With Latching Type Element (e.g., Flip-flop, Etc.) Patents (Class 327/57)
  • Patent number: 6060912
    Abstract: A strobed comparator circuit with reduced signal propagation time has a regenerative latch in which, during the reset phase of operation, its output nodes are discharged to a common potential which is close to the regenerative voltage level of the cross-coupled transistors forming such regenerative latch rather than to circuit ground. Accordingly, overall signal propagation time is reduced by the amount of reduction in charging time necessary for one of the discharged nodes to recharge above the threshold voltage of one of the cross-coupled latch transistors. Also included is an output monitoring circuit which determines whether the regenerative latch has remained in a metastable state.
    Type: Grant
    Filed: September 19, 1997
    Date of Patent: May 9, 2000
    Assignee: National Semiconductor Corporation
    Inventors: Ion E. Opris, Laurence D. Lewicki
  • Patent number: 6046609
    Abstract: A sense amplifier, which is intended to reduce the output response time after it has received a small voltage difference until it delivers amplified output signals, consists of a latch circuit made up of a pair of CMOS inverters, a pair of NMOS transistors connected in parallel to the latch circuit, and a current source connected in series to the latch circuit and NMOS transistor pair. The NMOS transistors amplify a small voltage difference of input signals, and the inverters of the latch circuit further amplify the resulting voltage difference to produce the output signals. Based on is a small voltage difference of input signals being amplified in two stages and the amplifying circuit being a 2-stage serial connection of the current source and the NMOS transistor or CMOS inverter, the delay time of output response can be reduced.
    Type: Grant
    Filed: November 10, 1998
    Date of Patent: April 4, 2000
    Assignees: Hitachi, Ltd., Hitachi ULSI Engineering Corp.
    Inventors: Hiroshi Toyoshima, Masashige Harada, Tomohiro Nagano, Yoji Nishio, Atsushi Hiraishi, Kunihiro Komiyaji, Hideharu Yahata, Kenichi Fukui, Hirofumi Zushi, Takahiro Sonoda, Haruko Kawachino, Sadayuki Morita
  • Patent number: 6037808
    Abstract: An integrated circuit (SAI.sub.0) comprises a first SOI transistor (T4) comprising a plurality of nodes, the plurality of nodes comprising a first source/drain, a second source/drain, a gate for receiving a potential to enable a conductive path between the first source/drain and the second source/drain, and a body terminal coupled to a body region disposed between the first source/drain and the second source/drain. The integrated circuit further includes a second SOI transistor (T5) comprising a plurality of nodes, the plurality of nodes comprising a first source/drain, a second source/drain, a gate for receiving a potential to enable a conductive path between the first source/drain and the second source/drain, and a body terminal coupled to a body region disposed between the first source/drain and the second source/drain. In the integrated circuit, one of the plurality of nodes of the first SOI transistor is connected to receive a first differential input signal.
    Type: Grant
    Filed: December 24, 1997
    Date of Patent: March 14, 2000
    Assignee: Texas Instruments Incorporated
    Inventors: Theodore W. Houston, Patrick W. Bosshart
  • Patent number: 6031775
    Abstract: A memory has a sense amplifier that provides data onto a global data line that is received by a secondary amplifier. The sense amplifier is precharged to a high voltage and responds to data provided by a selected memory cell on a pair of bit lines. The amplifier is a dynamic amplifier that latches the data but also limits the output voltage swing provided to the secondary amplifier. By limiting the voltage swing on the high-capacitance global data lines, there is significant power savings. The voltage swing that is provided is sufficient for reliable detection by the secondary amplifier.
    Type: Grant
    Filed: March 1, 1999
    Date of Patent: February 29, 2000
    Assignee: Motorola Inc.
    Inventors: Ray Chang, William R. Weier
  • Patent number: 6028455
    Abstract: 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: Grant
    Filed: December 19, 1997
    Date of Patent: February 22, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Hiroyuki Yamauchi
  • Patent number: 6018260
    Abstract: A novel latch circuit configuration that substantially reduces inverter-based setup and hold times. The latch circuit includes first and second input switches connected to an effective sense amplifier configuration. It is possible for the input switches to receive complementary signals of a balanced input signal. The latch circuit operates in initialization and output modes based on the signal level of an alternating clock signal. The output mode produces an output signal having a first or second signal magnitude based on the magnitude of the input signal at the end of the initialization mode. Also, disclosed is a high-speed serial-to-parallel converter based on this latch circuit.
    Type: Grant
    Filed: August 6, 1997
    Date of Patent: January 25, 2000
    Assignee: Lucent Technologies Inc.
    Inventor: Thaddeus John Gabara
  • Patent number: 6002275
    Abstract: A circuit and method are disclosed herein which convert signal values on first and second complementary outputs of a second sense amplifier to a single ended data signal for transmission on a read write drive (RWD) line. The circuit includes first and second followers coupled to the first and second complementary outputs, an inverter coupled to an output of the first follower, and a signal driver responsive to an output of the inverter and the second follower to drive signal levels on said RWD line between a first level representing a first data state and a second level representing a second data state.
    Type: Grant
    Filed: February 2, 1998
    Date of Patent: December 14, 1999
    Assignee: International Business Machines Corporation
    Inventors: Kohji Hosokawa, Toshiaki Kirihata
  • Patent number: 6002270
    Abstract: A synchronous differential logic system is provided for implementation of pipelined computational structures capable of hyperfrequency operation. An individual logic circuit has a differential cascode switch and a synchronous sense amplifier which operates as a latch. A plurality of differential inputs are connected to the differential cascode switch which produces complementary signals at first and second nodes. The cascode switch is connected to the synchronous sense latch which provides complementary output signals of the logic circuit. The synchronous sense latch comprises an equalization transistor and two cross-coupled inverters, each connected to first and second power supply buses. The equalization transistor is connected to the first and second outputs, of the logic gate and to a global system clock.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: December 14, 1999
    Assignee: Spaceborne, Inc.
    Inventor: Constantin C. Timoc
  • Patent number: 5990707
    Abstract: A system and method is provided having a flash analog-to-digital converter (ADC) that includes an input signal buffer, a plurality of identical voltage comparators, and a reference generator. A clock signal defines the time instances at which the instantaneous input signal voltage is compared against a plurality of reference voltages generated by the reference generator. The individual comparator consists of a an integrating amplifier stage followed by an analog latching stage and a digital latch. The integrating amplifier input is allowed to track the input signal continuously. The amplifier output voltage is forced to a voltage close to zero before each conversion cycle is initiated by the ADC clock. At the beginning of the conversion cycle, the amplifier output is released and its voltage will follow an excursion related to the integral of the input of the amplifier. At a predefined time moment later, the analog latch is activated.
    Type: Grant
    Filed: September 5, 1997
    Date of Patent: November 23, 1999
    Assignee: Cirrus Logic, Inc.
    Inventors: Marius Goldenberg, Russell Croman
  • Patent number: 5982692
    Abstract: A method and apparatus is provided for implementing a memory cell array having a performance-improved critical read path using a boost amplifier configuration. The memory bit line is broken into small segments with a boost amplifier and the bit line is connected to the input of the amplifier. The output of the amplifier drives the global bit line. The amplifier is turned "on" during a "read" and turned "off" during a "write". During a read, one memory cell within one array segment is turned on. The memory cell drives the differential signal on to the local bit line pair. Also during a read, the boost amplifier which attaches to that local bit line is enabled. The boost amplifier amplifies the input signal (local bit line pair) and drives that signal on to the global bit line. Since the bit line is broken into small segments with boost amplifiers, there are many boost amplifiers attached on the global bit line.
    Type: Grant
    Filed: August 1, 1997
    Date of Patent: November 9, 1999
    Assignee: International Business Machines Corporation
    Inventors: George McNeil Lattimore, Robert Anthony Ross, Jr., Gus Wai-Yen Yeung
  • Patent number: 5982203
    Abstract: A high performance "two stage" (or cascading) Self-resetting CMOS (SRCMOS) amplifier where the 2nd stage amplifier is self-timed off of the 1st stage. Also, the SRCMOS nature of this amplifier eliminates the need for additional reset clock signals. The net affect of this invention is that the sensing action of a SRAM cell can start sooner (relative to a single stage sensing scheme) thereby delivering the data to the outputs sooner while providing greater noise immunity when compared to traditional sense amplifiers.
    Type: Grant
    Filed: January 9, 1998
    Date of Patent: November 9, 1999
    Assignee: International Business Machines Corporation
    Inventor: Antonio R. Pelella
  • Patent number: 5963060
    Abstract: Briefly, in accordance with one embodiment of the invention, an integrated circuit includes: a latching sense amp circuit. The latching sense amp circuit is configured in the integrated circuit so that the signals to produce and latch an output signal consist essentially of a precharge pulse and a capture pulse.
    Type: Grant
    Filed: October 7, 1997
    Date of Patent: October 5, 1999
    Assignee: Intel Corporation
    Inventors: Hemmige D. Varadarajan, Jeffrey K. Greason
  • Patent number: 5949256
    Abstract: An asymmetric sense amplifier is disclosed for use with single-ended memory arrays. The sense amplifier has a bit input, a reference input, an enable input, and bistable output circuitry. The reference input may simply be tied to V.sub.DD. The bistable output circuitry includes first and second output nodes disposed between first and second pull-up/pull-down paths, respectively. The first pull-up and pull-down paths may include first pull-up and pull-down FET channels, respectively. The second pull-up and pull-down paths may include second pull-up and pull-down FET channels, respectively. The bistable output circuitry is operable to be stable in first and second states. In both states, the output nodes are at opposite potentials. The sense amplifier is asymmetrical in the following sense: Either the second pull-down FET channel is wider than the first pull-down FET channel, or the first pull-up FET channel is wider than the second pull-up FET channel, or both.
    Type: Grant
    Filed: October 31, 1997
    Date of Patent: September 7, 1999
    Assignee: Hewlett Packard Company
    Inventors: Kevin Zhang, Jenny R. Carman
  • Patent number: 5942918
    Abstract: A method for resolving differential signals is provided which quickly and efficiently recognizes signals by resolving differences between the signals using a resolving circuit which is powered by a clock signal. The resolving circuit operates with supply voltage levels as low as one threshold voltage. Also, the signal hold time can be made very small depending on the sizing of certain transistors. Other advantages include reduced power consumption, high speed operation, good rejection of input noise and power supply noise, ability to resolve small (e.g., 1.0 mVolt) voltage differences, and the ability to function with a variety of types of drivers, including HSTL, DTL and PECL.
    Type: Grant
    Filed: June 25, 1997
    Date of Patent: August 24, 1999
    Assignee: Sun Microsystems, Inc.
    Inventors: Michael A. Ang, Alexander D. Taylor, Jonathan E. Starr
  • Patent number: 5942919
    Abstract: A receiver is provided which quickly and efficiently recognizes signals by including with the receiver a resolving circuit which is coupled to a node control circuit which determines the signals to be recognized. The resolving circuit can operate with supply voltage levels as low as one threshold voltage. Also, the signal hold time can be made very small depending on the sizing of certain transistors. Other advantages include reduced power consumption, high speed operation, good rejection of input noise and power supply noise, ability to resolve small (e.g., 1.0 mVolt) voltage differences, and the ability to function with a variety of types of drivers, including HSTL, DTL and PECL.
    Type: Grant
    Filed: June 25, 1997
    Date of Patent: August 24, 1999
    Assignee: Sun Microsystems, Inc.
    Inventors: Michael A. Ang, Alexander D. Taylor, Jonathan E. Starr
  • Patent number: 5939903
    Abstract: A sense amplifier circuit is incorporated within a computer system and utilizes a latch coupled to an equalizing transistor that operates in the triode region and initially equalizes the sense amplifier circuit data outputs, the latch subsequently develops a voltage difference in response to a control signal, deactivation of the control signal then turns off the equalizing transistor thereby allowing the latch circuit to lock the developed voltage differential to full-swing across the sense amplifier data outputs.
    Type: Grant
    Filed: June 19, 1997
    Date of Patent: August 17, 1999
    Assignee: Cirrus Logic, Inc.
    Inventor: Jyhfong Lin
  • Patent number: 5940331
    Abstract: An output circuit of a semiconductor memory device is provided, which prevents a current from flowing through a pair of output transistors due to their ON-ON state.
    Type: Grant
    Filed: August 28, 1998
    Date of Patent: August 17, 1999
    Assignee: NEC Corporation
    Inventor: Akihiko Kagami
  • Patent number: 5936432
    Abstract: An amplifier circuit that maintains high speed and reduces power consumption while operating with reduced voltages is disclosed. Broadly, the amplifier circuit of the present invention includes a set-up circuit that performs a level shift on the input signal and applies it to the inputs of a sense amplifier in a cross-coupled fashion. The circuit operates such that one leg of the precharged sense amplifier output discharges in response to the input without a counteracting charging action by the other leg of the sense amplifier output. The amplifier circuit thus operates at higher speed and with no crowbar current even with input signals of smaller magnitude.
    Type: Grant
    Filed: October 20, 1997
    Date of Patent: August 10, 1999
    Assignee: Hyundai Electronics America, Inc.
    Inventors: Jong-Hoon Oh, Sitaram Kamath
  • Patent number: 5929660
    Abstract: A single-ended sense amplifier pre-charges the data output line of a bank of memory cells or register file to approximately the switch point of an inverter that is part of a buffer, in preparation for the next data read cycle. The amplifier includes a stack of six transistors connected in series between a supply voltage and ground. The memory output is connected to the stack mid-point, to a latch input and to a buffer input. The most recent binary logic level read from memory passes through the latch. The latch and stack are then clocked, and the three-transistor portion of the stack turned on pulls the voltage on the stack mid-point to approximately one-half the supply voltage, which is the buffer inverter switch point. The stack is then turned off, and the stack mid-point floats at that voltage value in preparation for the next read cycle. As such, the common data line needs only slew a relatively small amount of voltage during the next read cycle.
    Type: Grant
    Filed: December 29, 1997
    Date of Patent: July 27, 1999
    Assignee: United Technologies Corporation
    Inventor: Stephen C. Dillinger
  • Patent number: 5929659
    Abstract: A sense amplifier (10) senses data by sensing a differential current signal comprised of a current (I.sub.1) flowing in an input terminal (12) and a current (I.sub.2) flowing in a complementary input terminal (22). During the sensing process, the sense amplifier (10) generates a first current flowing in a first FET (17) in accordance with the current (I.sub.1) flowing through the input terminal (12) and a second current flowing in a second FET (27) in accordance with the current (I.sub.2) flowing through the complementary input terminal (22). Two cross coupled inverters (16, 26) compare the first current (I.sub.1) with the second current (I.sub.2) and generate a differential output voltage signal, thereby sensing the data.
    Type: Grant
    Filed: March 12, 1997
    Date of Patent: July 27, 1999
    Assignee: Motorola, Inc.
    Inventors: Dimitris C. Pantelakis, Wai Tong Lau, John Eagan
  • Patent number: 5912853
    Abstract: An amplifier 300 includes a differential pair of transistors 307a, 307b. A third transistor 306 controls current through transistors 307a, 307b of the differential pair in response to a stepped control signal.
    Type: Grant
    Filed: December 3, 1996
    Date of Patent: June 15, 1999
    Assignee: Cirrus Logic, Inc.
    Inventor: G. R. Mohan Rao
  • Patent number: 5903171
    Abstract: A sense amplifier having an ingegrated latch with level shift is disclosed, in which a pair of cross-connected inverters are connected between the outputs of the sense amplifier to provide a single stage amplifier. The sense amplifier performs level shift, sense amplifier and latching functions within a single circuit, thus reducing layout area and simplifying chip design while at the same time providing full swing complementary outputs. In addition, the sense amplifier is turned on for only a portion of the cycle to enable the data to be latched, with virtually no constant current comsumption in the circuit for holding the data, thereby reducing power consumption. Alternative embodiments are disclosed using conventional and tri-state latches.
    Type: Grant
    Filed: May 29, 1997
    Date of Patent: May 11, 1999
    Assignee: Winbond Electronics Corporation
    Inventor: Je-Hurn Shieh
  • Patent number: 5901087
    Abstract: A gain modulated sense amplifier, particularly for memory devices, that comprises a virtual ground latch structure which has two output nodes and which includes equalization transistor of a first polarity which equalizes the two output nodes and is connected between a first branch and a second branch, in which the output nodes are arranged; the equalization transistor is driven by an equalization signal whose slope can be modulated as a function of conductivity of a memory cell of the memory device.
    Type: Grant
    Filed: March 27, 1997
    Date of Patent: May 4, 1999
    Assignee: SGS--Thmomson Microelectronics S.r.l.
    Inventor: Luigi Pascucci
  • Patent number: 5896320
    Abstract: A semiconductor memory device comprises a bit line, a memory cell connected to the bit line, a sense amplifier, a power source for providing a first voltage to the sense amplifier as an operational power source voltage, a MOS transistor connected between the sense amplifier and the bit line and a stabilized power source for providing to a gate electrode of the MOS transistor a second voltage lower than the first voltage, so that a restore voltage of the memory cell is determined by the source voltage of the MOS transistor.
    Type: Grant
    Filed: May 12, 1995
    Date of Patent: April 20, 1999
    Assignee: Fujitsu Limited
    Inventor: Masao Taguchi
  • Patent number: 5894233
    Abstract: Sense amplifiers for integrated circuit memory devices including a bipolar transistor voltage gain input buffer and a first effect transistor latch circuit. The bipolar transistor voltage gain input buffer is responsive to a pair of complementary input signals from a memory cell, to amplify the voltage differential between the pair of complementary input signals. The field effect transistor latch circuit is responsive to the bipolar transistor voltage gain input buffer, to latch the voltage differential so amplified, and thereby produce a pair of complementary output signals.
    Type: Grant
    Filed: November 6, 1997
    Date of Patent: April 13, 1999
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Yong-jin Yoon
  • Patent number: 5892374
    Abstract: A latching comparator includes first and second current integration nodes having first and second integration capacitances, respectively. A current source applies a first tail current to a current steering circuit which steers the tail current onto the first and second current integration nodes as a function of first and second data signals. An offset adjustment circuit is coupled to the first current integration node for adjusting the first integration capacitance relative to the second integration capacitance. A latch circuit is coupled to the first and second current integration nodes and has a data output.
    Type: Grant
    Filed: June 26, 1997
    Date of Patent: April 6, 1999
    Assignee: LSI Logic Corporation
    Inventor: Alan Fiedler
  • Patent number: 5886938
    Abstract: A semiconductor memory device 10 having sense amplifiers where the latch transistor moat region width is increased for the same sense transistor pitch. Each sense amplifier comprises latch transistors having a moat region and a gate region comprising a plurality of gate fingers where the length of the gate fingers is determined by the pitch of the sense amplifier. Adjacent latch transistors are offset from one another in both the horizontal and vertical directions and the gate fingers of those latch transistors are interleaved such that the latch transistors have wider moat regions while maintaining the sense amplifier latch transistor pitch. The resulting structure increases the sensing performance while maintaining the pitch.
    Type: Grant
    Filed: October 28, 1997
    Date of Patent: March 23, 1999
    Assignee: Texas Instruments Incorporated
    Inventor: Brent S. Haukness
  • Patent number: 5886931
    Abstract: Feedback control is performed on the potential of a bit line in accordance with a change in the potential. Meanwhile, the data which has been previously read on the bit line is temporarily latched in a D-type flip-flop. A reference voltage Vref determined by a bias circuit is offset by using an offset circuit while referring to the level of the previously read data latched in the D-type flip-flop. In this manner, a bias voltage is obtained from currently read data, and based on the bias voltage, the potential of the bit line is controlled. Thus, high-speed data determining operation is achieved, which has been previously hampered when the currently read data is reversed with respect to the data read in the previous cycle.
    Type: Grant
    Filed: June 19, 1998
    Date of Patent: March 23, 1999
    Assignee: Sony Corporation
    Inventor: Akihiko Hashiguchi
  • Patent number: 5854562
    Abstract: A sense amplifier, which is intended to reduce the output response time after it has received a small voltage difference until it delivers amplified output signals, consists of a latch circuit made up of a pair of CMOS inverters, a pair of NMOS transistors connected in parallel to the latch circuit, and a current source connected in series to the latch circuit and NMOS transistor pair. The NMOS transistors amplify a small voltage difference of input signals, and the inverters of the latch circuit further amplify the resulting voltage difference to produce the output signals. Based on is a small voltage difference of input signals being amplified in two stages and the amplifying circuit being of 2-stage serial connection of the current source and the NMOS transistor or CMOS inverter, the delay time of output response can be reduced.
    Type: Grant
    Filed: April 15, 1997
    Date of Patent: December 29, 1998
    Assignees: Hitachi, Ltd, Hitachi ULSI Engineering Corp.
    Inventors: Hiroshi Toyoshima, Masashige Harada, Tomohiro Nagano, Yoji Nishio, Atsushi Hiraishi, Kunihiro Komiyaji, Hideharu Yahata, Kenichi Fukui, Hirofumi Zushi, Takahiro Sonoda, Haruko Kawachino, Sadayuki Morita
  • Patent number: 5844428
    Abstract: A novel driver circuit is disclosed that is used for driving a logic voltage sensed by a sensing amplifier of a memory onto a data line of the memory. The driver circuit is responsive to first sensing signals and second sensing signals that are delayed with respect to the first sensing signals. When the first and second sensing signals indicate that equalization is occuring in the sensing amplifier, the driver circuit latches the data line logic voltage on the data line without any false transitions or glitches occuring on the data line. In addition, the driver circuit becomes self biased when the first sensing signals indicate that sensing is occuring in the sensing amplifier but the second sensing signals indicate that equalization is still occuring. This is done to minimize the voltage swing in the driver circuit when the sensed logic voltage is driven onto the data line while both the first and second sensing signals indicate that sensing is occuring.
    Type: Grant
    Filed: May 2, 1997
    Date of Patent: December 1, 1998
    Assignee: Integrated Silicon Solution Inc.
    Inventor: Yong H. Jiang
  • Patent number: 5834953
    Abstract: A high speed current sense amplifier useful in memory devices, which includes a current-to-voltage amplifier that is coupled to a voltage amplifier. The current-to-voltage amplifier has an input impedance that is lower than its output impedance. The voltage amplifier has an input impedance that is larger than the input impedance of the current-to-voltage amplifier. The current sense amplifier can sense the current relationship between two current inputs in about 200 pico-seconds. Embodiments of the current sense amplifier enable current sensing either near the power supply voltage or near ground, thus eliminating the need for intermediate voltages. Embodiments of the current sense amplifier draw current from the current inputs only during the 200 pico-second sensing time and does not require external latching circuitry.
    Type: Grant
    Filed: November 25, 1996
    Date of Patent: November 10, 1998
    Assignee: Rockwell International Corporation
    Inventors: Kevin W. Glass, John R. Spence, Lester J. Pastuszyn, William W. Decker
  • Patent number: 5828241
    Abstract: A signal transmission circuit which enables the distance of signal transmission as measured by the length of the wiring electrically connecting a driver circuit and a receiver circuit of the signal transmission circuit to be increased, while the signal delay and power consumption are reduced. The signal transmission circuit includes the driver circuit, the receiver circuit, an equalizer circuit that flattens the output of the driver circuit, and an intermediate amplifier circuit. The intermediate amplifier circuit is connected to input/output shared terminals in the wiring that connects the driver circuit and the receiver circuit. With the aid of the positive feedback of the intermediate amplifier circuit, a differential signal output from the driver circuit is amplified and then transmitted to the receiver circuit.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: October 27, 1998
    Assignee: Texas Instruments Incorporated
    Inventor: Shunichi Sukegawa
  • Patent number: 5828239
    Abstract: A sense amplifier with improved compensation for clock skew effects is provided and includes a sense amplifier enabling mechanism for receiving first and second control signals. The sense amplifier further includes a first logic mechanism for providing the first control signal to a first input of the sense amplifier enabling mechanism, and a second logic mechanism for providing the second control signal to a second input of the sense amplifier enabling mechanism, wherein the first and second logic mechanisms reduce speed degradation by minimizing skew between the first and second control signals. In a method aspect, a method for reducing speed degradation in a sense amplifier includes providing a pull down device, and coupling the pull down device to first and second signal paths, the first signal path propagating a first clock signal and the second signal path propagating a second clock signal, for reducing speed degradation resulting from skew between the first and second clock signals.
    Type: Grant
    Filed: April 14, 1997
    Date of Patent: October 27, 1998
    Assignee: International Business Machines Corporation
    Inventor: Younes Lotfi
  • Patent number: 5821792
    Abstract: A current differential amplifier circuit comprises first and second pMOS transistors (P11 and P12) connected between a power supply and a first node (W11 ); third and fourth pMOS transistors (P13 and P14) connected between the power supply and a second node (W12); a fifth pMOS transistor (P15) connected between gates of the second and the third pMOS transistors (P12 and P13), each of the gates connected to its opposite node (W11 or W12 ); a first nMOS transistor (N16) connected between the first node (W11 ) and a first current source (I11 ) and having its gate connected to the second node (W12); and a second nMOS transistor (N17) connected between the second node (W12) and a second current source (I12) and having its gate connected to the first node (W11). Pre-charge signal (/PC) is applied to the gates of the first, fourth and the fifth pMOS transistors (P11, P14 and P15) and comparison results are derived from either the first node (W11) or the second node (W12).
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: October 13, 1998
    Assignee: NEC Corporation
    Inventor: Tohru Miwa
  • Patent number: 5808487
    Abstract: A signal transfer circuit for enabling rapids transfer of differential electrical signals among multiple signal paths is provided. The circuit comprises first and second pairs of signal transfer terminals, a pair of internal nodes, first and second pairs of isolation devices, a differential signal amplifier, a gain-enhancing cross-coupled pair of devices, and a precharge circuit. The first and second pairs of isolation devices are of a single device type and are coupled between respective ones of the signal transfer terminal pairs and the internal node pair. The isolation devices each have a control terminal for receiving an isolation control signal. The differential signal amplifier circuit is coupled to the internal nodes, and is comprised of complementary device types. The amplifier circuit has a control terminal for receiving an amplifier control signal for enabling the amplifier circuit.
    Type: Grant
    Filed: November 26, 1996
    Date of Patent: September 15, 1998
    Assignee: Hitachi Micro Systems, Inc.
    Inventor: Richard Stephen Roy
  • Patent number: 5808488
    Abstract: A timed bistable circuit is described which includes two inverters each having its input connected to the output of the other, an output of the circuit via a "buffer" and an input of the circuit via a controlled electronic switch. The supply terminals of the inverters are connected to the supply terminals of the circuit via another two controlled switches. A clock generator provides timing signals to control both the input switches to open or close and to control the supply switches to close or open when the input switches are open or closed respectively. To obtain a latch usable in a comparator at a high comparison frequency the offset referred to the input is reduced and made independent of the frequency by arranging two further electronic switches between the supply terminals of the inverters and the supply terminals which are controlled by a timing signal in such a way as to close with a predetermined delay with respect to the closure of the input switches and to open when input switches open.
    Type: Grant
    Filed: November 22, 1996
    Date of Patent: September 15, 1998
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Melchiorre Bruccoleri, Paolo Cusinato
  • Patent number: 5804992
    Abstract: A sense amplifier of a semiconductor memory device which increases a voltage difference between a bit line and a dummy line is disclosed. The sense amplifier includes: a sense amplifying unit which pre-charges voltages of a dummy line connected to a dummy cell and of a bit line connected to a memory cell by a first equalizing signal, and which senses and amplifies data from the memory cell by inputting the voltages of the dummy line and the bit line by a sense amplifier enable signal; and a voltage variable unit which adjusts the voltages of the dummy line and the bit line by a second equalizing signal, said voltage variable unit having a first voltage variable part which adjusts the voltage of the dummy line by the second equalizing signal and a second voltage variable part which adjusts the voltage of the bit line by the second equalizing signal.
    Type: Grant
    Filed: December 27, 1996
    Date of Patent: September 8, 1998
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventor: Sung-Han Lee
  • Patent number: 5801565
    Abstract: A high speed differential data latch includes identical master and slave flip-flops. The master flip-flop is driven by a differential input data signal while both flip-flops are driven by a shared differential clock signal. Each flip-flop includes: one differential amplifier for sequentially latching the differential input data signal to provide a differential output data signal; a second differential amplifier for generating two switched supply currents from the clock signal for powering the differential data amplifier; and a third differential amplifier cross-coupled to the differential data amplifier for providing positive feedback thereto for enhancing the latching speed. The differential output data signal follows the differential input data signal during one of the differential clock states and remains latched during the other differential clock state.
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: September 1, 1998
    Assignee: National Semiconductor Corporation
    Inventor: James R. Kuo
  • Patent number: 5796273
    Abstract: A sense amplifier has a pair of output terminals and a first pair of pull-up transistors. A second pair of transistors is connected between the output terminals and a pull-down node. The gate electrodes of the second pair are cross-coupled to the output terminals. A third pair of transistors is connected between the output terminals and the pull-down node and have gate electrodes coupled to input potentials. A fourth pair of transistors is connected between the output terminals and the pull-down node and also have gate electrodes coupled to input potentials.
    Type: Grant
    Filed: May 20, 1996
    Date of Patent: August 18, 1998
    Assignee: Samsung Electronics, Co., Ltd.
    Inventors: Tae-Sung Jung, Jung-Hoon Park
  • Patent number: 5789948
    Abstract: The present invention provides a sense amplifier with high speed and stable sensing capabilities under a low supplying voltage. In accordance with the present invention, there is disclosed a sense amplifier comprising: a voltage level shifter for shifting a voltage level of data from a memory cell in response to a sense amplifier enable signal; a current mirror type sense amplifying stage for amplifying the level-shifted data from the voltage level shifter to full range in response to the sense amplifier enable signal; and a driver means for driving the amplified data from the current mirror type sense amplifying stage.
    Type: Grant
    Filed: December 27, 1996
    Date of Patent: August 4, 1998
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventors: Seung Min Kim, Sung Jun Jang
  • Patent number: 5787042
    Abstract: To read out a data bit stored in a memory cell including a programmable resistor memory element, a first voltage is developed on a first sense node due to initiation of current flow through the memory element and a second voltage is developed on a second sense node due to current flow through a reference resistor. The first and second voltages are separately detected to generate a trip signal in response to a leading edge of either of the first and second voltages achieving a threshold level. A flip-flop circuit is conditioned by the trip signal to produce opposite logic signal voltages on the first and second sense nodes indicative of the binary value of the stored data bit.
    Type: Grant
    Filed: March 18, 1997
    Date of Patent: July 28, 1998
    Assignee: Micron Technology, Inc.
    Inventor: Donald M. Morgan
  • Patent number: 5757210
    Abstract: A latchable comparator including a comparator and a circuit having a reset input. When the comparator produces a first state, it is latched when the reset input is in the non-reset state. In this state, the comparator receives a comparison signal having a high or low value and a latch signal being outside the range of voltages extending between the low and high values. A reset signal causes the latch signal to be replaced by a comparator reference signal. Further disclosed is a latchable comparator including a comparator and a flip-flop. The comparator has a ramp input, a control input, a first reference input and a second reference input. The flip-flop provides latch signals to each of the first and second reference inputs when its reset input is in the non-reset state and said comparator is generating a first state and maintains the latch signals until a reset signal is received.
    Type: Grant
    Filed: August 19, 1996
    Date of Patent: May 26, 1998
    Assignee: Cherry SemiConductor Corporation
    Inventor: Christopher J. Sanzo
  • Patent number: 5751648
    Abstract: A two stage latch sensing circuit provides high performance at low power in static random access memory (SRAM) devices. The first stage takes the small signal development from the array bitlines which is passed to the sense latch through bit-switches and amplifies it. P-type field effect transistor (PFET) devices are used to drive a precharged high, low-signal swing read data bus. The second stage sense latch amplifies the signal from the read data bus, thereby providing a full level swing to the outputs.
    Type: Grant
    Filed: January 31, 1997
    Date of Patent: May 12, 1998
    Assignee: International Business Machines Corporation
    Inventors: George M. Braceras, Donald A. Evans
  • Patent number: 5751170
    Abstract: A circuit for a low voltage sense amplifier obtains a faster test time in designing a circuit because a conventional sense amplifier adopting voltage 3.3V can be applied to a semiconductor memory device requiring a potential of less than 1.0V, and prevents current leakage at a low threshold voltage by providing source voltage to a sense amplifier of a selected memory cell array in an active mode as well as in a standby mode.
    Type: Grant
    Filed: December 13, 1996
    Date of Patent: May 12, 1998
    Assignee: LG Semicon Co., Ltd.
    Inventor: Hong Beom Pyeon
  • Patent number: 5748020
    Abstract: A high speed capture latch includes differential data inputs, a latch clock input, a boost clock input, a current steering circuit, a switched current source, a latch element and first and second boost current sources. The current steering circuit has first and second differential control terminals which are coupled to the differential data inputs and control current through first and second current paths, respectively. The switched current source is coupled between the current steering circuit and a first voltage supply terminal and has a control terminal coupled to the latch clock input. The latch element is coupled between a second voltage supply terminal and the current steering circuit and provides a latch output. The first boost current source is coupled to the first current path between the latch element and the current steering circuit and has a control terminal coupled to the boost clock input.
    Type: Grant
    Filed: February 2, 1996
    Date of Patent: May 5, 1998
    Assignee: LSI Logic Corporation
    Inventors: Iain Ross Mactaggart, James R. Welch, Alan Fiedler
  • Patent number: 5742552
    Abstract: A semiconductor memory is disclosed having a primary memory array (12) and a dummy column (14) associated therewith that is comprised of a plurality of dummy memory cells (70). The dummy memory cells have a predetermined value stored therein and are sensed with a dummy sense amplifier (18). The dummy sense amplifier (18) has a predetermined offset disposed therein, such that it is in a predetermined state prior to the bit lines separating a sufficient amount to detect the logic state in the dummy memory cell, with an offset disposed therein. This offset prevents the state of the dummy sense amp from being changed until the bit lines are separated by a predetermined value. The primary sense amplifiers associated with the primary memory array (12) are not enabled until the dummy sense amplifier has detected the dummy bit lines as being separating by the predetermined amount.
    Type: Grant
    Filed: October 31, 1996
    Date of Patent: April 21, 1998
    Assignee: Texas Instruments Incorporated
    Inventor: Craig B. Greenberg
  • Patent number: 5742549
    Abstract: To permit effective testing of a sense amplifier circuit, the sense amplifier is designed to be responsive to data stored in a selected memory cell in a controlled test mode. The sense amplifier circuit includes a pull-down circuit having delay circuit to receive and respond to a control signal which indicates whether the sensing circuit is to operate in test mode or normal mode. The sense amplifier circuit also includes an output circuit which is configured and arranged to generate a reference signal corresponding to the data stored in a selected memory cell. To permit sufficient time to test the circuit for correct data values at the output signal, the reference signal is delayed in response to the control signal indicating that the sensing circuit is to operate in test mode.
    Type: Grant
    Filed: March 24, 1997
    Date of Patent: April 21, 1998
    Assignee: Micron Technology, Inc.
    Inventors: Roland Ochoa, Daniel R. Loughmiller
  • Patent number: 5731718
    Abstract: An evaluation and amplifier circuit of the type of a keyed flipflop including at least two first transistors of a given channel type connected in series to each other disposed between first and second signal lines, has a connection from the gates of the first transistors to a respective one of the second and first signal lines. The first two transistors respectively form a first node common to the first two transistors for receiving a first control signal. A series circuit has at least two second transistors of the same channel type as the first transistors being connected in parallel to the first transistors, The gates of the first transistors are further connected with a respective one of the second and first signal lines.
    Type: Grant
    Filed: September 30, 1996
    Date of Patent: March 24, 1998
    Assignee: Siemens Aktiengesellschaft
    Inventor: Johann Rieger
  • Patent number: 5729159
    Abstract: A sensing amplifier that works over a large operating frequency having a plurality of reference inputs, at least one signal input and at least one signal output, where the amplifier comprises a plurality of transistors to internally compare the signal input to the average value of the reference inputs and producing an output based on the comparison. In some cases, the output can be a latched binary signal.
    Type: Grant
    Filed: September 4, 1996
    Date of Patent: March 17, 1998
    Assignee: International Business Machines Corporation
    Inventor: John E. Gersbach
  • Patent number: 5726942
    Abstract: A encoder has a prefetch circuit or a flag data sense circuit built into the priority encoder provided for a CAM block. While a hit signal in the first priority subblock is being encoded, a hit signal in the second priority subblock can be stored in the prefetch circuit. Therefore, the encoding operation is performed without subblock-to-subblock switch time and this makes the encoder best suitable for a large capacity CAM which is required to operate at high speed. Moreover, a semiconductor integrated circuit of the present invention detects the differential current between the current flowing through one signal line and the reference current flowing through the other signal line. Moreover, it can operate as the number detection circuit to detect the number of hit signal in the subblock, and it can operate as the timing control circuit to previously notify the encode termination of the hit signal in the subblock of the encoder described above.
    Type: Grant
    Filed: December 4, 1996
    Date of Patent: March 10, 1998
    Assignee: Kawasaki Steel Corporation
    Inventors: Masato Yoneda, Hiroshi Sasama, Naoki Kanazawa