Slope Control Of Leading Or Trailing Edge Of Rectangular (e.g., Clock, Etc.) Or Pulse Waveform Patents (Class 327/170)
  • Patent number: 7952383
    Abstract: There is provided a semiconductor device that includes: an output buffer capable of adjusting an impedance based on an impedance adjustment signal, and a through-rate control circuit that adjusts a through rate of the output buffer based on at least the impedance adjustment signal, wherein the through-rate control circuit sets a relatively high through rate when the impedance adjustment signal designates a relatively low impedance, and sets a relatively low through rate when the impedance adjustment signal designates a relatively high impedance.
    Type: Grant
    Filed: August 21, 2009
    Date of Patent: May 31, 2011
    Assignee: Elpida Memory, Inc.
    Inventor: Masaru Kodato
  • Publication number: 20110115537
    Abstract: Embodiments include circuit devices and methods for re-clocking an input signal. In an embodiment, a circuit device includes a data storage element having a data input to receive a digital data stream having a first clock rate and including a clock input to receive a clock signal having a second clock rate. The data storage element further includes logic to adjust edge timing of transitions within the digital data stream based on the clock signal to produce a modulated output signal having a power spectrum with spectral nulls at a desired frequency and its harmonics without changing an average data rate.
    Type: Application
    Filed: November 18, 2009
    Publication date: May 19, 2011
    Applicant: SILICON LABORATORIES, INC.
    Inventors: Michael Robert May, Russell Croman, Younes Djadi, Scott Thomas Haban
  • Publication number: 20110109361
    Abstract: The semiconductor device includes an output driver and a characteristic switching circuit that switches characteristics of the output driver. The characteristic switching circuit mutually matches a rising time and a falling time of an output signal output from the output driver, when a power voltage supplied to a power line is a first voltage, with a rising time and a falling time of the output signal output from the output driver, when the power voltage supplied to the power line is a second voltage. As a result, an increase in an influence of a harmonic component or a crosstalk when the power voltage is reduced does not occur. Moreover, because a receiving condition on a receiver side does not change even when the power voltage is reduced, signal transmission and reception can be performed correctly irrespective of the power voltage.
    Type: Application
    Filed: November 4, 2010
    Publication date: May 12, 2011
    Applicant: Elpida Memory, Inc.
    Inventor: Yoji Nishio
  • Patent number: 7940102
    Abstract: Consistent with an example embodiment, an edge-rate control circuit arrangement (300) for an I2C bus application comprises a first circuit stage (10, M1, M3), responsive to a state transition of a received signal. A second circuit stage (310, 25, 20, 35, 45, M4, ESD) is responsive to the state transition of the received signal and includes drive circuitry (M4) that is activated in response to the state transition of the received signal in order to provide an edge-transition signal for an I2C bus, and regulation circuitry (310, R1, R2, M0, M2) adapted to control the drive circuit and regulate a transition rate for the edge-transition signal, the transition rate being greater than a transition rate of the received signal at the first circuit stage and greater than a minimum and less than a maximum transition rate designated for communication on the I2C bus.
    Type: Grant
    Filed: April 30, 2010
    Date of Patent: May 10, 2011
    Assignee: NXP B.V.
    Inventors: Alma Anderson, Joseph Rutkowski, Dave Oehler
  • Patent number: 7940101
    Abstract: An apparatus for slew rate control using a plurality of discrete slew rate levels. The apparatus includes a load switch and a switch controller. The load switch outputs a load voltage to a load. The switch controller generates a switch control signal in response to an enable signal. The switch control signal controls operation of the load switch. The switch controller controls a slew rate of the load switch according to a plurality of discrete slew rate levels.
    Type: Grant
    Filed: August 28, 2008
    Date of Patent: May 10, 2011
    Assignee: Avago Technologies ECBU IP (Singapore) Pte. Ltd.
    Inventors: Abhay Kumar Rai, Ronald Dean Gillingham
  • Patent number: 7928784
    Abstract: A circuit for independently controlling slew and propagation delay of a current DAC is provided. The circuit applies dual slope technique with feed-back control the gate (or control electrode) of a switching transistor to make propagation delay independent control from rise/fall slew rate. This allows one to adjust propagation delay and current slew rate separately to achieve better performance.
    Type: Grant
    Filed: June 26, 2009
    Date of Patent: April 19, 2011
    Assignee: Texas Instruments Incorporated
    Inventors: Huijuan Li, Abidur Rahman, Chienyu Huang
  • Publication number: 20110084745
    Abstract: An embodiment of a slew-rate enhancement output stage is disclosed. A first slew-rate enhancement circuit receives a first control voltage and outputs a first voltage. A second slew-rate enhancement circuit receives a second control voltage and outputs a second voltage. A first PMOS transistor includes a first first terminal coupled to a high voltage source, a first control terminal receiving the first voltage, and a first second terminal coupled to a voltage output terminal. A first NMOS transistor includes a second first terminal coupled to the voltage output terminal, a second control terminal for receiving the second voltage, and a second second terminal coupled to a low voltage source. The first voltage is higher than the first control voltage, and the second voltage is lower than the second control voltage.
    Type: Application
    Filed: October 13, 2009
    Publication date: April 14, 2011
    Applicant: HIMAX TECHNOLOGIES LIMITED
    Inventors: Hung-Yu Huang, Chin-Tien Chang
  • Publication number: 20110084746
    Abstract: This document discusses, among other things, a system and method for reducing electromagnetic interference of a switched signal. In an example, a switched input signal can be received at an input and a transition rate of an edge rate controlled, switched output signal can be controlled in response to the received switched input signal.
    Type: Application
    Filed: October 7, 2010
    Publication date: April 14, 2011
    Inventor: William D. Llewellyn
  • Patent number: 7923982
    Abstract: A semiconductor integrated circuit is provided with a voltage level detector which detects a voltage level of a signal wire, and a transition time detector which detects a time length of a transition period during which the signal wire changes from an inactive voltage state to an active voltage state based on the voltage level detected by the voltage level detector. The voltage level detector detects the voltage level of the signal wire during the transition period.
    Type: Grant
    Filed: August 29, 2006
    Date of Patent: April 12, 2011
    Assignee: Panasonic Corporation
    Inventor: Masaya Sumita
  • Patent number: 7919988
    Abstract: An output circuit includes a pre-driving unit configured to drive an input signal by using a different driving power according to an output operation mode and generate pull-up and pull-down signals corresponding to the resultant input signal and an output driving unit configured to output data in response to the pull-up and pull-down signals.
    Type: Grant
    Filed: June 29, 2009
    Date of Patent: April 5, 2011
    Assignee: Hynix Semiconductor Inc.
    Inventor: Seung-Min Oh
  • Patent number: 7915937
    Abstract: Disclosed herein are circuitry and methods for improving differential signals that cross power domains. In an example embodiment, the power supply domain boundary along the output paths that generate the differential signal is staggered, such that the boundary occurs at an odd numbered stage in one differential output path and at an even numbered stage in the other differential output. Defining the power supply domain boundary in this manner can help ensure that the same logical state is present at the boundary in either of the differential output paths. This same logic signal should affect subsequent stages similarly from a speed perspective, and so should similarly affect the differential signals generated by each of the output paths.
    Type: Grant
    Filed: September 11, 2008
    Date of Patent: March 29, 2011
    Assignee: Micron Technology, Inc.
    Inventor: Bryce Cook
  • Patent number: 7916098
    Abstract: A plasma display apparatus and a method of driving the same are disclosed. The plasma display apparatus includes a plasma display panel including a scan electrode, and a scan driver that supplies a setup pulse to the scan electrode. The setup pulse gradually rises to a first voltage level with a first slope, rises from the first voltage level to a second voltage level with a second slope smaller than the first slope, and rises from the second voltage level to a third voltage level with a third slope different from the second slope.
    Type: Grant
    Filed: July 20, 2007
    Date of Patent: March 29, 2011
    Assignee: LG Electronics Inc.
    Inventors: Jeong Pil Choi, Kyu Choon Cho, Woo Chang Jung
  • Publication number: 20110058623
    Abstract: Apparatus for generating a first signal (e.g., a pulse) including a current source adapted to generate a current based on a second signal that defines an amplitude of the current and a third signal that defines the timing of an amplitude change of the current, and an impedance element through which the current flows to generate the first signal. The impedance element may comprise a resonator having a resonant frequency approximate the center of the first signal frequency spectrum. An LO may be used to generate the third signal to control the timing of the amplitude change of the current. A detector may enable the current source in response to detecting a defined steady-state condition of the LO clock signal, and may disable the current source in response to the completion of the first signal. A controller may generate the second signal to control the current amplitude so as to perform power control and/or other functions.
    Type: Application
    Filed: September 11, 2009
    Publication date: March 10, 2011
    Applicant: QUALCOMM Incorporated
    Inventors: Anthony F. Segoria, Jorge A. Garcia
  • Patent number: 7902858
    Abstract: A calibration circuit includes: a replica buffer that drives a calibration terminal; a pre-emphasis circuit connected in parallel to the replica buffer; and an up-down counter that changes impedances of the replica buffer and the pre-emphasis circuit. A replica control circuit causes the replica buffer to conduct based on an impedance code, and a pre-emphasis control circuit causes the pre-emphasis circuit to conduct in an initial stage of a conducting period of the replica buffer. Thereby, even when an external resistor is shared among a plurality of semiconductor devices, for example, a voltage appearing in the calibration terminal can be stabilized at a higher speed.
    Type: Grant
    Filed: July 9, 2008
    Date of Patent: March 8, 2011
    Assignee: Elpida Memory, Inc.
    Inventors: Shunji Kuwahara, Hiroki Fujisawa
  • Patent number: 7902875
    Abstract: This document discusses, among other things, output slew rate control. Methods and structures are described to provide slew rate control of an output driver circuit such as a DRAM output driver on a die. A selectable combination of series coupled transistors are configured as a parallel array of complementary inverter pairs to provide a divided voltage to a calibrator. The calibrator is configured to respond to a differential voltage to adjust the divided voltage such that the differential voltage is forced to zero. The calibrator outputs a plurality of discrete signals from an up/down counter to switch on and off the individual transistors of the parallel array to increase and decrease a collective current. In some embodiments, transistor channel currents are modulated to step-adjust a voltage based on a ratio associated with a static resistance. In various embodiments, the divided voltage is an analog voltage based on a resistance associated with trim circuitry.
    Type: Grant
    Filed: November 3, 2006
    Date of Patent: March 8, 2011
    Assignee: Micron Technology, Inc.
    Inventor: Shizhong Mei
  • Patent number: 7902883
    Abstract: In one embodiment, a system includes a replica driver that includes n-type digital-to-analog converter (NDAC) current sources. The replica driver can produce a reference voltage based on current supplied by the NDAC current sources. The system includes driver fingers that are coupled to the replica driver and each include a driver bias circuit and an output driver. The driver bias circuit includes an operational amplifier (op-amp) that can adjust current-source gate voltage in the output driver to produce voltages at output nodes of the driver fingers that approximately match the reference voltage produced by the replica driver.
    Type: Grant
    Filed: June 22, 2009
    Date of Patent: March 8, 2011
    Assignee: Fujitsu Limited
    Inventor: Yasuo Hidaka
  • Patent number: 7902892
    Abstract: A control loop has a control slope associated therewith. The control loop is provided to control a unit under control. A method of regulating the control slope comprises the step of measuring the control slope of the control loop and modifying a parameter associated with the unit under control in order to maintain the control slope within a desired range. Lock of the control loop is therefore maintained.
    Type: Grant
    Filed: September 11, 2006
    Date of Patent: March 8, 2011
    Assignee: Freescale Semiconductor, Inc.
    Inventors: Patrick Pratt, Denis Dineen, Michael O'Brien
  • Patent number: 7898287
    Abstract: An input buffer includes a delay compensation unit for combining (a) a first signal obtained by buffering an input signal using another signal, which is out of phase with the input signal, with (b) a second signal obtained by buffering the input signal using a reference voltage signal, to output a third signal.
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: March 1, 2011
    Assignee: Hynix Semiconductor Inc.
    Inventors: Ki Ho Kim, Kang Seol Lee
  • Publication number: 20110043291
    Abstract: Techniques for generating quadrature signals from a local oscillator signal, wherein the generated quadrature signals have a frequency half of the local oscillator frequency. In an exemplary embodiment, two oscillators, e.g., injection locked oscillators, are provided, each oscillator having a load, a cross-coupled transistor pair, an integrating capacitor, and current injection transistors. A differential pair is coupled to the leads of each of the integrating capacitors, and the drains of the differential pair are coupled to the outputs of the other oscillator to help increase the slew rate of the output voltages of the other oscillator. The inputs to the differential pair may be first amplified to improve the gain of the differential pair. In another exemplary embodiment, the power consumption of the differential pair may be reduced by operating them in a discontinuous mode, e.g., by coupling the source voltages of the differential pair to corresponding delayed versions of the drain voltages.
    Type: Application
    Filed: December 8, 2009
    Publication date: February 24, 2011
    Applicant: QUALCOMM INCORPORATED
    Inventor: Russell J. Fagg
  • Patent number: 7893751
    Abstract: An integrated circuit includes a transistor. During operation a current slew-rate is determined based on a duration the transistor has been conducting and a current flowing through the transistor. The transistor can then be controlled to switch to its non-conducting state using the slew-rate.
    Type: Grant
    Filed: January 30, 2009
    Date of Patent: February 22, 2011
    Assignee: Infineon Technologies Austria AG
    Inventor: Christoph Deml
  • Publication number: 20110037752
    Abstract: An embodiment of a discharge circuit comprises an output circuit with one output connected to an electrical load to absorb a discharge current given by the load when a logic signal commands a discharge of the load. The discharge circuit also comprises a control circuit to give the output circuit an appropriate control signal so that a slope of an output potential of the output circuit diminishes gradually when the logic signal commands a discharge of the load. Limiting the slope of the output potential gradually (and not suddenly) may limit the electromagnetic radiation generated by these variations.
    Type: Application
    Filed: October 27, 2010
    Publication date: February 17, 2011
    Applicant: STMicroelectronics, SA
    Inventors: François RAVATIN, Gilles Troussel
  • Publication number: 20110025391
    Abstract: A technique for a delay measurement system to measure the skews in a clock distribution network is presented. It uses the principle of sub-sampling to measure and amplify small clock skews and determine an estimate of clock skew by further manipulation if these sampled measurements. The technique can be applied to measure clock skew on a computer chip, between bit-line of a communication bus, or between elements connected by an electronic or optical interconnect.
    Type: Application
    Filed: July 29, 2009
    Publication date: February 3, 2011
    Inventors: Bharadwaj Amrutur, Pratap Kumar Das
  • Patent number: 7880512
    Abstract: In an output driver circuit, a replica circuit includes seventh and eighth transistors corresponding to first and second transistors, respectively, ninth and tenth transistors corresponding to third or fifth, and fourth or sixth transistors in a driver circuit, respectively, and a resistor corresponding to a termination resistor. A reference voltage and a voltage of a node between the ninth transistor and the resistor are input to an operational amplifier, and an output signal of the operational amplifier is input to gates of the first and seventh transistors.
    Type: Grant
    Filed: December 2, 2008
    Date of Patent: February 1, 2011
    Assignee: Kawasaki Microelectronics, Inc.
    Inventor: Daishi Takeuchi
  • Patent number: 7880521
    Abstract: A differential driver includes first and second pull-up resistors respectively connected to first and second output terminals, a plurality of differential-input transistor pairs connected each to the first and second output terminals, current sources connected each to the differential-input transistor pairs, and a slew rate controller adapted to generate differential input signals to be applied each to the differential-input transistor pairs in response to an input signal. The slew rate controller may output the differential input signals simultaneously or sequentially.
    Type: Grant
    Filed: August 2, 2007
    Date of Patent: February 1, 2011
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Hitoshi Okamura, Byung-Hyun Lim
  • Patent number: 7880523
    Abstract: An apparatus and method of providing a pulse width modulated signal that is responsive to a current are disclosed. A circuit according to aspects of the present invention includes a capacitor to convert a first current to a first voltage on the capacitor during a first time duration and to discharge a second current from the capacitor to change the first voltage to a second voltage during a second time duration. A comparator is also included and is coupled to an output of the capacitor to compare a voltage on the capacitor to a reference voltage during the second time duration to change a pulse width of a periodic output signal in response to an input current.
    Type: Grant
    Filed: October 29, 2009
    Date of Patent: February 1, 2011
    Assignee: Power Integrations, Inc.
    Inventor: Zhao-Jun Wang
  • Patent number: 7876630
    Abstract: Circuits, methods, and apparatus that isolate an input register from spurious transitions on a DQS signal. One example receives an enable signal from a core. A logic circuit, which may be referred to as a one-half period circuit, shortens enable pulses at their front end by one-half a period. The shortened enable signal is passed to a storage element such as a register. Active pulses of the shortened enable signal clear the register, which provides a control signal closing a switch, such as an AND gate. The switch passes the DQS signal to the input register when closed and isolates the input register from the DQS signal when open. The shortened enable signal prevents the switch from opening early and passing spurious transitions on the DQS signal, for example during back-to-back non-consecutive read cycles.
    Type: Grant
    Filed: November 6, 2007
    Date of Patent: January 25, 2011
    Assignee: Altera Corporation
    Inventors: Philip Clarke, Andrew Bellis, Yan Chong, Joseph Huang, Michael H. M. Chu
  • Patent number: 7876133
    Abstract: An output driver circuit can include at least a first driver transistor having a source-drain path coupled between a first power supply node and an output node. A first variable current supply can generate a current having at least one component that is inversely proportional to a power supply voltage. A first driver switch element can be coupled in series with the first variable current supply between a gate of the at least first driver transistor and a second power supply node.
    Type: Grant
    Filed: September 27, 2007
    Date of Patent: January 25, 2011
    Assignee: Cypress Semiconductor Corporation
    Inventors: Alan McLaughlin, Gabriel Li
  • Publication number: 20110006614
    Abstract: A first energy generating system comprises a ferromagnetic generator coupled to a voltage controlled switch. The ferromagnetic generator includes a ferromagnetic element generating a magnetic field and positioned within a pulse generating coil and near an explosive charge. Detonation of the explosive charge decreases the magnetic field and induces a pulse of electric energy in the pulse generating coil. When the magnitude of the electric energy reaches a certain level, the voltage controlled switch closes. A second energy generating system comprises a flux compression generator coupled to a voltage controlled switch. The flux compression generator includes a inductance coil generating a magnetic field within a metallic armature that includes an explosive charge. Detonation of the explosive charge changes the magnetic field and induces a pulse of electric energy in the inductance coil. When the magnitude of the electric energy reaches a certain level, the voltage controlled switch closes.
    Type: Application
    Filed: February 23, 2010
    Publication date: January 13, 2011
    Applicant: LOKI INCORPORATED
    Inventors: Jason Baird, Sergey Shkuratov
  • Patent number: 7868676
    Abstract: A driver circuit includes a pre-driver and an output driver. The pre-driver is coupled to receive an input signal and to generate first and second pre-driver output signals in response to the input signal. The output driver generates a driver output signal and includes first and second switches, a native mode transistor, and a driver output. The first switch has a first control terminal coupled to receive the first pre-driver output signal. The second switch has a second control terminal coupled to receive the second pre-driver output signal. The native mode transistor is coupled in series between the first switch and the second switch and has a third control terminal coupled to receive the voltage reference signal. The driver output is coupled between the native mode transistor and the second switch to output the driver output signal.
    Type: Grant
    Filed: August 20, 2010
    Date of Patent: January 11, 2011
    Assignee: OmniVision Technologies, Inc.
    Inventors: Yun-Hak Koh, Charles Qingle Wu
  • Publication number: 20100327928
    Abstract: A circuit for independently controlling slew and propagation delay of a current DAC is provided. The circuit applies dual slope technique with feed-back control the gate (or control electrode) of a switching transistor to make propagation delay independent control from rise/fall slew rate. This allows one to adjust propagation delay and current slew rate separately to achieve better performance.
    Type: Application
    Filed: June 26, 2009
    Publication date: December 30, 2010
    Applicant: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Huijuan Li, Abidur Rahman, Chienyu Huang
  • Patent number: 7859317
    Abstract: Clock generation circuitry is arranged in stages so as to convert a slow slew rate input signal into a high slew rate clock signal in a low power environment. Each stage includes a capacitor and an inverter, both fed by respective current mirrors. The capacitor is trickle-charged through its current mirror, and charge of the capacitor is dumped onto an output of the stage at a controlled timing. Two or more such stages may be provided, so as to improve the slew rate of both of the leading and trailing edges of the clock signal, and also so as to provide a convenient source of timing for dumping charge of each capacitor. Each stage might also include a diode switchably connected across the capacitor, so as to discharge the capacitor at appropriate timings, to reduce interference on succeeding stages that might otherwise be caused by residual charge on the capacitor.
    Type: Grant
    Filed: April 16, 2008
    Date of Patent: December 28, 2010
    Assignee: Marvell International Ltd.
    Inventors: Paul E. Stevenson, Nathan Enger, Jon E. Tourville
  • Patent number: 7839200
    Abstract: Semiconductor device and data outputting method of the same includes an on die thermal sensor (ODTS) configured to output temperature information by detecting an internal temperature of the semiconductor device and an output driver configured to control a slew rate depending on the temperature information and output data.
    Type: Grant
    Filed: May 30, 2008
    Date of Patent: November 23, 2010
    Assignee: Hynix Semiconductor Inc.
    Inventors: Jae-Hyuk Im, Kee-Teok Park
  • Publication number: 20100271096
    Abstract: A rising edge or a falling edge is finely adjusted, or a dead time and a period are adjusted with high accuracy. A waveform processing circuit includes: an integration circuit 11 receiving a rectangular or substantially-rectangular pulse and outputting a gradually increasing or decreasing signal obtained by integrating the pulse signal; a reference signal output circuit 12 outputting a constant value or a varying value as a reference signal; and a comparison circuit 13 comparing the output of the integration circuit with the output of the reference signal output circuit and outputting a pulse rising or falling at a timing when the difference between the outputs varies.
    Type: Application
    Filed: June 1, 2008
    Publication date: October 28, 2010
    Applicant: Nagasaki University, National University Corporation
    Inventor: Fujio Kurokawa
  • Patent number: 7821289
    Abstract: A data output driving circuit capable of optimizing a slew rate of data according to the variation of operational conditions and a method for controlling a slew rate thereof includes a slew rate control signal generating unit configured to generate slew rate control signals by using a code signal, and a plurality of drivers configured to output data by driving the data at a slew rate set according to the slew rate control signals.
    Type: Grant
    Filed: July 29, 2008
    Date of Patent: October 26, 2010
    Assignee: Hynix Semiconductor Inc.
    Inventor: Dong-Uk Lee
  • Publication number: 20100264970
    Abstract: Consistent with an example embodiment, an edge-rate control circuit arrangement (300) for an I2C bus application comprises a first circuit stage (10, M1, M3), responsive to a state transition of a received signal. A second circuit stage (310, 25, 20, 35, 45, M4, ESD) is responsive to the state transition of the received signal and includes drive circuitry (M4) that is activated in response to the state transition of the received signal in order to provide an edge-transition signal for an I2C bus, and regulation circuitry (310, R1, R2, M0, M2) adapted to control the drive circuit and regulate a transition rate for the edge-transition signal, the transition rate being greater than a transition rate of the received signal at the first circuit stage and greater than a minimum and less than a maximum transition rate designated for communication on the I2C bus.
    Type: Application
    Filed: April 30, 2010
    Publication date: October 21, 2010
    Applicant: NXP B.V.
    Inventors: Alma ANDERSON, Joseph RUTKOWSKI, Dave OEHLER
  • Publication number: 20100244907
    Abstract: An output buffer utilizes capacitive feedback to control the output slew rate largely independent of load capacitance. The invention slows the rising and falling slew rates and via a capacitance feedback reduces the effect of load capacitance on slew rate, and uses no DC current. Transistor switches are employed to isolate and reduce noise and interaction among the circuit components and functions.
    Type: Application
    Filed: March 25, 2009
    Publication date: September 30, 2010
    Inventors: Nickole A. Gagne, James B. Boomer, Roy L. Yarbrough
  • Patent number: 7804345
    Abstract: A driver circuit provides fast settling times, slew rate control, and power efficiency, while reducing the need for large external capacitors. A voltage reference circuit generates a voltage reference signal. A comparator compares the voltage reference signal and a driver output signal and generates an output high voltage control signal. An output driver includes a first and a second switch that are coupled together. The first and second switches are further coupled to generate the driver output signal in response to coupling the output high voltage control signal to the control terminal of the first switch and coupling an input signal to the control terminal of the second switch.
    Type: Grant
    Filed: January 15, 2008
    Date of Patent: September 28, 2010
    Assignee: OmniVision Technologies, Inc.
    Inventors: Yun-Hak Koh, Charles Qingle Wu
  • Publication number: 20100237919
    Abstract: Edge-rate control circuits and methods are implemented using a variety of arrangements and methods. Using one such method, an output signal of a bus is controlled by decoupling a feedback capacitor (116) from a gate of a transistor (108) using an isolation switch (106). The transistor (108) is used to control the output signal. A predetermined amount of charge is removed from the feedback capacitor (116) using a charge distribution capacitor (114) that is selectively coupled to the feedback capacitor (116) using a switch (112). The switch (112) is enabled in response to the output signal reaching an output voltage and disabled in response to the charge distribution capacitor (114) reaching a reference voltage.
    Type: Application
    Filed: March 31, 2007
    Publication date: September 23, 2010
    Applicant: NXP B.V.
    Inventors: Joseph Rutkowski, Alma Anderson
  • Patent number: 7800416
    Abstract: A data output circuit includes a pre-driving block configured to receive input data, generate a plurality of pull-up signals and pull-down signals, and change enable times of the pull-up signals and the pull-down signals in response to a plurality of control signals, and a main driving block configured to generate output data in response to the pull-up signals and the pull-down signals.
    Type: Grant
    Filed: December 22, 2008
    Date of Patent: September 21, 2010
    Assignee: Hynix Semiconductor Inc.
    Inventors: Yong Ju Kim, Sung Woo Han, Hee Woong Song, Ic Su Oh, Hyung Soo Kim, Tae Jin Hwang, Hae Rang Choi, Ji Wang Lee, Jae Min Jang, Chang Kun Park
  • Patent number: 7795942
    Abstract: A stage by stage delay current-summing slew rate controller includes a delay controller, a delay cell array, a current source array, a switch array, a load. The delay cell array includes N delay cells, the switch array includes N switches, and the switch includes N current sources, wherein N>1. The delay controller is connected with the control ports of the delay cells respectively, and the delay cells are connected with the control terminal of the switches respectively. One of the connecting terminals of the switch is connected with the output end of the current source, and the other end of the connecting terminals of the switch is connected with one end of the load, and the other end of the load is connected to the ground.
    Type: Grant
    Filed: May 31, 2009
    Date of Patent: September 14, 2010
    Assignee: IPGlobal Microelectronics (SiChuan) Co., Ltd.
    Inventors: Yong Quan, Guosheng Wu
  • Patent number: 7795904
    Abstract: A switching circuit includes a first transistor and a driver circuit. The first transistor has a first current electrode coupled to a first power supply voltage terminal to receive a first power supply voltage, a control electrode, and a second current electrode coupled to an output terminal. The driver circuit has an output coupled to the control electrode of the first transistor, the driver circuit for providing a bias current to the control electrode of the first transistor that is proportional to an inverse of a square root of a voltage between the first current electrode and the control electrode of the first transistor. A voltage at the output terminal increases linearly during a turn-on period of the first transistor.
    Type: Grant
    Filed: August 31, 2009
    Date of Patent: September 14, 2010
    Inventor: Thierry Sicard
  • Patent number: 7786778
    Abstract: A driver circuit includes a first transistor having a first node coupled to a high supply voltage and a second node coupled to an output node, wherein the first transistor passes the high supply voltage to the output node based on a first gate voltage on a gate of the first transistor. The driver circuit also includes a second transistor having a first node coupled to a low supply voltage and a second node coupled to the output node of the driver circuit, wherein the second transistor passes the low voltage to the output node based on a second gate voltage on a gate of the second transistor. The driver circuit further includes a logic block configured to control a slew rate of an output signal Vout at the output node by controlling a slew rate of the first gate voltage and controlling a slew rate of the second gate voltage.
    Type: Grant
    Filed: January 25, 2008
    Date of Patent: August 31, 2010
    Assignee: Marvell International Ltd.
    Inventors: Vishnu Mannoorittathu, Ying Tian Li
  • Patent number: 7786779
    Abstract: A buffer for a driving circuit includes a first transistor, a second transistor and a slew rate controlling circuit. The first transistor serves to provide a current to an output terminal. The second transistor serves to sink a current from the output terminal. The slew rate controlling circuit serves to control slew rate of at least one of the first transistor and the second transistor according to the input signal. The managing circuit serves to prevent the first transistor and the second transistor from turning on simultaneously.
    Type: Grant
    Filed: January 6, 2009
    Date of Patent: August 31, 2010
    Assignee: Himax Technologies Limited
    Inventors: Yaw-Guang Chang, Chin-Feng Hsu
  • Patent number: 7772901
    Abstract: A slew rate control circuit is disclosed. An output impedance buffer and a slew rate buffer are coupled in parallel. An edge detector detects an input signal to accordingly control the output impedance buffer and the slew rate buffer, such that the input signal passes through the slew rate buffer during a rising or falling time period, and the input signal only passes through the output impedance buffer during a stable time period, thereby conforming to specification requirements for the slew rate and the output impedance at the same time.
    Type: Grant
    Filed: January 8, 2009
    Date of Patent: August 10, 2010
    Assignee: Himax Technologies Limited
    Inventors: Yaw-Guang Chang, Lieh-Chiu Lin
  • Patent number: 7759994
    Abstract: In a skew signal generation circuit, a pad is connected to an external resistor and a code generator compares a voltage of the pad with a reference voltage to generate a plurality of codes. A skew signal extractor extracts a skew signal from the codes, the skew signal containing information about a current characteristic of a MOS transistor. A driver calibrates a drivability in response to the skew signal.
    Type: Grant
    Filed: December 27, 2007
    Date of Patent: July 20, 2010
    Assignee: Hynix Semiconductor Inc.
    Inventor: Ho Uk Song
  • Patent number: 7760006
    Abstract: Reducing electromagnetic radiation from semiconductor devices. At least some of the illustrative embodiments are methods comprising driving a Boolean state to a signal pad of a semiconductor device (the driving through a transistor with a first drain-to-source impedance during the driving), and maintaining the Boolean state applied to the signal pad through the transistor with a second drain-to-source impedance, higher than the first drain-to-source impedance.
    Type: Grant
    Filed: May 8, 2008
    Date of Patent: July 20, 2010
    Assignee: Texas Instruments Incorporated
    Inventors: Kevin P. Lavery, Jim D. Childers, Pravin P. Patel
  • Publication number: 20100176856
    Abstract: Disclosed is a circuit that adjusts a characteristic of a signal transmitted from a transmitter to a receiver over a communication channel (e.g., a wire, a backplane, etc.). The circuit includes a latch that receives the signal at a predetermined point in the circuit and samples a voltage of the signal many times after a threshold voltage is applied to the latch. The circuit also includes a processor that determines the characteristic of the signal when the sampled voltages indicate a transition point and that adjusts the threshold voltage when the sampled voltages do not indicate a transition point. The processor adjusts the characteristic of the signal by adjusting at least one of a current and a voltage of the transmitter when the characteristic of the signal is outside a predetermined range.
    Type: Application
    Filed: March 24, 2010
    Publication date: July 15, 2010
    Applicant: AGERE SYSTEMS INC.
    Inventors: Kouros Azimi, Mohammad S. Mobin, Gregory W. Sheets, Lane A. Smith
  • Publication number: 20100171538
    Abstract: A buffer for a driving circuit includes a first transistor, a second transistor and a slew rate controlling circuit. The first transistor serves to provide a current to an output terminal. The second transistor serves to sink a current from the output terminal. The slew rate controlling circuit serves to control slew rate of at least one of the first transistor and the second transistor according to the input signal. The managing circuit serves to prevent the first transistor and the second transistor from turning on simultaneously.
    Type: Application
    Filed: January 6, 2009
    Publication date: July 8, 2010
    Inventors: Yaw-Guang Chang, Chin-Feng Hsu
  • Publication number: 20100171539
    Abstract: A slew rate control circuit is disclosed. An output impedance buffer and a slew rate buffer are coupled in parallel. An edge detector detects an input signal to accordingly control the output impedance buffer and the slew rate buffer, such that the input signal passes through the slew rate buffer during a rising or falling time period, and the input signal only passes through the output impedance buffer during a stable time period, thereby conforming to specification requirements for the slew rate and the output impedance at the same time.
    Type: Application
    Filed: January 8, 2009
    Publication date: July 8, 2010
    Inventors: Yaw-Guang Chang, Lieh-Chiu Lin
  • Patent number: RE41926
    Abstract: The present invention discloses an output circuit that is able to adjust the output voltage slew rate and avoid short-circuit current, comprising: a control circuit for receiving an input data and generating a first set of control signals based on the input data; an output control device consisting of a first field effect transistor (FET) connected in series with a second field effect transistor (FET) and the point of connection is the output end for generating an output signal; a first capacitor having one end connected to a first working voltage and generates a first control voltage by charging/discharging on another end to control the gate of the first field effect transistor; a first switch for controlling charging/discharging of the first capacitor device based on the first set of control signals; a first current source for providing charging current for the first capacitor device; a second capacitor having one end connected to a second working voltage and generates a second control voltage by charging/d
    Type: Grant
    Filed: September 9, 2005
    Date of Patent: November 16, 2010
    Assignee: Realtek Semiconductor Corp.
    Inventor: An-Ming Lee