Differential Input Patents (Class 327/65)
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Patent number: 6919652Abstract: A network apparatus is provided, which allows another network apparatus to recognize the disconnection with reliability, if a power supply to the network apparatus is interrupted. A control unit operating with a first power supply outputs a first signal, which is level-converted and supplied as a second signal to an intermediate potential supply unit operating with a second power supply. In the intermediate potential supply unit, a switch receives a reset signal as a switch signal and outputs, when the power supply is interrupted, a ground potential to a driver instead of the second signal. As a result, an intermediate potential supplied to a cable is forcibly set to the ground potential.Type: GrantFiled: January 4, 2002Date of Patent: July 19, 2005Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Satoshi Takahashi, Takashi Hirata, Hironori Akamatsu, Yoshihide Komatsu, Koichi Sugimoto
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Patent number: 6914455Abstract: A signal amplitude limiting circuit includes a differential circuit, a feed back circuit and a voltage supply circuit. The differential circuit has a positive input terminal, a negative input terminal, a positive output terminal and a negative output terminal. The feedback circuit is connected to the differential circuit. The feedback circuit compares voltages at the positive and negative output terminals with a reference voltage and outputs a comparison signal in response to the comparison. The voltage supply circuit is connected to the differential circuit and the feedback circuit. The voltage supply circuit provides a current to the differential circuit in response to the comparison signal.Type: GrantFiled: January 13, 2003Date of Patent: July 5, 2005Assignee: Oki Electric Industry Co., Ltd.Inventors: Yoshikazu Yoshida, Akira Horikawa
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Patent number: 6909310Abstract: A line driver fabricated from CMOS devices that provides a substantially constant output impedance over a significant range of a time-varying input voltage includes a time-varying current source, a pair of CMOS output loads, and a pair of biasing circuits. Each CMOS output load includes a NMOS transistor and a PMOS transistor connected in parallel and each biased into a linear range of operation. In response to a time-varying input voltage, the time-varying current source draws current from the pair of CMOS output loads in a manner that operates each CMOS output load to collectively establish a time-varying output voltage component at an associated output terminal.Type: GrantFiled: January 30, 2003Date of Patent: June 21, 2005Assignee: Agilent Technologies, Inc.Inventors: Kenneth D. Poulton, Robert M. R. Neff, Jorge A. Pernillo, Mehrdad Heshami
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Patent number: 6900686Abstract: An analog switching circuit selects one of a first pair of differential outputs of a first circuit having a first common mode voltage and a second pair of differential outputs of a second circuit having a second common mode voltage. The analog switching circuit includes first and second switches having one of a source and drain that communicate with the first pair of differential outputs. Third and fourth switches have one of a source and drain that communicate with the second pair of differential outputs. An operational amplifier has a first input that communicates with the other of the source and drain of the first and third switches and a second input that communicates with the other of the source and drain of the second and fourth switches. A common mode feedback circuit communicates with the first and second inputs of the operational amplifier and maintains a common mode voltage input of the amplifier below the first and second common mode voltages.Type: GrantFiled: June 5, 2003Date of Patent: May 31, 2005Assignee: Marvell International Ltd.Inventor: Pierte Roo
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Patent number: 6891405Abstract: The present invention provides systems and methods related to a variable gain amplifier. The variable gain amplifier includes a first differential amplifier, a second differential amplifier, a combining circuit, and a current control circuit. The first differential amplifier circuit and the second differential amplifier circuit share a common input signal and have different amplification degrees. Each of the first and second differential amplifier circuits includes a first transistor and a second transistor that form a differential pair. The first transistor and the second transistor of each differential amplifier circuit have bases that are supplied with the input signal, and collectors that output signals to the combining circuit. The current control circuit changes a ratio between a bias current of the first differential amplifier circuit and a bias current of said second differential amplifier circuit based on a gain control signal.Type: GrantFiled: July 10, 2002Date of Patent: May 10, 2005Assignee: Sony CorporationInventors: Kazuhiro Fujimura, Shinichi Tanabe
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Patent number: 6888444Abstract: In transmitting a first pair of differential clock signals UCLK, UXCLK having an extremely small amplitude voltage based on a power-source potential and a second pair of differential clock signals LCLK, LXCLK having an extremely small amplitude voltage based on the power-source potential, an inverting circuit as a signal receiving circuit is composed of a CMOS inverting circuit. A PMOS transistor composing the CMOS inverting circuit has a gate electrode and a source electrode receiving the first pair of differential clock signals. An NMOS transistor composing the CMOS inverting circuit has a gate electrode and a source electrode receiving the second pair of differential clock signals. When the potentials of the differential clock signals change, potentials at the respective gate and source electrodes of the two transistors shift in opposite directions, which surely cuts off the transistors.Type: GrantFiled: January 19, 1999Date of Patent: May 3, 2005Assignee: Matsushita Electric Industrial Co., Ltd.Inventor: Hiroyuki Yamauchi
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Patent number: 6870404Abstract: Programmable differential capacitance is implemented in equalization circuits. The programmable differential capacitance improves the common mode rejection ratio of circuits processing differential signals of various frequencies and voltage swings. Multiple capacitance devices provide the programmable capacitance, which provides an equalization circuit with different, selectable (i.e., programmable) values of capacitance for boosting the transition speed and strength of differential signals processed by the equalization circuit.Type: GrantFiled: August 28, 2003Date of Patent: March 22, 2005Assignee: Altera CorporationInventor: Simar Maangat
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Patent number: 6867621Abstract: A differential line driver includes first, second, third and fourth cascode transistors connected in parallel, wherein drains of the first and third transistors are connected to a negative output of the differential line driver, and wherein drains of the second and fourth transistors are connected to a positive output of the differential line driver. First, second, third and fourth switching transistors are connected in series with corresponding first, second, third and fourth cascode transistors and driven by a data signal. First and second compound transistors inputting a class AB operation signal at their gates, wherein the first compound transistor is connected to sources of the first and second switching transistors, and wherein the second compound transistor is connected to sources of the third and fourth switching transistors.Type: GrantFiled: November 25, 2003Date of Patent: March 15, 2005Assignee: Broadcom CorporationInventors: Jan Mulder, Yee Ling Cheung
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Patent number: 6856158Abstract: A comparator circuit for use in a semiconductor test system for comparing differential output signals of a semiconductor device under test (DUT). The comparator circuit is formed of a first pair of comparators having a DC comparator and an AC comparator which receives a first differential signal, a second pair of comparators having a DC comparator and an AC comparator which receives a second differential signal, a first latch for latching output of the first pair of comparators, a second latch for latching output of the second pair of comparators, and first and second serial-parallel converters for converting output signals of the first and second latches into parallel signals. The comparator circuit is formed of discrete components on a dielectric substrate.Type: GrantFiled: May 1, 2002Date of Patent: February 15, 2005Assignee: Advantest Corp.Inventors: James W. Frame, Richard W. Chrusciel
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Patent number: 6847234Abstract: The present invention provide an CMOS comparator outputting one bit digital signal after comparing two analog input signals through alternately performing a track mode operation and latch mode operation decided by a clock signal having a constant period, including: a latching unit having the main/sub input terminal; a first switching transistor having the clock signal as a gate input and having one end coupled to main input terminal; a first load transistor diode-connected to the other end of the first switching transistor and a ground end; a second switching transistor having a gate receiving the clock signal as a gate input and one end coupled to the sub input terminal; and a second load transistor diode-connected to the second switching transistor and to the other end of the ground terminal.Type: GrantFiled: July 14, 2003Date of Patent: January 25, 2005Assignee: Hynix Semiconductor Inc.Inventor: Soo-Chang Choi
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Publication number: 20040263214Abstract: An apparatus comprising a first differential output driver to provide a single ended output voltage in response to an input voltage, a second differential output driver to provide a single ended output in response to the input voltage where the first output voltage and the second output voltage are representative of the positive and inverted input voltage. The apparatus also includes a feedback circuit to monitor the first and second output voltages and apply a bias voltage to at least one of the first and second output drivers to vary the point where the first and second output voltages cross-over as the input voltage changes from a first to a second level.Type: ApplicationFiled: June 30, 2003Publication date: December 30, 2004Inventor: James D. Patterson
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Publication number: 20040263213Abstract: A constant current source extending the common-mode range comprises a differential pair of transistors connected to a third current source driving transistor. In an embodiment of the invention, the drains of the differential pair are coupled so as to obtain a common-mode voltage. The gate of the third transistor is connected to the drains of the differential pair in order to regulate current flowing through the third transistor. As the voltage decreases at the drain of the third transistor, the gate voltage on the third transistor increases to compensate for the lost voltage on the drain, thereby keeping the current constant even as the third transistor exits the saturation region.Type: ApplicationFiled: June 26, 2003Publication date: December 30, 2004Inventors: Oliver Kiehl, John A. Fifield
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Publication number: 20040257120Abstract: A voltage monitor circuit for biasing a well region of a CMOS circuit includes a self-biased comparator which compares first (INP) and second (INN) input signals. The comparator includes first (MN1) and second (MN2) N-channel transistors with grounded sources, a drain of the first N-channel transistor and a gate of the second N-channel transistor being coupled to a first output (OUTN), and a drain of the second N-channel transistor and a gate of the first N-channel transistor being coupled to a second output (OUTP). First (MP1) and second (MP2) P-channel transistors are operated to couple the second or first input signal to the second or first output, respectively, by controlling the gate-to-source voltage of the first or second P-channel transistor according to the polarity of a voltage difference between the first and second input signals.Type: ApplicationFiled: June 19, 2003Publication date: December 23, 2004Inventors: Binan Wang, Paul Stulik
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Publication number: 20040257121Abstract: A data transfer apparatus is composed of a transmitter and a receiver. The transmitter includes an output buffer developing a differential signal in response to a data signal, and an amplitude controller. The receiver includes an input buffer converting the differential signal into a single-end signal, and an amplitude detector developing a feedback signal in response to the single-end signal. The amplitude controller controls an amplitude of the differential signal in response to the feedback signal.Type: ApplicationFiled: June 18, 2004Publication date: December 23, 2004Applicant: NEC ELECTRONICS CORPORATIONInventors: Yoshihiko Hori, Keiichi Nakajima
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Patent number: 6833738Abstract: A signal reception circuit capable of detecting and receiving a signal at a high speed having small amplitude, and a data transfer control device and electronic equipment using the same. A differential pair of reception signals DP and DM is detected by an HS_SQ_L circuit for low speed having high receiving sensitivity and an HS_SQ circuit for high speed having high speed response performance. In the case of a high-speed reception signal, a logical product of a signal HS_DataIn fetched by an HS differential data receiver and a signal HS_SQ indicating the result of signal detection by the HS_SQ circuit for high speed is supplied to a DLL circuit. In the case of a low-speed reception signal, an FS differential receiver is activated after the detection of differential pair of reception signals DP and DM by the HS_SQ_L circuit for low speed. A signal FS_DataIn fetched by the FS differential receiver is supplied to an FS circuit.Type: GrantFiled: May 10, 2002Date of Patent: December 21, 2004Assignee: Seiko Epson CorporationInventor: Akira Nakada
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Publication number: 20040239373Abstract: According to the present invention, there is provided a semiconductor laser driving circuit including a differential output unit which performs differential amplification by receiving complementary input signals, and outputs complementary signals from first and second output terminals, having:Type: ApplicationFiled: February 18, 2004Publication date: December 2, 2004Applicant: KABUSHIKI KAISHA TOSHIBAInventor: Toshiki Seshita
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Publication number: 20040239374Abstract: The intermediate node of the first terminator connected between a pair of signal lines transmitting the first differential signal with one side of the third differential signal as a common voltage and the intermediate node of the second terminator connected between a pair of signal lines transmitting the second differential signal with the other side of the third differential signal as a common voltage are connected by the intermediate connection. Thus, the intermediate node of the first terminator and the intermediate node of the second terminator act as a virtual ground of the third differential signal, enabling the matching of the impedance of the terminators related to the third differential signal and the impedance of the signal lines related to the third differential signal. It is thus able to prevent the reflection of the third differential signal.Type: ApplicationFiled: May 17, 2004Publication date: December 2, 2004Applicant: NEC Electronics CorporationInventor: Yoshihiko Hori
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Publication number: 20040239372Abstract: The differential signal squarer/limiter and balancer circuit includes: a complementary differential pair MP5, MP6, MN2, and MN3; and a complementary positive feedback amp MP11, MP12, MN12, and MN13 coupled to the complementary differential pair.Type: ApplicationFiled: May 30, 2003Publication date: December 2, 2004Inventors: Chih-Ming Hung, Chien-Chung Chen, Dirk Leipold
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Publication number: 20040227544Abstract: Various circuit techniques for implementing ultra high speed circuits use current-controlled CMOS (C3MOS) logic fabricated in conventional CMOS process technology. An entire family of logic elements including inverter/buffers, level shifters, NAND, NOR, XOR gates, latches, flip-flops and the like are implemented using C3MOS techniques. Optimum balance between power consumption and speed for each circuit application is achieve by combining high speed C3MOS logic with low power conventional CMOS logic. The combined C3MOS/CMOS logic allows greater integration of circuits such as high speed transceivers used in fiber optic communication systems. The C3MOS structure enables the use of a power supply voltage that may be larger than the voltage required by the CMOS fabrication process, further enhancing the performance of the circuit.Type: ApplicationFiled: June 25, 2004Publication date: November 18, 2004Inventors: Guangming Yin, Ichiro Fujimori, Armond Hairapetian
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Patent number: 6819145Abstract: In general, the embodiments introduce a pre-charge state between an idle state (when no data in being transmitted) and an active state (when data is being transmitted). In the pre-charge state, both differential signals are pre-charged to the common mode voltage, which is also the crossover voltage. Similarly, an additional pre-charge state is inserted between the active state and the idle state when the signals transition from active to idle. Because both signals for each bit, including the first and last bits, are being driven from the same voltage level, the quality of the first and last bits are improved to be similar in quality to the middle bits.Type: GrantFiled: June 28, 2002Date of Patent: November 16, 2004Assignee: Intel CorporationInventors: Ronald W. Swartz, Yoon San Ho
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Publication number: 20040222822Abstract: Provided is a circuit to convert input CMOS level signals having a predetermined duty cycle to CML level signals having a higher duty cycle. The circuit includes two differential transistor pairs connected together. The two differential pairs are constructed and arranged to use gates of the associated transistors as inputs to receive and combine a number of phase shifted CMOS input signals. The combined CMOS input signal are converted to CML level signals which are provided as circuit outputs.Type: ApplicationFiled: June 16, 2004Publication date: November 11, 2004Applicant: Broadcom CorporationInventor: Ka Lun Choi
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Publication number: 20040222821Abstract: A differential line driver includes a plurality of driver cells. Control logic outputs positive and negative control signals to the driver cells so as to match a combined output impedance of the driver cells at (Vop, Von). Each driver cell includes an input Vip and an input Vin, an output Vop and an output Von, a first PMOS transistor and a first NMOS transistor having gates driven by the input Vip, and a second PMOS transistor and a second NMOS transistor having gates driven by the input Vin. A source of the first PMOS transistor is connected to a source of the second PMOS transistor. A source of the first NMOS transistor is connected to a source of the second NMOS transistor. First and second resistors are connected in series between the first PMOS transistor and the first NMOS transistor, and connected together at Von. Third and fourth resistors are connected in series between the second PMOS transistor and the second NMOS transistor, and connected together at Vop.Type: ApplicationFiled: June 8, 2004Publication date: November 11, 2004Applicant: Broadcom CorporationInventors: David Seng Poh Ho, Wee Teck Lee
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Patent number: 6812770Abstract: An exponentially variable gain mixer circuit includes an oscillating circuit generating an alternating differential signal. A correction circuit is connected to the oscillating circuit and includes a first amplifier and a differential amplifier. The first amplifier receives an external gain variation command and generates a differential output signal that includes a control voltage and a bias voltage. The differential amplifier receives the alternating differential signal and generates a differential modulation signal. A variable gain mixer receives an input differential signal and generates an amplified differential signal as a function of the differential modulation signal and the control voltage.Type: GrantFiled: January 28, 2003Date of Patent: November 2, 2004Assignee: STMicroelectronics S.r.l.Inventors: Pietro Filoramo, Angelo Granata
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Patent number: 6812757Abstract: A phase lock loop circuit including a voltage controlled oscillator and a phase detector having a sampling circuit and a linear voltage-to-current converter to create a control voltage for the voltage controlled oscillator. The phase lock loop circuit comprising a voltage-to-current circuit to influence a voltage on a capacitor, the voltage controlled oscillator responsive to the voltage on the capacitor, and the sampling circuit responsive to the first and second clock signals to generate two voltage values.Type: GrantFiled: May 14, 2002Date of Patent: November 2, 2004Assignee: Intel CorporationInventors: Michael Pang-Cheng Hsu, Rajendran Nair, Stephen R. Mooney
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Patent number: 6809566Abstract: A differential-to-single-ended (DSE) converter receives a positive differential input and a negative differential input and generates a single-ended output. The DSE converter comprises: 1) a first comparator having a non-inverting input coupled to the positive differential input and an inverting input coupled to the negative differential input; 2) a second comparator having an inverting input coupled to the positive differential input and a non-inverting input coupled to the negative differential input; 3) a first D flip-flop having a Logic 1 input and clocked by a rising edge on the first comparator output; 4) a second D flip-flop having a Logic 1 input and clocked by a rising edge on the second comparator output; and 5) a latch circuit having a first input coupled to the first D flip-flop output and a second input coupled to the second D flip-flop output. Rising edges on the first and second D flip-flop outputs cause the latch output to change state.Type: GrantFiled: July 30, 2003Date of Patent: October 26, 2004Assignee: National Semiconductor CorporationInventor: Jane Xin-LeBlanc
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Patent number: 6806743Abstract: The present invention provides a semiconductor integrated circuit device equipped with an input circuit capable of stably performing a high-speed operation up to a low voltage. A rail to rail circuit constitutes a differential input circuit, and a circuit similar to such a differential input circuit is used to constitute a bias circuit. A pair of output terminals of a differential circuit constituting such a bias circuit is commonly connected to form a bias voltage corresponding to a middle point. The bias voltage is supplied to the gates of current source MOSFET and the gates of cascode-connected MOSFETs in the differential input circuit, and the gates of the corresponding current source MOSFETs and cascode-connected MOSFETs in the bias circuit corresponding to itself.Type: GrantFiled: February 10, 2003Date of Patent: October 19, 2004Assignee: Renesas Technology Corp.Inventors: Kayoko Saito, Mitsugu Kusunoki
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Patent number: 6806744Abstract: A method and system is arranged to convert a differential low-voltage input signal (e.g. LVDS or RSDS) into a single-ended output signal. An operational trans-conductance amplifier (OTA) is configured to convert the input signal into a current. A trans-impedance stage is configured to convert the current into the single-ended output signal. The voltage associated with the output of the OTA corresponds to approximately VDD/2. The trans-impedance stage comprises an inverter circuit, a p-type transistor, and an n-type transistor. The transistors are arranged in a negative feedback configuration with the inverter. The single-ended output signal has a voltage swing that approximately corresponds to the sum of the VGS of the n-type transistor and the VGS of the p-type transistor. The output signal may be buffered by additional circuits such as an inverter, a Schmitt, as well as others.Type: GrantFiled: October 3, 2003Date of Patent: October 19, 2004Assignee: National Semiconductor CorporationInventors: Marshall J. Bell, David B. Cooper, James Kozisek
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Patent number: 6803795Abstract: A comparator circuit includes a differential amplifier including load resistors, for amplifying difference between two input voltages of the comparator circuit; an emitter follower circuit for applying positive feedback with respect to a differential amplifier and outputting an output voltage of the comparator circuit; and a grounded-base amplifier, and outputting an output voltage of the comparator circuit, for realizing both voltage output and current output. A grounded-base amplifier includes two transistors each of which has a base supplied with a reference voltage. The differential amplifier includes two load resistors respectively connected to each emitter of the transistors of the grounded-base amplifier. The load resistor flowing a current which is obtained through a collector of the transistor as an output current of the comparator. With this arrangement, it is not necessary to provide a current switch circuit for obtaining current output of the comparator circuit.Type: GrantFiled: August 22, 2003Date of Patent: October 12, 2004Assignee: Sharp Kabushiki KaishaInventors: Akio Nakajima, Kohichi Furuta, Takao Matsui
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Patent number: 6803800Abstract: A negative voltage switch for use in flash memory. The switch has a control end and two voltage output ends, and includes two inverting units for transferring a positive voltage, two driving units for transferring a negative voltage, and two negative voltage pass-gate transistors for respectively transferring the negative voltage to the voltage outputs. Each inverting unit connects to a driving unit at a corresponding node, and each negative voltage pass-gate transistor connects to one of the nodes. According to a voltage at the control end, the switch turns on one inverting unit to transfer the positive voltage at the corresponding node, and the driving unit connected to the other node turns on to transfer the negative voltage to the corresponding negative voltage pass-gate transistor such that the negative voltage pass-gate transistor stops outputting the negative voltage at the other voltage output.Type: GrantFiled: March 19, 2003Date of Patent: October 12, 2004Assignee: AMIC Technology CorporationInventor: Yin-Chang Chen
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Patent number: 6801059Abstract: A comparator according to the present invention can generate an output signal of low or high level by comparing a first and second input voltages that have a common voltage. An input stage circuit of a comparator according to the present invention receives a common voltage detection signal. The common voltage is supplied with a first offset voltage when the common voltage detection signal is on low level, and the common voltage is supplied with a second offset voltage when the common voltage detection signal is on high level. Then, the input stage circuit performs amplification to output a voltage difference between the first input voltage and the second input voltage to the comparator. Accordingly, the comparator with offset voltage according to the present invention can sufficiently amplify the input signal difference of low common voltage by selectively applying different offset voltages to a common voltage in accordance with the common voltage level of the input signal.Type: GrantFiled: July 25, 2002Date of Patent: October 5, 2004Assignee: Hyundai Electronics Industries Co., Ltd.Inventor: Jung-Bong Lee
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Publication number: 20040189350Abstract: Two groups of diodes are connected to internal lines transmitting complementary signals, respectively, and positions of the centers of gravity of the groups of diodes are made coincident with each other. A circuit capable of preventing the deviation of the characteristics of differential transistor pair caused by an antenna effect and highly immune against a substrate noise can be achieved.Type: ApplicationFiled: July 10, 2003Publication date: September 30, 2004Applicant: RENESAS TECHNOLOGY CORP.Inventors: Yasuo Morimoto, Toshio Kumamoto, Takashi Okuda
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Patent number: 6798251Abstract: Described is a differential clock receiver comprising a converter, a differential input stage, and a differential output stage. The converter converts a control signal indicative of a timing relationship into a DC offset signal. The differential input stage receives a differential clock signal and the DC offset signal. The differential input stage generates an intermediary differential signal from the differential clock. The intermediary differential signal has a DC offset resulting from the DC offset signal. The differential output stage receives the intermediary differential signal and generates at least two output signals from the intermediary differential signal. The output signals have a timing relationship determined by the DC offset of the intermediary differential signal.Type: GrantFiled: August 13, 2002Date of Patent: September 28, 2004Assignee: Analog Devices, Inc.Inventor: Bernd Schafferer
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Patent number: 6791371Abstract: A power-down mode is activated when equal voltages are detected on a pair of differential inputs. The voltage difference across the differential inputs is applied to a multiplier, which generates a squared difference. The squared difference is smoothed and filtered by a low-pass filter to produce an average signal. The average signal is compared to a reference voltage, either explicitly or implicitly, to detect when the voltage difference across the differential inputs is too small. A power-down signal is activated when the average signal is too small. The multiplier can be implemented with a Gilbert cell, while a filter-comparator converts the differential Gilbert-cell output to a single-ended signal and filters the signal. The reference voltage compared can be set by the switching threshold of the filter comparator or other logic gates. A complementary Gilbert cell and filter-comparator can be used to increase the operating range.Type: GrantFiled: March 27, 2003Date of Patent: September 14, 2004Assignee: Pericom Semiconductor Corp.Inventor: Hung-Yan Cheung
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Patent number: 6791372Abstract: An active cascode differential latch for providing a logic output signal indicative of whether or not a first current is greater than a second current. The first and second currents are fed into two input ports of the active cascode differential latch. The active cascode differential latch has a relatively small input impedance, and has utility for comparators and discrete-time analog filters, to name just a few, particularly when used in high bandwidth and low voltage applications.Type: GrantFiled: June 4, 2002Date of Patent: September 14, 2004Assignee: Intel CorporationInventor: James E. Jaussi
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Publication number: 20040174191Abstract: The present invention is related to a device comprising, between a differential pair of inputs, a differential pre-amplifier (HPA1, HPA2), an offset-reducing block (ORB) cascaded with said differential pre-amplifier (HPA1, HPA2) and arranged for reducing the offset generated by said differential pre-amplifier, and a buffering block (BB) in series with said offset-reducing block (ORB) and arranged for amplifying and buffering the output voltage of said offset-reducing block.Type: ApplicationFiled: February 9, 2004Publication date: September 9, 2004Applicant: ALCATELInventor: Andrzej Gajdardziew Radelinow
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System and method for effectively implementing an active termination circuit in an electronic device
Patent number: 6788099Abstract: A system and method for effectively transferring electronic information in an electronic device may include a transmission line that connects a source device and a destination device. The foregoing transmission line may be implemented to include a conductor A and a conductor B for transferring the electronic information. One or more active termination circuits may coupled to conductor A and conductor B for being dynamically switched between a differential mode termination configuration and a single-ended mode termination configuration with respect to the transmission line. Control logic may be configured to dynamically place the active termination circuit into the foregoing differential mode termination configuration during a differential transmission mode. Alternately, the control logic may place the active termination circuit into the foregoing single-ended mode termination configuration during a single-ended transmission mode.Type: GrantFiled: December 16, 2002Date of Patent: September 7, 2004Assignees: Sony Corporation, Sony Electronics Inc.Inventor: Rehan A. Zakai -
Patent number: 6784818Abstract: An N-bit analog to digital converter includes a reference ladder connected to an imput voltage at one end, and to ground at another end, an array of differential amplifiers whose differential inputs are connected to taps from the reference ladder, wherein each amplifier has a first differential input connected to the same tap as a neighboring amplifier, and a second differential imput shifted one tap from the neighboring amplifier, and an encoder that converts outputs the array to an N-bit output.Type: GrantFiled: December 31, 2003Date of Patent: August 31, 2004Assignee: Broadcom CorporationInventor: Jan Mulder
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Patent number: 6781445Abstract: Methods and apparatus for buffering RF signals. A method includes receiving an input signal, wherein the input signal alternates between a first polarity and a second polarity. From the input signal, a first current is generated, wherein the first current is proportional to the input signal when the input signal has the first polarity, and approximately equal to zero when the input signal has the second polarity, and a second current is generated, wherein the second current is proportional to the input signal when the input signal has the second polarity, and approximately equal to zero when the input signal has the first polarity. A third current is generated proportional to the first current, and a fourth current is generated proportional to the second current. The first and fourth currents are applied to a first terminal of an inductor; and the second and third currents are applied to a second terminal of the inductor.Type: GrantFiled: April 13, 2001Date of Patent: August 24, 2004Assignee: Zeevo, Inc.Inventor: Arnold R. Feldman
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Publication number: 20040160245Abstract: A low noise transconductance cell includes a resistor and a differential circuit pair having two equivalent half-circuits. Each half-circuit includes a feedback loop coupled to the resistor. The feedback loop includes an input transistor coupled to an inverting gain stage. The inverting gain stage is coupled to an output transistor which in turn is coupled to the input transistor and the resistor. In a low noise transconductance cell, a bias current source is coupled to the center of series connected resistors. In a high swing transconductance cell, a first bias current source is coupled to the left terminal of a resistance stage and a second bias current source is coupled to the right terminal of the resistance stage. The resistance stage can include a single resistor or a plurality of resistors.Type: ApplicationFiled: February 13, 2004Publication date: August 19, 2004Inventors: Todd Brooks, Jungwoo Song, Wynstan Tong
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Patent number: 6777983Abstract: A differential voltage transmission circuit. The reference bias circuit outputs a first reference voltage, a second reference voltage and a reference current corresponding to a reference current adjusting signal. The differential comparator compares the difference between the first reference voltage and the second reference voltage with the difference between a first output voltage and a second output voltage, and outputs a result signal corresponding to the compared result. The decision circuit outputs the reference current adjusting signal corresponding to the result signal. The output circuit outputs the first output voltage and the second output voltage generated at both terminals of a termination resistor when the reference current flows through the termination resistor.Type: GrantFiled: May 22, 2003Date of Patent: August 17, 2004Assignee: Faraday Technology Corp.Inventors: Shin-Lin Wang, Kun-Chih Chang
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Publication number: 20040155682Abstract: A sense amplifier has a pair of internal nodes that are precharged to a power-supply level. A first pair of n-channel transistors supplies current to the internal nodes responsive to a pair of data signals, both of which are initially high. When one of the data signals begins falling toward the low level, the corresponding n-channel transistor immediately reduces the current supplied to one of the internal nodes. A second pair of n-channel transistors, cross-coupled to the internal nodes, amplifies the resulting potential difference between the internal nodes, thereby pulling down the potential of one of the internal nodes. An output signal is generated from one or both of the internal nodes. The output signal is obtained quickly, because amplification begins without delay.Type: ApplicationFiled: June 19, 2003Publication date: August 12, 2004Inventor: Yukio Sato
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Publication number: 20040150430Abstract: A differential driver includes a switching module and first and second voltage controlled voltage sources. The switching module has a plurality of switches each controlled by an input signal, a first voltage input and a second voltage input, and a signal output. The first voltage controlled voltage source is connected to the first voltage input. The first voltage controlled voltage source has a low impedance. The second voltage controlled voltage source is connected to the second voltage input. The second voltage controlled voltage source also has a low impedance. The switching circuit outputs an output signal having an output voltage and current controlled by the first and second voltage controlled voltage sources. The output signal is based upon the input signal.Type: ApplicationFiled: December 30, 2003Publication date: August 5, 2004Applicant: Broadcom CorporationInventors: Ning Li, Jiann-Chyi (Sam) Shieh
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Patent number: 6768442Abstract: An Advanced Digital Antenna Module (ADAM) for receiving and exciting electromagnetic signals. The ADAM ASIC integrates a complete receiver/exciter function on a monolithic SiGe device, enabling direct digital-to-RF (Radio Frequency) and RF-to-digital transformations. The invention includes an improved analog-to-digital converter (ADC) (10) with a novel active offset method for comparators. The novel ADC architecture (10) includes a first circuit (12, 14) for receiving an input signal; a second circuit (18) for setting a predetermined number of thresholds using a predetermined number of preamplifiers (60) with weighted unit current sources (66) in each of the preamplifier outputs; and a third circuit (20) for comparing the input to the thresholds. In the preferred embodiment, the ADC (10) includes trimmable current sources (66). The ADC (10) of the present invention also includes an improved comparator circuit (62).Type: GrantFiled: October 25, 2002Date of Patent: July 27, 2004Assignee: Raytheon CompanyInventors: Clifford W. Meyers, Lloyd F. Linder, Kenneth A. Essenwanger, Don C. Devendorf, Erick M. Hirata, William W. Cheng
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Publication number: 20040140830Abstract: A differential line driver includes first, second, third and fourth cascode transistors connected in parallel, wherein drains of the first and third transistors are connected to a negative output of the differential line driver, and wherein drains of the second and fourth transistors are connected to a positive output of the differential line driver. First, second, third and fourth switching transistors are connected in series with corresponding first, second, third and fourth cascode transistors and driven by a data signal. First and second compound transistors inputting a class AB operation signal at their gates, wherein the first compound transistor is connected to sources of the first and second switching transistors, and wherein the second compound transistor is connected to sources of the third and fourth switching transistors.Type: ApplicationFiled: November 25, 2003Publication date: July 22, 2004Applicant: Broadcom CorporationInventors: Jan Mulder, Yee Ling Cheung
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Publication number: 20040135598Abstract: An input circuit for preventing the application of a voltage exceeding a transistor withstand voltage when the input circuit is switched to a standby state. The input circuit includes a first differential amplification circuit powered by a first power supply to amplify a first input signal and generate a second input signal. A level shift circuit is powered by the first power supply to generate a shifted input signal from the second input signal. A second differential amplification circuit is powered by a second power supply to amplify the shifted input signal and generate an amplified signal. A current control circuit selectively switches the input circuit between activated and standby states. A first circuit charges or discharges the level shift circuit so that voltage of the shifted input signal is less than or equal to voltage of the second power supply when switched to the standby state.Type: ApplicationFiled: January 5, 2004Publication date: July 15, 2004Applicant: FUJITSU LIMITEDInventor: Tomohiko Koto
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Patent number: 6762628Abstract: The invention relates to a method for operating a comparator (10) and a pre-amplifier (20) of an integrated circuit, which pre-amplifier is connected in series to the comparator, wherein the comparator (10) is operated with clock pulses in order to compare comparator input signals at periodical decision points (t2), wherein the pre-amplifier (20) is operated with clock pulses so as, in amplification phases (t1 to t2) which precede the decision points (t2), to amplify a signal (IN) which has been input to the pre-amplifier, and to provide the amplified signal (OUT) as a comparator input signal, and so as, in reset phases (t0 to t1) which precede the amplification phases (t1 to t2), to reset the amplification (G) to a minimum value. According to the invention, the pre-amplifier (20) is operated such that its amplification (G) during a rise phase within the amplification phase (t1 to t2) rises gradually and uniformly from the minimum value to a maximum value.Type: GrantFiled: March 7, 2003Date of Patent: July 13, 2004Assignee: Xignal Technologies AGInventor: Christian Ebner
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Patent number: 6759701Abstract: MOS transistors A and B form a transistor circuit (an inverter in this case). A MOS transistor D is one for interrupting leakage current that has a channel length longer than those of the MOS transistors A and B. Under the action of an enable terminal (Enable), the MOS transistor D conducts only while the circuit is operated, and does not conduct and thereby interrupts leakage current while the circuit is in a standby state. A MOS transistor C does not produce effect while the circuit is operated, and makes the potential of an output terminal (Output) a high potential or a low potential (not intermediate potential) only while the circuit is in the standby state. Therefore, the circuit controls unnecessary through-transistor current of a standby type circuit in a succeeding stage, which current is conventionally caused at an intermediate potential during standby.Type: GrantFiled: September 18, 2001Date of Patent: July 6, 2004Assignee: Sony CorporationInventor: Kazutoshi Shimizume
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Patent number: 6759887Abstract: A mixer circuit includes a local frequency multiplication unit including a pair of transistors having bases receiving local oscillation waves inverted in phase. A reference transistor is differentially connected with the pair of transistors. The pair of transistors and the reference transistor have their emitters connected to a collector of a modulated wave input transistor having a base receiving a modulated wave signal and an emitter connected to a constant current source, and have their collectors connected to a load. The commonly connected collectors of the pair of transistors and the collector of the reference transistor output modulation signals inverted in phase. The sum of currents flowing through the pair of transistors and the reference transistor equals the constant current of the constant current source flowing through the modulated wave input transistor, and the mixer circuit has a gain.Type: GrantFiled: June 18, 2003Date of Patent: July 6, 2004Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Yoshinori Takahashi, Hiroyuki Joba
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Publication number: 20040124888Abstract: A Low Voltage Differential Signaling [LVDS] Driver with Pre-emphasis and comprising a primary stage (MP3-MP6, MN3-MN6) having a first switching circuit (MP5, MP6, MN5, MN6) arranged to provide a sequence of pulses (OUT1; OUT2) at a predetermined current level (I1), a secondary stage (MP7-MP9, MN7-MN9) having a second switching circuit (MP8, MP9, MN8, MN9) arranged to provide an additional current level (I2) for the pulses, and a control circuit arranged to provide control signals (A,{overscore (A)},B,{overscore (B)}) for controlling the first and second switching circuits. The control circuit is adapted to detect a difference in level between two consecutive pulses of the sequence and to provide accordingly control signals (A,{overscore (A)},B,{overscore (B)}) to the first (MP5, MP6, MN5, MN6) and second (MP8, MP9, MN8, MN9) switching circuits.Type: ApplicationFiled: December 17, 2003Publication date: July 1, 2004Applicant: ALCATELInventor: Andrzej Gajdardziew Radelinow
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Publication number: 20040124886Abstract: The invention involves a component with a connection (3b), as well as at least one further connection (3a), whereby differential input clock pulses (CLK, CLKT; /CLK, /CLKT) can be applied to the connections (3a, 3b), or a single input clock pulse (CLK, CLKT) applied to the connection (3b) and/or to the further connection (3a)-, and where the component in addition has a first and a second pulse relay device (50, 51), where the first pulse relay device (50) has been provided for relaying differential input clock pulses (CLK, CLKT; /CLK, /CLKT), and the second pulse relay device (51) for relaying a single input clock pulse (CLK, CLKT).Type: ApplicationFiled: September 10, 2003Publication date: July 1, 2004Applicant: Infineon Technologies AGInventors: Andre Schaefer, Johann Pfeiffer, Kazimierz Szczypinski