Source-coupled Logic (e.g., Current Mode Logic (cml), Differential Current Switch Logic (dcsl), Etc.) Patents (Class 326/115)
  • Publication number: 20100141296
    Abstract: A current mode logic voter circuit includes three two-input split NOR gates. Each two-input split NOR gate receives a corresponding pair of input signals and generates a pair of first output signals responsive to the input signals. A three input split NOR gate is coupled to the two-input split NOR gates to receive the first output signals and generates a second pair of output signals responsive to the first output signals from the two-input split NOR gates. The two and three-input split NOR gates can be formed from current mode logic buffer circuits, and in one embodiment in the three-input split NOR gate the buffer circuits are hardened.
    Type: Application
    Filed: December 10, 2008
    Publication date: June 10, 2010
    Applicant: BAE Systems Information and Electronics System Intergration, Inc.
    Inventors: Neil Wood, David Rea, Bin Li
  • Patent number: 7733128
    Abstract: To provide a transmitting apparatus capable of suppressing the fluctuation of a common mode potential and performing high-speed, long-distance signal transmission. The transmitting apparatus has a main buffer circuit and a pre-emphasis buffer circuit 20. The pre-emphasis buffer circuit 20, which has a switch circuit 21, a first current source 22, and a second current source 23, uses the switch circuit 21 to output a current signal having the same direction as an output current of the main buffer circuit 10 during a certain time interval starting from a time point when the level of data to be transmitted changes, and brings the output terminals 201, 202 to a High-Z state during a time interval when the level is constant after a lapse of the abovementioned certain time interval.
    Type: Grant
    Filed: April 25, 2006
    Date of Patent: June 8, 2010
    Assignee: Thine Electronics, Inc.
    Inventor: Satoshi Miura
  • Patent number: 7728630
    Abstract: A method and apparatus to reduce the degradation in performance of semiconductor-based devices due to process, voltage, and temperature (PVT) and/or other causes of variation. Adaptive feedback mechanisms are employed to sense and correct performance degradation, while simultaneously facilitating configurability within integrated circuits (ICs) such as programmable logic devices (PLDs). A voltage-feedback mechanism is employed to detect PVT variation and mirrored current references are adaptively adjusted to track and substantially eliminate the PVT variation. More than one voltage-feedback mechanism may instead be utilized to detect PVT-based variations within a differential device, whereby a first voltage-feedback mechanism is utilized to detect common-mode voltage variation and a second voltage-feedback mechanism produces mirrored reference currents to substantially remove the common-mode voltage variation and facilitate symmetrical operation of the differential device.
    Type: Grant
    Filed: January 29, 2009
    Date of Patent: June 1, 2010
    Assignee: XILINX, INC.
    Inventors: Guo Jun Ren, Qi Zhang, Ketan Sodha
  • Patent number: 7724037
    Abstract: The present disclosure relates to a differential signaling circuit including differential signaling circuitry having at least one output and one input, that can operate in multiple mode of operations while using a single, low voltage supply source. Two or more switches are included and configured to selectively couple a supply voltage to the output dependent on a mode of operation of the differential signaling circuitry. The circuit also includes a switch control biasing circuit operatively coupled to at least one of the switches and to the output of the differential signaling circuitry. The switch control biasing circuit provides a switch control biasing voltage to control a state of the switch based on a voltage level of the output. Further, a bulk biasing circuit is included and operatively coupled to the switch. The bulk biasing circuit selectively provides a bulk biasing voltage to the switch based on the voltage level of the output.
    Type: Grant
    Filed: January 13, 2009
    Date of Patent: May 25, 2010
    Assignee: ATI Technologies ULC
    Inventors: Junho Cho, Nancy Chan, Ramesh Senthinathan, Stephen Yue, Richard W. Fung
  • Patent number: 7710159
    Abstract: The invention relates to an electronic device that includes an MCML Muller-c element. The MCML Muller-c element has a first differential stage for operating in a trans-conductance state converting the differential input to a differential output current implementing the logical behavior of the MCML Muller-c element and a second stage operating as a trans-impedance stage being coupled to the first stage. Further, the MCML Muller-c element has peaking circuitry being coupled to the first stage, such that the peaking circuitry and the first stage provide a negative capacitance to the MCML Muller-c element for reducing the damping factor of the MCML Muller-c element.
    Type: Grant
    Filed: June 19, 2007
    Date of Patent: May 4, 2010
    Assignee: NXP B.V.
    Inventor: Suhas V. Shinde
  • Patent number: 7675326
    Abstract: Systems and methods are provided using dynamically adjustable differential output drivers. Integrated circuits such as programmable logic devices may be provided with adjustable differential output drivers for transmitting high-speed data to other integrated circuits. The peak-to-peak output voltage and common-mode voltage of the output drivers may be adjusted. Dynamic control circuitry may be used to control the settings of current sources, programmable resistors, and voltage source circuitry in the adjustable differential output driver automatically in real time. The adjustable components in the differential output driver may be adjusted by the dynamic control circuitry based on feedback information received from the integrated circuit to which the data is transmitted.
    Type: Grant
    Filed: June 27, 2008
    Date of Patent: March 9, 2010
    Assignee: Altera Corporation
    Inventors: Mei Luo, Sergey Shumarayev, Wilson Wong, Chong H. Lee
  • Patent number: 7656198
    Abstract: In one embodiment, an integrated device is disclosed. For example, in one embodiment of the present invention, a device comprises a logic control, and a combination differential driver coupled to the logic control, wherein the logic control receives a control signal for configuring the combination differential driver as a Low Voltage Differential Signaling (LVDS) driver or as a Transition Minimized Differential Signaling (TMDS) driver.
    Type: Grant
    Filed: December 3, 2007
    Date of Patent: February 2, 2010
    Assignee: Xilinx, Inc.
    Inventors: Shidong Zhou, Yi-hui Hsieh
  • Publication number: 20090302893
    Abstract: “Negative And” (NAND) logic gate metal oxide semiconductor field effect transistor (MOSFET) switch(es) are incorporated in the first stage of a “pseudo” current mode logic (CML) latch to provide a low-resistance (or high-resistance) circuit path to the output depending on the input voltage. These switch(es) are also used to deactivate (or “switch-off”) the first stage of the circuit during the second half of a timing clock cycle, so as to permit the first stage to be activated (or “switched-on”) only during the first half of a clock cycle. “Cross-coupled” inverter(s) are also used in the second stage of the circuit to provide acceptable “rail-to-rail” output voltage differential “swing” using less current.
    Type: Application
    Filed: June 5, 2008
    Publication date: December 10, 2009
    Inventor: Sarabjeet Singh
  • Publication number: 20090302887
    Abstract: A programmable logic device (PLD) includes a driver circuit, a configuration memory, and a control circuit. The configuration memory stores driver strength information for the driver circuit. The control circuit uses the driver strength information stored in the configuration circuit to control the driver strength of the driver.
    Type: Application
    Filed: September 23, 2008
    Publication date: December 10, 2009
    Inventors: Tad Kwasniewski, Rakesh H. Patel
  • Publication number: 20090273370
    Abstract: The invention relates to an electronic device that includes an MCML Muller-c element. The MCML Muller-c element has a first differential stage for operating in a trans-conductance state converting the differential input to a differential output current implementing the logical behavior of the MCML Muller-c element and a second stage operating as a trans-impedance stage being coupled to the first stage. Further, the MCML Muller-c element has peaking circuitry being coupled to the first stage, such that the peaking circuitry and the first stage provide a negative capacitance to the MCML Muller-c element for reducing the damping factor of the MCML Muller-c element.
    Type: Application
    Filed: June 19, 2007
    Publication date: November 5, 2009
    Applicant: NXP B.V.
    Inventor: Suhas V. Shinde
  • Patent number: 7609084
    Abstract: An output level stabilization circuit being an output level stabilization circuit for a CML circuit, the output level stabilization circuit includes: a replica circuit constituted of transistors respectively having the same characteristics as one of differential-pair transistors of the CML circuit and a current source transistor; a comparison circuit which compares an output of the replica circuit with a reference voltage and supplies the comparison result as a control voltage for the current source transistor of the replica circuit; and a variable impedance circuit arranged between the output of the replica circuit and an input of the comparison circuit.
    Type: Grant
    Filed: February 15, 2008
    Date of Patent: October 27, 2009
    Assignee: NEC Corporation
    Inventor: Yusuke Matsushima
  • Patent number: 7605613
    Abstract: A current switch logic circuit is disclosed. The circuit includes a current sense amplifier formed by a first transistor to a fifth transistor, and a logic tree. The logic tree is used to generate a first current and a second current. The current sense amplifier generates a first output signal and a second output signal according to the first current and the second current.
    Type: Grant
    Filed: June 18, 2008
    Date of Patent: October 20, 2009
    Assignee: Industrial Technology Research Institute
    Inventors: Hong-Yi Huang, Chun-Tsai Hung, Yuan-Hua Chu
  • Patent number: 7605614
    Abstract: A current switch logic circuit is disclosed. The circuit includes a current sense amplifier formed by a first transistor to a fifth transistor, and a logic tree. The logic tree is used to generate a first current and a second current. The current sense amplifier generates a first output signal and a second output signal according to the first current and the second current.
    Type: Grant
    Filed: June 18, 2008
    Date of Patent: October 20, 2009
    Assignee: Industrial Technology Research Institute
    Inventors: Hong-Yi Huang, Chun-Tsai Hung, Yuan-Hua Chu
  • Patent number: 7595662
    Abstract: A transmission device transmits differential signals that are to be output, in the form of current signals via first and second output terminals. A first switching transistor and a first output transistor are serially connected between the grounded terminal, which is set to a fixed electric potential, and the first output terminal. A second switching transistor and a second output transistor are serially connected between the grounded terminal and the second output terminal. First and second bias transistors are provided in parallel with the first and second switching transistors, and generate a predetermined bias current. A pair of differential signals, which are to be transmitted, are input to the gates of the first and second switching transistors. The gates of the first and second output transistors are biased at a predetermined first voltage.
    Type: Grant
    Filed: July 19, 2007
    Date of Patent: September 29, 2009
    Assignee: Rohm Co., Ltd.
    Inventor: Shinichi Saito
  • Publication number: 20090219054
    Abstract: A digital circuit comprises: a first arm including a first metal oxide semiconductor field effect transistor (M3) configured to act as a load device; a second arm including a second metal oxide semiconductor field effect transistor (M4) configured to act as a load device; and a switch (M1, M2) for selecting one of the first and second arms. Each of the first and second transistors (M3, M4) has a channel length of 100 nm or below and is biased to operate in the weak inversion regime. In an alternative circuit, each load device (M3, M4) has its bulk connected to its drain and is biased to operate in the weak inversion regime.
    Type: Application
    Filed: October 27, 2006
    Publication date: September 3, 2009
    Inventors: Christofer Toumazou, Francesco Cannillo
  • Publication number: 20090212821
    Abstract: A current switch logic circuit is disclosed. The circuit includes a current sense amplifier formed bit a first transistor to a fifth transistor, and a logic tree. The logic tree is used to generate a first current and a second current. The current sense amplifier generates a first output signal and a second output signal according to the first current and the second current.
    Type: Application
    Filed: June 18, 2008
    Publication date: August 27, 2009
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Hong-Yi Huang, Chun-Tsai Hung, Yuan-Hua Chu
  • Publication number: 20090212822
    Abstract: A current switch logic circuit is disclosed. The circuit includes a current sense amplifier formed by a first transistor to a fifth transistor, and a logic tree. The logic tree is used to generate a first current and a second current. The current sense amplifier generates a first output signal and a second output signal according to the first current and the second current.
    Type: Application
    Filed: June 18, 2008
    Publication date: August 27, 2009
    Applicant: INDUSTRIAL TECHNOLOGY RESEARCH INSTITUTE
    Inventors: Hong-Yi Huang, Chun-Tsai Hung, Yuan-Hua Chu
  • Publication number: 20090212823
    Abstract: The present invention provides a low jitter CMOS to CML converter, including: a differential circuit including differential pair transistors, a pair of loads and a biased transistor, each differential transistor of the differential pair transistors having an input terminal, an output terminal and a connection terminal. With the current compensation device, an additional current path may be provided for the current of the biased transistor which is used as a constant current source when the differential transistors are turned off, so that the peak tail current in the biased transistor current may be eliminated. Thus, the problem caused by the tail current that the common mode output voltages of the converter is unstable and has a high jitter may be solved.
    Type: Application
    Filed: February 23, 2009
    Publication date: August 27, 2009
    Applicant: Semiconductor Manufacturing International (Shanghai) Corporation
    Inventors: Qianyu Yu, Josh Chiachi Yang, Hao Liu
  • Patent number: 7579872
    Abstract: A low-voltage differential signal driver for high-speed digital transmission includes a first converter operable to receive a signal in a first type and convert the signal into a second type, wherein a resistance of the first converter is variable. A second converter couples to the first converter, the second converter is operable to receive a signal in the second type and convert the signal into the first type, wherein a resistance of the second converter is variable. The driver is operable to scale the resistance of the first and second converters to provide a constant ratio between the resistance of the first and second converters.
    Type: Grant
    Filed: May 31, 2006
    Date of Patent: August 25, 2009
    Assignee: Fujitsu Limited
    Inventor: Jian Hong Jiang
  • Patent number: 7576567
    Abstract: A low-voltage differential signal driver for high-speed digital transmission includes a first converter operable to receive a signal in a first type and convert the signal into a second type, and a cascode current mirror coupled to the first converter. The cascode current mirror provides an impedance level that increases a differential output voltage.
    Type: Grant
    Filed: May 31, 2006
    Date of Patent: August 18, 2009
    Assignee: Fujitsu Limited
    Inventor: Jian Hong Jiang
  • Patent number: 7564268
    Abstract: A low power logic output buffer includes first and second logic gates, each having an input and an output. The input of the first logic gate receives a first logic signal, and the input of the second logic gate receives a second logic signal. The buffer includes first, second, third and fourth n-type metal oxide semiconductor (NMOS). The buffer also includes first and second bias switching NMOS. The first bias switching NMOS is coupled between the source of the third NMOS and ground, and the gate of the first bias switching NMOS is coupled to the output of the first logic gate. The second bias switching NMOS is electrically coupled between the source of the fourth NMOS and ground, and the gate of the second bias switching NMOS is coupled to the output of the second logic gate.
    Type: Grant
    Filed: November 7, 2006
    Date of Patent: July 21, 2009
    Assignee: Integrated Device Technology, inc
    Inventor: Brian J. Buell
  • Patent number: 7564270
    Abstract: A driver circuit is provided herein. In general, the driver circuit includes a driver portion, a common mode feedback portion and a current replication portion. The feedback portion receives a common mode voltage (vcm) from the driver portion and an alternative common mode voltage (vcm_alt) from the current replication portion. The feedback portion selects one of the common mode voltages for comparison with a reference voltage and generates a feedback bias signal (vcmfb) based on a voltage difference there between. When the driver circuit is enabled, the actual common mode voltage (vcm) is used to maintain the output common mode voltage around the reference voltage. When the driver circuit is disabled, the alternative common mode voltage (vcm_alt) is used to keep the bias signal (vcmfb) from drifting away.
    Type: Grant
    Filed: June 27, 2007
    Date of Patent: July 21, 2009
    Assignee: Cypress Semiconductor Corporation
    Inventors: Xiaohu Zhang, George Ansel
  • Patent number: 7560957
    Abstract: A current mode logic digital circuit is provided comprising a logic circuit component having at least one data input node and at least one output node. A load is coupled between a power supply node and the output node. The load comprises a folded active inductor coupled to the output node.
    Type: Grant
    Filed: June 1, 2006
    Date of Patent: July 14, 2009
    Assignee: Agere Systems Inc.
    Inventors: Jinghong Chen, Gregory W. Sheets, Lane A. Smith
  • Publication number: 20090140771
    Abstract: Various circuit techniques for implementing ultra high speed circuits use current-controlled CMOS (C3MOS) logic with inductive broadbanding fabricated in conventional CMOS process technology. Optimum balance between power consumption and speed for each circuit application is achieved by combining high speed C3MOS logic with inductive broadbanding/C3MOS logic with low power conventional CMOS logic. The combined C3MOS logic with inductive broadbanding/C3MOS/CMOS logic allows greater integration of circuits such as high speed transceivers used in fiber optic communication systems.
    Type: Application
    Filed: February 10, 2009
    Publication date: June 4, 2009
    Applicant: BROADCOM CORPORATION
    Inventor: Michael M. Green
  • Patent number: 7532037
    Abstract: A method for enhancing a CML driver circuit to allow efficient, and accurate measurement of the magnitude of the voltage domain noise present near a CML driver in an integrated circuit. The disclosed method for enhancing a CML driver circuit to enable quiet driver measurement includes providing a predetermined low impedance path from the power rail of said CML driver circuit via a first node to the output pins of the circuit and providing a predetermined low impedance path from the ground rail of said CML driver circuit via a second node to the output pins of the circuit. The method also includes disabling the current source causing the pull-up termination circuitry to become high impedance, and the logic driving said inputs of the CML circuit to exist in a low state and performing a low impedance measurement of the power rail noise, ground rail noise and the chip noise in the region of the CML driver.
    Type: Grant
    Filed: May 5, 2008
    Date of Patent: May 12, 2009
    Assignee: International Business Machines Corporation
    Inventors: Axel Aguado Granados, Benjamin Aaron Fox, Nathaniel James Gibbs, Andrew Benson Maki, Trevor Joseph Timpane
  • Publication number: 20090115457
    Abstract: The present disclosure relates to a differential signaling circuit including differential signaling circuitry having at least one output and one input, that can operate in multiple mode of operations while using a single, low voltage supply source. Two or more switches are included and configured to selectively couple a supply voltage to the output dependent on a mode of operation of the differential signaling circuitry. The circuit also includes a switch control biasing circuit operatively coupled to at least one of the switches and to the output of the differential signaling circuitry. The switch control biasing circuit provides a switch control biasing voltage to control a state of the switch based on a voltage level of the output. Further, a bulk biasing circuit is included and operatively coupled to the switch. The bulk biasing circuit selectively provides a bulk biasing voltage to the switch based on the voltage level of the output.
    Type: Application
    Filed: January 13, 2009
    Publication date: May 7, 2009
    Applicant: ATI Technologies ULC
    Inventors: Junho Cho, Nancy Chan, Ramesh Senthinathan, Stephen Yue, Richard W. Fung
  • Patent number: 7521964
    Abstract: In level-shifting circuitry for shifting low-voltage-domain signals to a high-voltage domain, one of two output transistors is driven with one of the low-voltage-domain signals, thereby reducing loading on the output and increasing output speed and bandwidth. The circuitry can be mirrored for differential operation. When included in a serial interface of a programmable logic device, the circuitry can be programmably selectable between single-ended and differential operation.
    Type: Grant
    Filed: March 26, 2007
    Date of Patent: April 21, 2009
    Assignee: Altera Corporation
    Inventors: Mei Luo, Vinh Van Ho
  • Patent number: 7514969
    Abstract: A conventional driver circuit has difficulty in controlling output voltages such as an output amplitude and a middle voltage in a CML circuit. Furthermore, in another conventional driver circuit, a high level of an output voltage in the CML circuit is dropped from a power supply voltage. To solve these problems, disclosed is a driver circuit including: an amplitude converter which converts the amplitude of a differential output signal and outputs a differential output signal; an amplitude setting unit which sets the amplitude of the differential output signal; and a common voltage setting unit which sets a center potential of the amplitude of the differential output signal.
    Type: Grant
    Filed: August 2, 2007
    Date of Patent: April 7, 2009
    Assignee: NEC Electronics Corporation
    Inventor: Masashi Nakagawa
  • Patent number: 7501860
    Abstract: A differential input driver circuit (10, 50) includes first and second transistors (Q0, Q3) as input transistors and third and fourth transistors (Q1, Q2) as diode-connected, cross-coupled transistors. In one embodiment, first, second, third and fourth transistors are NPN bipolar transistors. The base terminals of the first and third transistors are connected while the base terminals of the second and fourth transistors are connected. The input transistors receive a pair of differential input signals (In+/?) at the emitter terminals (24, 26) and provides a pair of differential output signals (Vo+/?) at the collector terminals (16, 18). The emitter terminals of the diode-connected transistors (Q1, Q2) couple the input signal at the emitter terminal of the first transistor to the collector terminal of the second transistor and vice versa. The cross-coupling of the third and fourth transistors enables the input driver to operate effectively in single-ended to differential conversion mode.
    Type: Grant
    Filed: December 3, 2007
    Date of Patent: March 10, 2009
    Assignee: National Semiconductor Corporation
    Inventors: Andrew Fitting, Michael Maida
  • Publication number: 20090058464
    Abstract: A current mode logic (CML)-complementary metal oxide semiconductor (CMOS) converter prevents change of a duty ratio to stably operate during an operation for converting a CML level signal into a CMOS level signal. The CML-CMOS converter includes a reference level shifting unit configured to receive a CML signal swinging about a first reference level to shift a swing reference level to a second reference level; and an amplifying unit configured to amplify an output signal of the reference level shifting unit to output the amplified signal as a CMOS signal.
    Type: Application
    Filed: December 26, 2007
    Publication date: March 5, 2009
    Inventors: Kyung-Hoon Kim, Dae-Han Kwon
  • Patent number: 7498843
    Abstract: Various circuit techniques for implementing ultra high speed circuits use current-controlled CMOS (C3MOS) logic with inductive broadbanding fabricated in conventional CMOS process technology. Optimum balance between power consumption and speed for each circuit application is achieved by combining high speed C3MOS logic with inductive broadbanding/C3MOS logic with low power conventional CMOS logic. The combined C3MOS logic with inductive broadbanding/C3MOS/CMOS logic allows greater integration of circuits such as high speed transceivers used in fiber optic communication systems.
    Type: Grant
    Filed: January 31, 2006
    Date of Patent: March 3, 2009
    Assignee: Broadcom Corporation
    Inventor: Michael M. Green
  • Patent number: 7495477
    Abstract: The present disclosure relates to a differential signaling circuit including differential signaling circuitry having at least one output and one input, that can operate in multiple mode of operations while using a single, low voltage supply source. Two or more switches are included and configured to selectively couple a supply voltage to the output dependent on a mode of operation of the differential signaling circuitry. The circuit also includes a switch control biasing circuit operatively coupled to at least one of the switches and to the output of the differential signaling circuitry. The switch control biasing circuit provides a switch control biasing voltage to control a state of the switch based on a voltage level of the output. Further, a bulk biasing circuit is included and operatively coupled to the switch. The bulk biasing circuit selectively provides a bulk biasing voltage to the switch based on the voltage level of the output.
    Type: Grant
    Filed: July 31, 2007
    Date of Patent: February 24, 2009
    Assignee: ATI Technologies, Inc.
    Inventors: Junho Cho, Nancy Chan, Ramesh Senthinathan, Stephen Yue, Richard W. Fung
  • Patent number: 7486103
    Abstract: A switching system capable of reducing the noise of the output signal is provided. The switching system includes a first switch and a second switch, wherein the first switch conducts a first signal according to a first control signal; the second switch conducts a second signal according to a second control signal. And the voltages of the first control signal and the second control signal are restricted within a voltage interval to reduce the noise produced during the switching of the switches.
    Type: Grant
    Filed: April 12, 2007
    Date of Patent: February 3, 2009
    Assignee: Young Lighting Technology Corporation
    Inventors: Shian-Sung Shiu, Chung-Che Yu, Kuo-Wei Peng
  • Patent number: 7474127
    Abstract: According to one embodiment of the invention, a method for receiving a first signal in a first plurality of switching elements from a second plurality of switching elements, receiving a second signal in second plurality of switching elements from first plurality of switching elements, alternatively converting a first logic signal by first plurality of switching elements based on received first signal, and a second logic signal by the second plurality of switching elements based on received second signal. According to another embodiment of the invention, a system comprising a first plurality of switching elements to convert a first logic signal based on a predetermined input from a second plurality of switching elements, second plurality of switching elements to convert a second logic signal based on a predetermined input received from first plurality of switching elements; first and second plurality of switching elements to alternatively convert first and second logic signals.
    Type: Grant
    Filed: January 6, 2006
    Date of Patent: January 6, 2009
    Assignee: Intel Corporation
    Inventor: Ravindran Mohanavelu
  • Patent number: 7463068
    Abstract: A circuit for protection of a transceiver input includes an input transistor and a first resistor connected between the drain of the input transistor and an input node. A plurality of reverse-biased diodes connected between a supply voltage and the input node. An output node is connected to the source of the input transistor. A first forward-biased diode connected between the power supply and the plurality of reverse-biased transistors. A second forward-biased diode and a second resistor are connected between the first forward biased transistor and the gate of the input transistor. A pre-driver circuit includes first and second transistors forming a differential pair and driven by a differential input voltage. A third transistor is connected between sources of the first and second transistors and ground. First and second resistors are connected to drains of the first and second transistors, respectively. A fourth transistor is connected between a power supply voltage and the first and second resistors.
    Type: Grant
    Filed: March 2, 2007
    Date of Patent: December 9, 2008
    Assignee: Broadcom Corporation
    Inventors: Wee Teck Lee, Tu Yun, Tian Hwee Teo
  • Patent number: 7446572
    Abstract: A method and system for a configurable Vcc reference and Vss reference differential current mode transmitter is described. The system includes a Vss reference differential current mode driver, a Vcc reference differential current mode driver coupled to the Vss reference current mode driver, and a controller circuit coupled to the Vss reference differential current mode driver and the Vcc reference differential current mode driver to select between the Vss reference differential current mode driver and the Vcc reference differential current mode driver based on a type of transmission interface.
    Type: Grant
    Filed: June 27, 2005
    Date of Patent: November 4, 2008
    Assignee: Intel Corporation
    Inventors: Hing Y. To, James A. McCall, Michael Sandhinti
  • Patent number: 7439773
    Abstract: An semiconductor device, containing logic blocks and high speed connections between the blocks, where the connections utilize current direction for logic representation rather than voltage level. Such high speed connections comprise differential transmitters which drive a pair of adjacent wires with differential current pulses that are received by a differential receiver which may be put in a low power state between transmissions.
    Type: Grant
    Filed: October 11, 2005
    Date of Patent: October 21, 2008
    Assignee: cASIC Corporation
    Inventors: Zvi Or-Bach, Adrian Apostol, Laurence H. Cooke
  • Patent number: 7432741
    Abstract: Transmitter driver circuitry includes multiple output driver stages, each of which receives a respective differently-phased version of an output signal for application to an output node of the circuitry. Each stage includes a primary current source. The circuitry also includes at least one secondary current source. The secondary current source can be used to supply supplementary current to the output node to eliminate or at least substantially reduce offset at the output node.
    Type: Grant
    Filed: December 18, 2006
    Date of Patent: October 7, 2008
    Assignee: Altera Corporation
    Inventor: Sergey Shumarayev
  • Patent number: 7429874
    Abstract: Provided is a replica bias circuit which is suitable for multi-layer stacked CMOS current mode logic (CML) and is stably used in application fields using a low power supply voltage. The replica bias circuit applies a reference voltage to gates of target transistors constituting an electronic circuit. The replica bias circuit includes a sub threshold voltage generator for maintaining a voltage difference lower than a threshold voltage of the transistor; and a replica path including devices designed by referring to dimensions of constituent devices forming a current flow path, the current flow path including the target transistors in the electronic circuit. With the replica bias circuit, multi-layer stacked CMOS current mode logic (CML) circuits can stably operate even at a low power supply voltage.
    Type: Grant
    Filed: June 13, 2006
    Date of Patent: September 30, 2008
    Assignee: Electronics and Telecommunications Research Institute
    Inventors: Sang Jin Byun, Hyun Kyu Yu
  • Patent number: 7425847
    Abstract: A method and circuit of a biased input buffer is described to maximize the quality in the output signals. The input buffer includes a first stage for receiving differential input signals and generating differential internal signals as biased in response to an averaging of the differential internal signals. The input buffer further includes a second stage coupled to the differential internal signals and configured to generate differential output signals. A memory device includes a memory array with the respective input buffer. Differential input signals are received and differential internal signals are generated as biased in response to an averaging of the differential internal signals. Differential output signals are generated in a second stage from the differential internal signals.
    Type: Grant
    Filed: February 3, 2006
    Date of Patent: September 16, 2008
    Assignee: Micron Technology, Inc.
    Inventor: Dragos Dimitriu
  • Patent number: 7408385
    Abstract: A receiver circuit, which is connected with a partner transmitter circuit through a signal line and receives a signal based on current which flows through the signal line, includes a current/voltage conversion circuit which converts the current which flows through the signal line into voltage, a power supply circuit which adjusts the current which flows through the signal line based on a bias voltage Vb and voltage of a node NDX connected with the signal line, and a bias voltage generation circuit which outputs the bias voltage Vb which is adjusted in connection with characteristics of the power supply circuit.
    Type: Grant
    Filed: May 1, 2006
    Date of Patent: August 5, 2008
    Assignee: Seiko Epson Corporation
    Inventor: Makoto Takamuku
  • Patent number: 7405600
    Abstract: A current mode logic (CML)-CMOS converter comprises an input stage that is turned on/off by receiving an input voltage from the outside; a voltage control unit that outputs a constant voltage; a first switching unit that is connected to the input stage and the voltage control unit and is turned on/off by the constant voltage applied from the voltage control unit; and a second switching unit that is connected to the input stage and is turned on/off by a signal applied from the input stage.
    Type: Grant
    Filed: July 31, 2007
    Date of Patent: July 29, 2008
    Assignee: Samsung Electro-Mechanics Co., Ltd.
    Inventors: Yu Sin Kim, Jeong Ho Moon, Moo Il Jeong, Chang Seok Lee, Chang Soo Yang, Sang Gyu Park, Kwang Du Lee
  • Patent number: 7400170
    Abstract: A differential current-mode driver that meets the IEEE 1394 standard employs a wide output range in common-mode voltage, minimizes timing skew over this wide range, and has well-controlled rise/fall times in the edge rates of the digital signals transmitted, within the window specified by the IEEE 1394 standard, without having to resort to full-swing (VDD to VSS) gate drive signals. In a preferred embodiment PMOS and NPOS transistors are used to provide current for a current driver, in the form of a current steering switch switching a pair of current mirrors. The current mirrors output is input to a predriver waveform circuit which divides current between a data source A and data source B, forming the differential signal pair. Certain key transistors in the current driver are kept in saturation to improve performance.
    Type: Grant
    Filed: April 28, 2006
    Date of Patent: July 15, 2008
    Assignee: LSI Logic Corporation
    Inventor: Rick Bitting
  • Patent number: 7400173
    Abstract: A transmission system, circuit and method are provided herein for converting differential signals into low duty cycle distortion, single-ended signals that are insensitive to variations in PVT and input common mode voltage. In one embodiment, the signal translation circuit includes an input stage for receiving a pair of differential input signals and producing one or more differential output signals; an intermediate stage for combining the one or more differential output signals into a pair of complementary signals from which a common mode voltage is detected; and an output stage for generating a single-ended output signal that switches from a first value to an opposite value when one of the complementary signals is substantially equal to the common mode voltage.
    Type: Grant
    Filed: August 20, 2004
    Date of Patent: July 15, 2008
    Assignee: Cypress Semicondductor Corp.
    Inventors: David K. Kwong, Kuo-Chi Chien
  • Patent number: 7400169
    Abstract: According to one exemplary embodiment, an inductor-tuned buffer circuit includes at least one input transistor for receiving a time varying input signal, where the at least one input transistor drives an output of the buffer circuit. The buffer circuit further includes a buffer inductor coupled to the output of the buffer circuit. The buffer circuit is utilized to drive a capacitive load through an interconnecting conductor, where the buffer inductor is situated in proximity to the capacitive load so as to cause a parasitic inductance of the interconnecting conductor to be less than, or much less than, the buffer inductor.
    Type: Grant
    Filed: August 22, 2006
    Date of Patent: July 15, 2008
    Assignee: Broadcom Corporation
    Inventor: Bo Zhang
  • Patent number: 7397283
    Abstract: A circuit includes a configurable receiver circuit, a multiplexer or demultiplexer coupled to the configurable receiver circuit, and a configurable driver circuit coupled to the multiplexer or demultiplexer. The configurable receiver circuit generates an internal format signal which is received by the multiplexer or demultiplexer. The configurable driver circuit receives the internal format signal from the multiplexer or demultiplexer.
    Type: Grant
    Filed: September 29, 2006
    Date of Patent: July 8, 2008
    Assignee: Parade Technologies, Ltd.
    Inventors: Jimmy Chiu, Ming Qu, Ji Zhao
  • Patent number: 7397270
    Abstract: Systems and methods are provided using dynamically adjustable differential output drivers. Integrated circuits such as programmable logic devices may be provided with adjustable differential output drivers for transmitting high-speed data to other integrated circuits. The peak-to-peak output voltage and common-mode voltage of the output drivers may be adjusted. Dynamic control circuitry may be used to control the settings of current sources, programmable resistors, and voltage source circuitry in the adjustable differential output driver automatically in real time. The adjustable components in the differential output driver may be adjusted by the dynamic control circuitry based on feedback information received from the integrated circuit to which the data is transmitted.
    Type: Grant
    Filed: May 25, 2005
    Date of Patent: July 8, 2008
    Assignee: Altera Corporation
    Inventors: Mei Luo, Sergey Shumarayev, Wilson Wong, Chong H. Lee
  • Patent number: 7394283
    Abstract: A signal regenerator is provided which includes a common mode reference generator and a signal converter circuit. A common mode reference voltage level is generated which is variable in relation to at least one of a process used to fabricate the common mode reference generator, a level of a power supply voltage provided to the common mode reference generator or a temperature at which the common mode reference generator is operated. A signal converter circuit receives a differentially transmitted signal pair including a first input signal and a second input signal and outputs a single-ended output signal representing information carried by the differentially transmitted signal pair. Using a feedback signal from the common mode reference generator, a feedback control block controls a common mode level of the single-ended output signal in accordance with the common mode reference voltage level.
    Type: Grant
    Filed: August 25, 2006
    Date of Patent: July 1, 2008
    Assignee: International Business Machines Corporation
    Inventors: Louis L. Hsu, Gautam Gangasani, Michael A. Sorna, Steven J. Zier
  • Publication number: 20080150584
    Abstract: Disclosed herein is a CML circuit that can solve a conventional problem that it has been impossible to input a large amplitude signal to a differential pair.
    Type: Application
    Filed: November 7, 2007
    Publication date: June 26, 2008
    Applicant: NEC ELECTRONICS CORPORATION
    Inventor: Makoto TANAKA
  • Patent number: 7388406
    Abstract: A CML digital circuit includes a load coupled between a power supply node and at least one output node and a logic circuit component coupled to the output node. The logic circuit component has at least one data input node. The logic circuit component comprises a first circuit module and a second circuit module. A first tail current source is coupled to the first circuit module. A second tail current source is coupled to the second circuit module. A first switch is coupled between the power supply node and the first tail current source. A second switch is coupled between the power supply node and the second tail current source, wherein the first switch is triggered to deactivate the first circuit module when the second circuit module is operating and the second switch is triggered to deactivate the second circuit module when the first circuit module is operating.
    Type: Grant
    Filed: May 24, 2006
    Date of Patent: June 17, 2008
    Assignee: Agere Systems Inc.
    Inventor: Jinghong Chen