circuit.
    Type: Grant
    Filed: February 21, 2012
    Date of Patent: March 5, 2013
    Assignee: Elpida Memory, Inc.
    Inventors: Hideyuki Yokou, Takanori Eguchi, Manabu Ishimatsu
  • Publication number: 20130049798
    Abstract: An exemplary motherboard includes a controller, and two different network card connectors. At least one of the two network card connectors is electronically connected to the controller via a resistor. A user of the motherboard may choose to use either the first network card connector, or the second network card connector, or the first network card connector and the second network card connector simultaneously.
    Type: Application
    Filed: November 20, 2011
    Publication date: February 28, 2013
    Applicant: HON HAI PRECISION INDUSTRY CO., LTD.
    Inventors: PEI-YI CHANG, CHENG-CHUAH LIN
  • Publication number: 20130049797
    Abstract: An embodiment of an impedance calibration circuit and method, a device including an impedance calibration circuit, and a transmission link system.
    Type: Application
    Filed: August 25, 2011
    Publication date: February 28, 2013
    Applicant: STMicronelectronics Pvt. Ltd.
    Inventors: Mayank Kumar SINGH, Daljeet KUMAR, Hiten ADVANI
  • Publication number: 20130049799
    Abstract: A calibration circuit includes an amplifier, a current steering digital-to-analog converter (DAC), a comparator, a slew calibration network, and an on-die termination (ODT) network. The amplifier generally has a first input, a second input, and an output. The first input generally receives a reference signal. The current steering digital-to-analog converter (DAC) generally has a first input coupled to the output of the amplifier, a first output coupled to the second input of the amplifier, and a second output coupled to a circuit node. The comparator generally has a first input receiving the reference signal, a second input coupled to the circuit node, and an output at which an output of the calibration circuit may be presented. The slew calibration network is generally coupled to the circuit node and configured to adjust a slew rate of the calibration circuit. The on-die termination (ODT) network is generally coupled to the circuit node.
    Type: Application
    Filed: October 30, 2012
    Publication date: February 28, 2013
    Applicant: LSI CORPORATION
    Inventor: LSI Corporation
  • Patent number: 8384423
    Abstract: A memory controller includes a transmit circuit coupled to an output node and a receive circuit coupled to an input node. The transmit circuit transmits first data to a memory device through the output node and the receive circuit is configured to receive second data from the memory device through the input node. The memory controller includes a calibration circuit and control logic coupled to the calibration circuit, where the calibration circuit and the control logic are configured to select a first reference voltage and a driver impedance for the transmit circuit and are configured to select a second reference voltage and a termination impedance for the receive circuit. The first reference voltage, the second reference voltage, the driver impedance and the termination impedance are selected from a set of pre-determined values, which are associated with different signaling modes for communication of the first data and the second data.
    Type: Grant
    Filed: May 20, 2008
    Date of Patent: February 26, 2013
    Assignee: Rambus Inc.
    Inventors: Huy M. Nguyen, Vijay Gadde, Bret G. Stott
  • Patent number: 8384422
    Abstract: One aspect of the invention is a terminal resistance device including a variable terminal resistance unit including a plurality of first terminal resistance elements connectable to a transmission path and a terminal resistance control unit that transmits a first control signal of a thermometer code to the variable terminal resistance unit. The first terminal resistance elements have the same resistance value and the first control signal is a signal for selecting the first terminal resistance elements to be connected to the transmission path.
    Type: Grant
    Filed: November 27, 2009
    Date of Patent: February 26, 2013
    Assignee: Renesas Electronics Corporation
    Inventors: Yuuji Matsui, Noriaki Suyama
  • Patent number: 8384424
    Abstract: An averaged impedance calibration is obtained by utilizing two separately controlled resistive loads arranged in parallel and choosing two adjacent control codes to configure switch arrays to set the resistance of each of the separate resistive loads. The resistance of the resistive loads is averaged to provide greater accuracy. The two adjacent control codes are close to the target impedance value and typically one is slightly higher and one is slightly lower than the target impedance value.
    Type: Grant
    Filed: April 8, 2011
    Date of Patent: February 26, 2013
    Assignee: ATI Technologies ULC
    Inventor: Junho J. H. Cho
  • Publication number: 20130043901
    Abstract: An on-die termination circuit includes a reference period signal generation circuit that generates a reference period signal according to a level of a reference voltage, a first period signal generation circuit that generates a first period signal according to a voltage level of a pad, a period comparison circuit that compares a period of the first period signal with a period of the reference period signal and count a plurality of driving signals, and a driver circuit that drives the pad in response to the plurality of driving signals.
    Type: Application
    Filed: October 22, 2012
    Publication date: February 21, 2013
    Applicant: SK hynix Inc.
    Inventors: Yong Ju KIM, Hyung Soo KIM, Hae Rang CHOI, Jae Min JANG
  • Publication number: 20130043900
    Abstract: Apparatuses and methods for driving input data signals onto signal lines as output data signals are disclosed. An example apparatus includes a detection circuit, a driver adjust circuit, and a data driver. The detection circuit is configured to detect a characteristic(s) of a group of input data signals to be driven onto adjacent signal lines. A characteristic could be, for example, a particular combination of logic levels and/or transitions for, the group of input data signals. The driver adjust circuit is configured to provide a driver adjustment signal based at least in part on a detection signal, that is provided by the detection circuit. A data driver is configured to drive a respective one of the group of input data signals as a respective one of the output data signals, wherein the data driver is adjusted based at least in part on the driver adjustment signal.
    Type: Application
    Filed: August 15, 2011
    Publication date: February 21, 2013
    Applicant: Micron Technology, Inc.
    Inventors: TIMOTHY M. HOLLIS, BRUCE W. SCHOBER
  • Publication number: 20130038346
    Abstract: Apparatus and methods related to data transmission are disclosed. One such apparatus includes a transmitter, a receiver, and a channel. The transmitter includes a pair of current sources and a pair of switches. Each of the switches conducts one of the current sources to the channel in response to input data. The receiver includes a first node configured to receive a signal over the channel. The receiver also includes a resistance generating a voltage drop between the first node and a second node. The receiver further includes a first transistor and a second transistor that are together configured to provide a voltage level to the second node based at least partly on the voltage drop. The resistance provides a negative feedback to center the mean signal level, thereby reducing intersymbol interference.
    Type: Application
    Filed: August 16, 2012
    Publication date: February 14, 2013
    Applicant: MICRON TECHNOLOGY, INC.
    Inventor: Timothy M. Hollis
  • Patent number: 8373436
    Abstract: An apparatus for consolidated data services comprising a plurality of devices, a plurality of data services and a content application programming interface (API). A user API provides user identification for each of the plurality of devices. A feedback API configured to receive data from each of the plurality of devices. A device API configured to provide a client system to one or more of the plurality of devices using one or more of a plurality of device API methods. An update API configured to provide an updated client system to one or more of the plurality of devices using one more of a plurality of update API methods. A web service consolidator configured to control interactions between the content API, the user API, the feedback API, the device API, the update API, a plurality of data services and the plurality of devices.
    Type: Grant
    Filed: March 25, 2011
    Date of Patent: February 12, 2013
    Assignee: Triune Systems, LLC
    Inventors: Amer Atrash, Ross Teggatz, Brett Smith, Wayne Chen
  • Publication number: 20130033288
    Abstract: A semiconductor device includes an impedance control signal generation unit configured to generate an impedance control signal for controlling an impedance value, a first processing unit configured to process the impedance control signal in response to a first setup value and generate a first process signal, a first clock termination unit configured to be coupled with a first clock path and determine an impedance value responding to the impedance control signal, and a second clock termination unit configured to be coupled with a second clock path and determine an impedance value responding to the first process signal.
    Type: Application
    Filed: October 31, 2011
    Publication date: February 7, 2013
    Inventor: Geun-Il LEE
  • Publication number: 20130033287
    Abstract: A balanced single-end impedance control system is disclosed. In a particular embodiment, the circuit includes a first transistor coupled to a first output terminal and a second transistor coupled to a second output terminal. The circuit also includes a third transistor and a fourth transistor, where device characteristics of the third transistor substantially match device characteristics of the first transistor and device characteristics of the fourth transistor substantially match device characteristics of the second transistor. The circuit further includes a first control path and a second control path. The first path is coupled to the third transistor and provides a first rail voltage to control a first gate control voltage of the first transistor. The second control path is coupled to the fourth transistor and provides a second rail voltage to control a second gate control voltage of the second transistor.
    Type: Application
    Filed: August 3, 2011
    Publication date: February 7, 2013
    Applicant: QUALCOMM INCORPORATED
    Inventors: Miao Li, Nam V. Dang, Xiaohua Kong
  • Patent number: 8363508
    Abstract: To include an AL counter that outputs a second ODT signal after counting a clock signal by an additive latency after receiving a first ODT signal, and a counter control circuit that controls the AL counter such that the second ODT signal having the same logic value as a logic value of the first ODT signal at a time of shifting from an asynchronous mode to a synchronous mode is output during a period until when at least the clock signal is input by an additive latency after the shifting. With this configuration, an interruption of an CDT operation can be prevented without separately providing a CKE counter. Therefore, the circuit scale can be reduced and the power consumption can be also reduced.
    Type: Grant
    Filed: August 19, 2010
    Date of Patent: January 29, 2013
    Assignee: Elpida Memory, Inc.
    Inventor: Hiroki Fujisawa
  • Publication number: 20130021056
    Abstract: Described are on-die termination (ODT) systems and methods that facilitate high-speed communication between a driver die and a receiver die interconnected via one or more signal transmission lines. An ODT control system in accordance with one embodiment calibrates and maintains termination resistances and drive currents to produce optimal output swing voltages. Comparison circuitry employed to calibrate the reference resistance is also used to calibrate the drive current. Termination elements in some embodiments are divided into two adjustable resistive portions, both of which are designed to minimize capacitive loading. One portion is optimized to produce a relatively high range of adjustment, while the other is optimized for fine-tuning and glitch-free switching.
    Type: Application
    Filed: September 25, 2012
    Publication date: January 24, 2013
    Applicant: Rambus Inc.
    Inventors: Huy M. Nguyen, Vijay Gadde, Benedict Lau
  • Publication number: 20130015880
    Abstract: A semiconductor device has a ZQ circuit (40) which generates impedance control information and an output buffer having an impedance controlled in response to the impedance control information. A plurality of control bits constituting the impedance control information are serially transferred from the ZQ circuit.
    Type: Application
    Filed: July 10, 2012
    Publication date: January 17, 2013
    Applicant: Elpida Memory, Inc.
    Inventor: Yoshinori HARAGUCHI
  • Publication number: 20130015879
    Abstract: A device includes an output circuit including a plurality of unit buffers, each of the unit buffers having an adjustable impedance; a controller circuit operable to selectively activate at least one of the unit buffers; and an impedance adjustment part operable to adjust the impedance of each of the unit buffers in response to a change of the number of the unit buffers that are selectively activated by the controller circuit.
    Type: Application
    Filed: July 10, 2012
    Publication date: January 17, 2013
    Applicant: ELPIDA MEMORY, INC.
    Inventor: Hiroei ARAKI
  • Patent number: 8354864
    Abstract: A memory system includes a sense amplifier for detecting content of data memory cells by comparison with a voltage stored in a reference cell. The sense amplifier may comprise a comparator, first and second load circuits, and a low impedance circuit. A first input of the comparator is coupled to the low impedance circuit and a reference voltage node. A second input of the comparator is coupled to a data voltage node. The first load circuit loads a reference cell coupled to the reference voltage node. The second load circuit loads a data cell coupled to the data voltage node.
    Type: Grant
    Filed: October 31, 2011
    Date of Patent: January 15, 2013
    Assignee: Silicon Storage Technology, Inc.
    Inventors: Hieu Van Tran, Sang Thanh Nguyen, Hung Quoc Nguyen
  • Publication number: 20130002290
    Abstract: Embodiments of the invention are generally directed to a configurable multi-mode driver and receiver. An embodiment of a communication system includes a communication channel, and a first device and a second device coupled with the communication channel. The first device includes a driver apparatus to drive data signals on the communication channel, the driver apparatus including circuits to receive and drive the data signals, where the circuits are configurable for termination resistance of the driver circuit apparatus, and each of the plurality of circuits is comprised of one or more circuit units, the circuit units being configurable for equalization control of the driver apparatus. The second device includes a receiver to receive data signals from the communication channel as an input. Either the first device or the second device includes configurable circuit elements to provide signal reflection control for the system.
    Type: Application
    Filed: June 30, 2011
    Publication date: January 3, 2013
    Inventors: Srikanth Gondi, Roger Isaac
  • Publication number: 20130002291
    Abstract: A semiconductor memory device includes a first memory chip including a first on die termination (ODT) unit electrically connected to a first pad, the first pad being connected to a first terminal to receive a first signal, and a second memory chip including a second ODT unit electrically connected to a second pad, the second pad being connected to the first terminal to receive the first signal, the first ODT unit being configured to turn on/off according to a memory operation, the second ODT unit being configured to turn off regardless of the memory operation, and the first and second ODT units are switchable.
    Type: Application
    Filed: May 15, 2012
    Publication date: January 3, 2013
    Inventor: Joon-Young PARK
  • Patent number: 8344752
    Abstract: A semiconductor integrated circuit includes an impedance control signal generation block configured to transmit first impedance control signals and second impedance control signals through same signal lines at predetermined time intervals, and input/output blocks configured to separately receive the first impedance control signals and the second impedance control signals at corresponding time intervals and perform a data input/output operation based on set impedance.
    Type: Grant
    Filed: December 31, 2010
    Date of Patent: January 1, 2013
    Assignee: SK Hynix Inc.
    Inventor: Seong Hwi Song
  • Patent number: 8344704
    Abstract: A method and apparatus for allowing the user of a power generator coupled to a time-varying load, to define an alternative reference impedance to enable on or more metrics to be provided relative to the alternative reference impedance. The metrics, for example, may provide indicia of performance of the power generator system. One illustrative embodiment provides a power delivery system that applies power to a plasma chamber to create a plasma therein; determines a reference impedance of the plasma at an operating condition; and controls the power delivery system based on the determined reference impedance.
    Type: Grant
    Filed: December 31, 2009
    Date of Patent: January 1, 2013
    Assignee: Advanced Energy Industries, Inc.
    Inventor: Gideon Van Zyl
  • Patent number: 8344753
    Abstract: A terminal resistor apparatus includes an input-side switch, an input-side terminal resistor, an output-side switch, and an output-side terminal resistor. When a plurality of the terminal resistor apparatus are connected, the input-side switch of the first terminal resistor apparatus will be conducted so that the input-side terminal resistor will be connected, but the output-side switch will not be conducted so that the output-side terminal resistor will not be connected. The input-side switch of the last terminal resistor apparatus will not be conducted so that the input-side terminal resistor will not be connected, but the output-side switch will be conducted so that the output-side terminal resistor will be connected. The input-side switches of the other terminal resistor apparatus will not be conducted so that the input-side terminal resistors will not be connected, and the output-side switches will not be conducted so that the output-side terminal resistors will not be connected.
    Type: Grant
    Filed: September 13, 2011
    Date of Patent: January 1, 2013
    Assignee: Delta Electronics, Inc.
    Inventors: Jen-Te Liang, Chih-Hung Tsai
  • Patent number: 8344761
    Abstract: Included are embodiments of a 3-level line driver. At least one embodiment of a method includes generating a repetitive wave; receiving an input signal and a complement of the input signal; providing a 3-level output signal; and filtering a feedback signal, the means for filtering including at least one of the following: a 0th order filter, and an even order filter.
    Type: Grant
    Filed: September 11, 2009
    Date of Patent: January 1, 2013
    Assignee: Ikanos Communications, Inc.
    Inventors: Kadaba Lakshmikumar, Sander Laurentius Johannes Gierkink
  • Patent number: 8344751
    Abstract: An impedance code generation circuit includes a first code generation unit configured to compare a voltage of a calibration node with a reference voltage and generate a first impedance code, a code modification unit configured to generate a modified impedance code by performing an operation on the first impedance code according to a setting value, and a second code generation unit configured to generate a second impedance code based on the modified impedance code.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: January 1, 2013
    Assignee: Hynix Semiconductor Inc.
    Inventor: Jin-Hee Cho
  • Publication number: 20120326745
    Abstract: A differential buffer circuit having increased output voltage swing includes a differential input stage including at least first and second transistors, the first and second transistors being operative to receive first and second signals, respectively. The buffer circuit further includes a bias stage connected between the differential input stage and a first voltage source. The bias stage is operative to generate a quiescent current as a function of a third signal supplied to the bias stage. A load circuit is connected between a second voltage source and the differential input stage, first and second differential outputs of the buffer circuit being generated at a junction between the load circuit and the differential input stage. The load circuit includes first and second switching elements coupled with the first and second transistors, respectively.
    Type: Application
    Filed: June 21, 2011
    Publication date: December 27, 2012
    Applicant: LSI CORPORATION
    Inventors: Makeshwar Kothandaraman, Pankaj Kumar, Paul K. Hartley, John Christopher Kriz
  • Publication number: 20120326746
    Abstract: Described herein are a method and an apparatus for dynamically switching between one or more finite termination impedance value settings to a memory input-output (I/O) interface of a memory in response to a termination signal level. The method comprises: setting a first termination impedance value setting for a termination unit of an input-output (I/O) interface of a memory; assigning the first termination impedance value setting to the termination unit when the memory is not being accessed; and switching from the first termination impedance value setting to a second termination impedance value setting in response to a termination signal level.
    Type: Application
    Filed: June 26, 2012
    Publication date: December 27, 2012
    Inventors: James A. McCall, Kuljit S. Bains
  • Patent number: 8339156
    Abstract: A method is disclosed for controlling an output impedance of an electronic device of the type having an impedance control terminal to which an external load is to be connected such that a predetermined value of the voltage at the impedance control terminal controls the output impedance of the device. The method is comprised of comparing a reference voltage to a voltage at the impedance control terminal. A variable count signal representing a count value is produced in response to the comparing. The impedance of a variable impedance circuit is varied in response to the count signal, wherein the impedance of the variable impedance circuit controls the voltage at the impedance control terminal. A device connected in parallel with the variable impedance circuit is periodically operated to change (increase/decrease) the impedance of the variable impedance circuit. An apparatus for performing the method is also disclosed.
    Type: Grant
    Filed: February 14, 2011
    Date of Patent: December 25, 2012
    Assignee: Micron Technology, Inc.
    Inventor: Kang Yong Kim
  • Publication number: 20120319726
    Abstract: A terminal resistor apparatus includes an input-side switch, an input-side terminal resistor, an output-side switch, and an output-side terminal resistor. When a plurality of the terminal resistor apparatus are connected, the input-side switch of the first terminal resistor apparatus will be conducted so that the input-side terminal resistor will be connected, but the output-side switch will not be conducted so that the output-side terminal resistor will not be connected. The input-side switch of the last terminal resistor apparatus will not be conducted so that the input-side terminal resistor will not be connected, but the output-side switch will be conducted so that the output-side terminal resistor will be connected. The input-side switches of the other terminal resistor apparatus will not be conducted so that the input-side terminal resistors will not be connected, and the output-side switches will not be conducted so that the output-side terminal resistors will not be connected.
    Type: Application
    Filed: September 13, 2011
    Publication date: December 20, 2012
    Inventors: Jen-Te LIANG, Chih-Hung Tsai
  • Patent number: 8334706
    Abstract: An impedance calibration mode control circuit includes: a first signal generating unit configured to generate a first calibration control signal in response to a ZQ calibration command received after a power-up operation; and a second signal generating unit configured to generate a second calibration control signal during a refresh operation of a semiconductor device.
    Type: Grant
    Filed: December 22, 2010
    Date of Patent: December 18, 2012
    Assignee: Hynix Semiconductor Inc.
    Inventor: In-Jun Moon
  • Patent number: 8331167
    Abstract: A data output apparatus includes a driver driving unit configured to generate driving signals by using input data when a data output enable signal is enabled, a data driver unit configured to drive an output terminal to a level corresponding to the input data in response to the driving signals to generate output data, and an output data level control unit configured to open a current path to control a level of the output data, wherein the current path is different from a current path for driving the output terminal to a level corresponding to the input data.
    Type: Grant
    Filed: December 31, 2008
    Date of Patent: December 11, 2012
    Assignee: SK hynix Inc.
    Inventor: Ho-Uk Song
  • Patent number: 8330486
    Abstract: A data line termination circuit includes a swing-width sensing unit configured to sense a swing width of a voltage of a data line and output a sensed signal, and a variable termination unit configured to adjust a termination resistance value of the data line in response to the sensed signal. The swing-width sensing unit can sense if the swing width is less than or greater than a predetermined swing width, and the swing width of the voltage of the data line can be reduced or increased to maintain the voltage of the data line within a predetermined range.
    Type: Grant
    Filed: November 30, 2010
    Date of Patent: December 11, 2012
    Assignee: Hynix Semiconductor Inc.
    Inventors: Yong Kee Kwon, Hyung Dong Lee
  • Publication number: 20120306531
    Abstract: A semiconductor device includes a first input terminal receiving a termination resistance control signal, and a termination resistance circuit that is able to be controlled to be turned on or off by the termination resistance control signal. The termination resistance circuit is turned off, irrespective of a level of said termination resistance control signal when the semiconductor device outputs data in response to a read command.
    Type: Application
    Filed: August 20, 2012
    Publication date: December 6, 2012
    Applicant: Elpida Memory, Inc.
    Inventor: Atsuo Koshizuka
  • Patent number: 8324947
    Abstract: Provided is an output apparatus that outputs an output signal corresponding to an input signal, comprising a plurality of drivers that each output an intermediate signal having a waveform corresponding to the input signal; an adding section that adds together the intermediate signals output from the drivers and outputs the result as the output signal; and a control section that controls a difference in delay amount, which is from when the input signal begins to change to when the intermediate signal begins to change, among the drivers according to a designated slew rate.
    Type: Grant
    Filed: June 6, 2011
    Date of Patent: December 4, 2012
    Assignee: Advantest Corporation
    Inventor: Hiroki Ichikawa
  • Patent number: 8324936
    Abstract: Differential current driving type transmitter and receiver, and an interface system having the transmitter and receiver. The transmitter includes a current source, a current direction selecting block, and a balancing switch block. The current source sources currents to a pair of transmission lines or sinks currents flowing through the pair of transmission lines. The current direction selecting block transfers a current flowing from the current source to one transmission line of the pair of transmission lines and a current flowing through the other transmission line of the pair of transmission lines to the current source. The balancing switch block initializes the pair of transmission lines to a balanced state.
    Type: Grant
    Filed: July 7, 2009
    Date of Patent: December 4, 2012
    Assignee: Silicon Works Co., Ltd.
    Inventors: Jun Ho Kim, Young Soo Ryu, Ju Pyo Hong, Jung Hwan Choi
  • Patent number: 8324928
    Abstract: A calibration circuit includes a pad connected between an external resistor connected to a first voltage source and a first node, a first resistor unit connected between the first node and a second voltage source, a second resistor unit connected between a second node and the second voltage source, a first control unit for generating and outputting a first output signal, a first pull-down circuit connected between the second node and the first voltage source, a second pull-down circuit connected between a third node and the first voltage source, a second control unit for generating and outputting a second output signal, and a pull-up circuit connected between the third node and the second voltage source.
    Type: Grant
    Filed: February 14, 2011
    Date of Patent: December 4, 2012
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jun-bae Kim
  • Patent number: 8324927
    Abstract: An input/output (I/O) cell including one or more driver-capable segments and one or more on-die termination (ODT) capable segments. The I/O cell may be configured as an output driver in a first mode and Thevenin equivalent termination in a second mode.
    Type: Grant
    Filed: December 16, 2010
    Date of Patent: December 4, 2012
    Assignee: LSI Corporation
    Inventors: Dharmesh Bhakta, Hong-Him Lim, Cheng-Gang Kong, Todd Randazzo
  • Publication number: 20120299619
    Abstract: Described are amplifiers that facilitate high-speed communication with calibrated drive strength and termination impedance. Drivers and termination elements can be divided into a number N of parallel portions, one or more of which can be disabled and updated without interfering with signal (e.g., clock or data) transmission. Some embodiments identify inactive elements by examining incoming signals.
    Type: Application
    Filed: August 6, 2012
    Publication date: November 29, 2012
    Applicant: Rambus Inc.
    Inventors: Huy M. Nguyen, Vijay Gadde, Sivakumar Doriaswamy