Having Feedback Patents (Class 327/54)
  • Patent number: 6525572
    Abstract: A sense amplifier circuit has two inputs for connection to complementary bit lines and an output terminal. The circuit comprises control circuitry responsive to control input for selectively tristating the output terminal.
    Type: Grant
    Filed: March 3, 2000
    Date of Patent: February 25, 2003
    Assignee: STMicroelectronics Limited
    Inventor: William Bryan Barnes
  • Patent number: 6518797
    Abstract: In a current mode logic (CML) circuit, a high impedance state is implemented at the output for a bi-directional buffer. The output common mode voltage can be adjusted at the same time, which is particularly useful for a CML off-chip driver.
    Type: Grant
    Filed: December 29, 2000
    Date of Patent: February 11, 2003
    Assignee: International Business Machines Corporation
    Inventor: Jungwook Yang
  • Patent number: 6518798
    Abstract: A sense amplifier that eliminates or substantially attenuates transients at its output node by isolating the output node from the bitline. The sense amplifier incorporates a sense line transistor between the bitline and the output latching circuit in order to strengthen the voltage value at the output node such that it is not affected by the impedance of the bitline. The sense amplifier also consumes less power and is faster because the bitline does not have to be discharged or precharged by the output driver.
    Type: Grant
    Filed: June 7, 2001
    Date of Patent: February 11, 2003
    Assignee: Atmel Corporation
    Inventor: Nicola Telecco
  • Publication number: 20030025532
    Abstract: A sense amplifier that is configurable to operate in two modes in order to control a voltage swing on the sense amplifier output. The sense amplifier has two feedback paths including a first feedback path having a transistor with a fast response time in order to allow the circuit to operate as fast as possible, and a second feedback path for providing voltage swing control. In the first operating mode, the “turbo” mode, both feedback paths are in operation to provide a higher margin of swing control, thus higher sensing speed. In the second operating mode, the “non-turbo” mode, only the first feedback path is in operation which allows for greater stability and a reduction in power consumption.
    Type: Application
    Filed: October 9, 2002
    Publication date: February 6, 2003
    Inventor: Nicola Telecco
  • Patent number: 6507222
    Abstract: An apparatus and method for processing a data input signal with a single ended sense amplifier. The single ended sense amplifier includes a transmission gate circuit and a control circuit coupled between a feedback inverter circuit and an output signal that is fed back to the feedback inverter circuit. An inverter circuit is coupled between an enable signal and the transmission gate and control circuits. During pre-charge operation, the input to the feedback inverter circuit is driven to a first state. The feedback inverter correspondingly drives the input signal to a sensing inverter to a state that is complementary to the input to the feedback inverter circuit, thereby assisting the pre-charge mode and substantially reducing time delay due to the input signal contending with the feedback inverter circuit. One advantage of the present invention is that sense amplifiers can be sized for faster sensing than would other-wise be feasible due to the excessive contention during the pre-charge mode.
    Type: Grant
    Filed: July 23, 2001
    Date of Patent: January 14, 2003
    Assignee: Cirrus Logic, Inc.
    Inventors: Robert A. Jensen, Dimitris C. Pantelakis
  • Patent number: 6504405
    Abstract: A differential amplifier with reduced noise sensitivity enables the bus to operate more efficiently at higher data rates. The amplifier includes an input stage with a pair of adjustable resistive loads that alter the gain of the input stage. A differential output stage receives the output of the input stage and produces a pair of complementary output signals. These output signals are fed back to the adjustable resistive loads so that the gain of the input stage depends upon the levels of the output signals. The feedback is positive, so the voltage transfer characteristic of the inventive amplifier has different input thresholds for positive- and negative-going voltage signals.
    Type: Grant
    Filed: December 6, 2001
    Date of Patent: January 7, 2003
    Assignee: Rambus Inc.
    Inventors: Huy M. Nguyen, Benedict C. Lau
  • Publication number: 20020186051
    Abstract: A sense amplifier that eliminates or substantially attenuates transients at its output node by isolating the output node from the bitline. The sense amplifier incorporates a sense line transistor between the bitline and the output latching circuit in order to strengthen the voltage value at the output node such that it is not affected by the impedance of the bitline. The sense amplifier also consumes less power and is faster because the bitline does not have to be discharged or precharged by the output driver.
    Type: Application
    Filed: June 7, 2001
    Publication date: December 12, 2002
    Inventor: Nicola Telecco
  • Patent number: 6492844
    Abstract: A sense amplifier having a sampling circuit to sample the amplifier input signal; a reference node storing a reference signal corresponding to the input signal; and a timing circuit activating the sampling circuit for a predetermined interval, and admitting the reference signal to the reference node. The sense amplifier also can include a pump capacitor substantially maintaining a value of the reference signal; and a gain circuit coupled with the reference node and disposed to adaptively adjust gain of an output signal produced by the sense amplifier. The sense amplifier can be a single-ended sense amplifier.
    Type: Grant
    Filed: February 2, 2001
    Date of Patent: December 10, 2002
    Assignee: Broadcom Corporation
    Inventors: Esin Terzioglu, Morteza Cyrus Afghahi
  • Patent number: 6476645
    Abstract: A method and apparatus for mitigating the history effect in silicon-on-insulator (SOI)-based circuitry, e.g., data interface circuitry operable as a single-ended off-chip signal receiver in a VLSI component such as a microprocessor. A sense amplifier (sense amp) latch circuit arrangement includes a sense amp operable to sense data and a latch operable to hold the sensed data. When data is available, the sense amp generates a pair of complementary data signals responsive to a control signal used for alternating the sense amp's operation between an evaluation phase and an equilibration (i.e., pre-charge) phase. A feedback circuit portion is operable to modify the control signal's logic state within a clock phase associated with one of the two complementary clocks provided to the interface circuitry. Since the equilibration phase is entered combinationally off the evaluation phase, both evaluation and equilibration can be triggered from the same clock edge.
    Type: Grant
    Filed: August 10, 2001
    Date of Patent: November 5, 2002
    Assignee: Hewlett-Packard Company
    Inventor: Philip L. Barnes
  • Patent number: 6466500
    Abstract: An amplifier circuit configuration includes a data line for transmitting a data signal. The data line is connected to a data signal input of an amplifier by way of a switching device. The amplifier includes a control circuit for controlling an input resistance of the amplifier with a terminal for a control signal. The terminal for the control signal of the control circuit is connected, parallel to the switching device, to the data line. As a consequence, a switching device, which is connected between the data line and the amplifier, has only little influence on the dynamic response when reading out a data signal.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: October 15, 2002
    Assignee: Infineon Technologies AG
    Inventors: Bernhard Wicht, Steffen Paul
  • Patent number: 6456170
    Abstract: The inverter functioning as a comparator, dummy inverter having the same electric characteristics as the inverter, and control circuit are provided. Vth detecting input voltage output from the control circuit is input into the dummy inverter, Vth detecting output voltage output from the dummy inverter is input into the control circuit, and the threshold voltage of the dummy inverter is detected. The threshold voltage of the inverter is controlled by controlling the back gate voltages of the MOS transistors of the dummy inverter and the inverter in such a manner that the threshold voltage of the dummy inverter coincide with an external reference voltage.
    Type: Grant
    Filed: March 30, 2000
    Date of Patent: September 24, 2002
    Assignee: Fujitsu Limited
    Inventors: Yuji Segawa, Masaru Otsuka, Osamu Kikuchi, Akira Haga, Yoshinori Yoshikawa
  • Patent number: 6437612
    Abstract: A buffer amplifier comprising a source follower-common drain circuit with a feedback path from the output of the drain follower to the input gate of the source follower. The feedback circuit is designed such that the output of the drain follower can be guaranteed to be at a voltage midway between the positive and the negative voltage supply of the circuit. This is the optimum operating point since it allows the largest signal swing. A small transconductance is realized by biasing the transistors of the feedback amplifier with very low currents; preferably by operating them in their weak inversion region. Feedback through the feedback amplifier is only present at DC (direct current) and at very low frequencies. This stabilizes the DC voltage at the drain of the common drain transistor, which, via an output capacitor, is also the output of the buffer amplifier.
    Type: Grant
    Filed: November 28, 2001
    Date of Patent: August 20, 2002
    Assignee: Institute of Microelectronics
    Inventors: Uday Dasgupta, Wooi Gan Teoh
  • Patent number: 6411550
    Abstract: To reduce current consumption in a sense amplifier circuit in a semiconductor integrated-circuit device, in particular, in a semiconductor integrated-circuit having a non-volatile memory as a memory element thereof. A Switching element for cutting off a direct current at the end of data reading from a memory is arranged in a path through which the direct current flows. In this way, the switching element cuts off the direct current at the moment of completion of the data reading from the memory, thereby substantially reducing current consumption.
    Type: Grant
    Filed: July 31, 2000
    Date of Patent: June 25, 2002
    Assignee: Seiko Epson Corporation
    Inventor: Hiroaki Nasu
  • Patent number: 6384637
    Abstract: A differential amplifier with reduced noise sensitivity enables the bus to operate more efficiently at higher data rates. The amplifier includes an input stage with a pair of adjustable resistive loads that alter the gain of the input stage. A differential output stage receives the output of the input stage and produces a pair of complementary output signals. These output signals are fed back to the adjustable resistive loads so that the gain of the input stage depends upon the levels of the output signals. The feedback is positive, so the voltage transfer characteristic of the inventive amplifier has different input thresholds for positive- and negative-going voltage signals.
    Type: Grant
    Filed: June 6, 2000
    Date of Patent: May 7, 2002
    Assignee: Rambus
    Inventors: Huy M. Nguyen, Benedict C. Lau
  • Publication number: 20020003441
    Abstract: An operational amplifier (opamp) [74] coupled in a negative-feedback configuration [82][84] comprising a driving opamp [76]; a linear controller [78]; and a mechanism [80] controlling the driving opamp's [76] offset. A voltage signal Vin provided by the feedback network [82][84] characterizes all errors caused by the driving opamp [76]. The controller [78] monitors this voltage and minimizes the signal-band spectral components thereof by inducing an offset in the driving opamp [76]. The offset control mechanism [80] has approximately constant gain and only little phase delay in the signal band. The controller [78] may be a linear high-order Chebychev filter providing substantial gain in a wide frequency range, thereby efficiently suppressing all signal-band errors, including noise, harmonic distortion, and slew-rate errors, caused by the driving opamp [76].
    Type: Application
    Filed: January 12, 2001
    Publication date: January 10, 2002
    Inventor: Jesper Steensgaard-Madsen
  • Patent number: 6307405
    Abstract: Current sense amplifiers with hysteresis are provided which conserve scarce chip surface area yet still provide fast response times in a low power CMOS environment. A first embodiment includes a first amplifier and a second amplifier which are electrically coupled. Each amplifier includes a first transistor of a first conductivity type and a second transistor of a second conductivity type, where the first and second transistors are coupled at a drain region. A signal input node is coupled to a source region of the first transistor in each amplifier. A signal output node is coupled to the drain region of the first and the second transistors in the second amplifier. The signal output node is further coupled to a gate of a third transistor in order to introduce hysteresis into the current sense amplifier. Integrated circuits, electrical systems, methods of operation and methods of forming the novel current sense amplifier are similarly included.
    Type: Grant
    Filed: April 27, 1999
    Date of Patent: October 23, 2001
    Assignee: Micron Technology, Inc.
    Inventors: Leonard Forbes, Eugene H. Cloud
  • Patent number: 6292032
    Abstract: A high impedance circuit capable of operating at a low voltage without narrowing the dynamic range is provided, which includes a first and a second transistors forming differential-pair type circuit, a third and fourth transistors, a pair of collector resistance elements, a resistance element and a pair of current source circuits. The third and the fourth transistors serve as emitter follower circuits which also functions as a DC shift with respect to the differential-pair type circuit, as well as buffer circuits for heightening an input impedance of the first and the second transistors looked from the base side of the third and the fourth transistors. The current flowing in the resistance element is made current-fedback with respect to the resistance elements by the third and the fourth transistors. The input impedance is determined as Z1=V1/ i3=(R1×R2)/(R1−R2), and when R1=R2, the high impedance circuit becomes infinite impedance.
    Type: Grant
    Filed: May 12, 2000
    Date of Patent: September 18, 2001
    Assignee: Sony Corporation
    Inventors: Atsushi Hirabayashi, Kosuke Fujita, Kenji Komori, Norihiro Murayama
  • Patent number: 6286127
    Abstract: A control circuit is provided which includes a single programmable terminal for controlling a plurality of modes, functions or parameters in a programmable circuit with a minimum of program elements connected to the single programmable terminal. The program elements may illustratively be resistors, capacitors, inductors or other circuit components. In a first mode, for example, two program elements control a signal generating function in the programmable circuit. In a second mode, a voltage provided internally forces a condition at the programmable terminal to control another signal generating function. In both first and second modes, the values of the program elements, selectable by the user, also determine the particular frequencies of the respective generated signals. In a third mode, the signals generated in the first and second modes are compared to provide a control function.
    Type: Grant
    Filed: February 6, 1998
    Date of Patent: September 4, 2001
    Assignee: Texas Instruments Incorporated
    Inventors: Ken Richard King, Mark Charles Fischer
  • Patent number: 6259280
    Abstract: A class AB amplifier (400) is disclosed, having a first input node (402), a second input node (404), and an output node (406). A push-pull input stage (412) includes cross-coupled pairs of transistors, which form a charge current path and a discharge current path. When the voltage at the first input node (402) is greater than the voltage at the second input node (406), the amount of current drawn in the charge current path increases, and the amount of current drawn in the discharge current path decreases. When the voltage at the first input node (402) is less than the voltage at the second input node (404), the amount of current in the charge current path decreases while the amount of current in the discharge path increases. A first and fourth current mirror (422 and 428) are coupled to the charge current path, and a second and third current mirror (424 and 426) are coupled to the discharge current path.
    Type: Grant
    Filed: September 25, 1998
    Date of Patent: July 10, 2001
    Assignee: Texas Instruments Incorporated
    Inventor: Jeffrey E. Koelling
  • Publication number: 20010002110
    Abstract: Novel current sense amplifiers with hysteresis are provided which conserve scarce chip surface area yet still provide fast response times in a low power CMOS environment. A first embodiment includes a first amplifier and a second amplifier which are electrically coupled. Each amplifier includes a first transistor of a first conductivity type and a second transistor of a second conductivity type, where the first and second transistors are coupled at a drain region. A signal input node is coupled to a source region of the first transistor in each amplifier. A signal output node is coupled to the drain region of the first and the second transistor in the second amplifier. The signal output node is further coupled to a gate of a third transistor in order to introduce hysteresis into the current sense amplifier.
    Type: Application
    Filed: April 27, 1999
    Publication date: May 31, 2001
    Inventors: LEONARD FORBES, EUGENE H. CLOUD
  • Patent number: 6133763
    Abstract: A high impedance circuit capable of operating at a low voltage without narrowing the dynamic range is provided, which includes a first and a second transistors forming differential-pair type circuit, a third and fourth transistors, a pair of collector resistance elements, a resistance element and a pair of current source circuits. The third and the fourth transistors serve as emitter follower circuits which also functions as a DC shift with respect to the differential-pair type circuit, as well as buffer circuits for heightening an input impedance of the first and the second transistors looked from the base side of the third and the fourth transistors. The current flowing in the resistance element is made current-fedback with respect to the resistance elements by the third and the fourth transistors. The input impedance is determined as Z1=V1/i3=(R1.times.R2)/(R1-R2), and when R1=R2, the high impedance circuit becomes infinite impedance.
    Type: Grant
    Filed: September 16, 1998
    Date of Patent: October 17, 2000
    Assignee: Sony Corporation
    Inventors: Atsushi Hirabayashi, Kosuke Fujita, Kenji Komori, Norihiro Murayama
  • Patent number: 6133778
    Abstract: An anti-fuse programming circuit comprising an operation switching part for precharging the anti-fuse programming circuit with a half voltage to operate it, an anti-fuse connected to the operation switching part, the anti-fuse being subjected to a dielectric breakdown when it is supplied with an overcurrent, a sense signal input part for inputting a sense signal to verify a programmed state of the anti-fuse, a breakdown voltage supply part for supplying a source voltage for the dielectric breakdown of the anti-fuse, an output part for outputting a signal indicative of the programmed state of the anti-fuse in response to the sense signal inputted by the sense signal input part, a feedback part for feeding back the output signal from the output part strongly at low power and high speed, a current blocking part for blocking a current path from the breakdown voltage supply part to the anti-fuse in response to a control signal from the feedback part, a reverse current prevention part for blocking the flow of curre
    Type: Grant
    Filed: June 29, 1999
    Date of Patent: October 17, 2000
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventors: Young Hee Kim, Kie Bong Ku
  • Patent number: 6121823
    Abstract: An electrical circuit provides a variety of stable and reliable bias voltages to accommodate the bias requirements of various sensor types. The electrical circuit comprises a programmable analog circuit capable of maintaining a plurality of programmable threshold voltages and producing a plurality of intermediary voltages. Such voltages act as an input to a differential amplifier that outputs a bias voltage within a range consistent with said programmable threshold voltages. The bias voltage is further conditioned by a conditioning amplifier that further stabilizes the bias voltage to an attached sensor.
    Type: Grant
    Filed: March 17, 1999
    Date of Patent: September 19, 2000
    Assignee: Analytical Technology, Inc.
    Inventor: Stephen D. Summerfield
  • Patent number: 6108258
    Abstract: A sense amplifier can be used with a high-speed IC memory device, which sense amplifier can help reduce the sensing latency during read operations to the memory device so as to allow fast access speed to the memory device. The sense amplifier includes a first-stage circuit, coupled to the bit lines of the memory device, for amplifying the differential data signal on the bit lines. Furthermore, a second-stage circuit has an input side coupled to receive the output signal from the first-stage circuit and an output side coupled to the bit lines, and is used for amplifying the output signal from the first-stage circuit and feeding the amplified signal back to the bit lines. The first-stage circuit and the second-stage circuit in combination constitute a positive feedback amplification loop coupled to the bit lines for amplifying the differential data signal on the bit lines to a detectable level.
    Type: Grant
    Filed: August 19, 1999
    Date of Patent: August 22, 2000
    Assignee: United Integrated Circuits Corp.
    Inventors: Juei-Lung Chen, Shin-Huang Huang, Hsin-Pang Lu
  • Patent number: 6107839
    Abstract: The sense amplifier of the present invention senses the logic level of a digital data element that is conveyed using a low voltage swing signal. That sensing operation occurs relatively soon after the logic level of the data element begins to be established at the input of the sense amplifier. Such a sense amplifier is referred to as having increased sensitivity due to an improved common mode rejection ratio. The common mode rejection ratio is improved by turning-on a pair of evaluate transistors in a successive manner. The sense amplifier includes a pair of discharge paths for allowing a charge, stored on associated internal signals, to be discharged at a given rate that is proportional to voltage levels of the associated data signals. Those data signals are isolated from the discharge paths such that the associated logic levels are not affected by the above mentioned discharge operation.
    Type: Grant
    Filed: February 1, 1999
    Date of Patent: August 22, 2000
    Assignee: Compaq Computer Corporation
    Inventors: Jeff L. Chu, Daniel W. Bailey, Jason F. Cantin
  • Patent number: 6097653
    Abstract: An overdriving control circuit includes a comparator for receiving a sense amplifier enable signal and comparing a voltage of bit line or bit bar line with a reference voltage, and a sense amplifier driving unit for logically combining the sense amplifier enable signal and an output signal of the comparator and outputting a control signal of a switch which selectively supplies an internal voltage and an external voltage. The circuit senses a variation of the external voltage or a bouncing of source voltage and controls the overdriving region, thereby obtaining a sufficient overdriving region and accelerating the operation of a sense amplifier.
    Type: Grant
    Filed: October 1, 1998
    Date of Patent: August 1, 2000
    Assignee: LG Semicon Co., Ltd.
    Inventor: San-Ha Park
  • Patent number: 6072339
    Abstract: A current sensing circuit with high input impedance comprises a first transconductance amplifier connected across the terminals of a resistor, through which a current to be measured flows. A voltage amplifier is cascade-connected to the first transconductance amplifier. A second transconductance amplifier is feedback connected between an output of the voltage amplifier and a virtual ground node of the voltage amplifier. A ratio between the output voltage of the voltage amplifier and the voltage across the resistor are equal, in absolute value, to a ratio of the transconductances of the first and second transconductance amplifiers.
    Type: Grant
    Filed: November 4, 1998
    Date of Patent: June 6, 2000
    Assignee: STMicroelectronics S.r.l
    Inventor: Luca Bertolini
  • Patent number: 6064613
    Abstract: A fast CMOS sense amplifier for semiconductor memories is disclosed. The memory sense amplifier configuration is comprised of differential pre-sense amplifier stage and a sense amplifier second stage. The pre-sense amplifier stage is composed of two sections with feedback between the sections which reduces the output swing by means of a clamping action, therefore improving output switching recovery time in response to differential input. The feedback between the sections is provided by cross connecting the sub outputs of each section to the gate of a clamping transistor at each section. The reduced recovery time produces reduced delay at the output which speeds up the operation of the sense amplifier. Additionally, the clamping devices have the effect of reducing the average DC current in the pre-sense amplifier.
    Type: Grant
    Filed: December 28, 1998
    Date of Patent: May 16, 2000
    Assignee: Etron Technology, Inc.
    Inventor: Gyh-Bin Wang
  • Patent number: 6064614
    Abstract: A finite impulse response filter uses rotating tap weights that are connected in turn to a succession of sample/hold (S/H) cells in each of which is held a separate successive sample of an analog balanced signal being filtered for an interval long enough to tap to each tap weight in one rotation. Each of the S/H cells is a switched-current memory cell and includes a primary negative feedback transconductance differential amplifier and a primary pair of storage capacitors and a secondary positive feedback transconductance differential amplifier and a secondary pair of storage capacitors. Charge injection errors created in each primary amplifier are replicated in an associated secondary amplifier and used to cancel these errors to provide higher fidelity samples for summing for forming the output of the filter. The tap weights are provided by binary-ratioed resistors provided by transistors of binary-ratioed transconductances.
    Type: Grant
    Filed: May 13, 1999
    Date of Patent: May 16, 2000
    Assignee: Lucent Technologies
    Inventor: John M. Khoury
  • Patent number: 6061192
    Abstract: A system for providing feedback to a selected read head in a multi-head disk drive includes first and second feedback circuits is disclosed. A first feedback circuit 200 provides for correction of the output of the selected read head during normal operation. The first feedback circuit 200 produces a differential output current proportional to an offset voltage detected on the read head output nodes 103 and 104. This differential output current charges external capacitor 190. The voltage across capacitor 190 is supplied to voltage inputs of the selected read head as a feedback voltage. When the feedback voltage reaches the desired level, nodes 103 and is 104 equalize, as do the output currents of the first feedback circuit 200. The second feedback circuit 300 provides for quick recovery of the system after a change in read heads.
    Type: Grant
    Filed: August 18, 1997
    Date of Patent: May 9, 2000
    Assignee: Texas Instruments Incorporated
    Inventor: Hisao Ogiwara
  • Patent number: 6054879
    Abstract: A sense amplifier that includes a sensing circuit, a first feedback circuit, and an output buffer. The first feedback circuit is coupled to an output of the sensing circuit and is configured in a feedback arrangement with the output buffer. The output of the sensing circuit provides an output signal having a first slew rate as the output signal transitions from a first logic state to a second logic state. The first feedback circuit may increase the slew rate of the output signal. The sense amplifier may also include a second feedback circuit coupled to the output of the sensing circuit and configured in a feedback arrangement with the output buffer. The second feedback circuit may increase a second slew rate of the output signal as the output signal transitions from the second logic state to the first logic state. The sense amplifier may be a current sense amplifier that may be used to sense the amount of current flowing through a nonvolatile memory circuit.
    Type: Grant
    Filed: December 8, 1997
    Date of Patent: April 25, 2000
    Assignee: Cypress Semiconductor Corp.
    Inventor: Anita X. Meng
  • 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: 6009032
    Abstract: A cell-sensing unit is applied to a memory device having a cell associated operably with a complementary pair of bit lines and a word line. The cell-sensing unit includes a current sense amplifier having a first input side adapted to be connected to the bit lines, and a first output side, and a voltage amplifier having a second input side connected to the first output side of the current sense amplifier, and a second output side. The current sense amplifier is capable of magnifying a difference between currents flowing through the bit lines during a read cycle of the cell, and generates a corresponding voltage difference at the first output side. The voltage difference is received by the voltage amplifier at the second input side, and has a magnitude sufficient to enable the voltage amplifier to generate an output signal at the second output side corresponding to data stored in the cell.
    Type: Grant
    Filed: June 4, 1999
    Date of Patent: December 28, 1999
    Assignee: Silicon Integrated Systems Corp.
    Inventors: Hsiu-Ping Lin, Hsing-Yi Chen
  • Patent number: 5973955
    Abstract: A pipelined dual port integrated circuit memory (20) includes an array (30) of static random access memory (SRAM) cells. A control circuit (32) controls access to the memory cells, where substantially simultaneous requests for access are serviced sequentially within a single cycle of a clock signal of a data processor that is accessing the memory (20). An address collision detector (110) uses both a differential amplifier (360) included within a D-flip-flop circuit (114) and a reference voltage provided by a reference voltage circuit (365) to compare addresses provided to the two ports, and generates a match signal that is used for determining which of the two ports are serviced first, independent of which port is read from, or written to. Because dual port functionality is obtained using a single port SRAM array (30), the memory (20) may be manufactured using relatively less integrated circuit surface area, and therefore at a lower cost.
    Type: Grant
    Filed: February 2, 1998
    Date of Patent: October 26, 1999
    Assignee: Motorola, Inc.
    Inventors: Scott G. Nogle, Alan S. Roth, Shuang L. Ho
  • Patent number: 5920208
    Abstract: A power down circuit and method of a sense amplifier for a semiconductor memory device prevents undesirable power consumption by detecting when sensing is completed in the sense amplifier and inhibiting a power supply current flow to the sense amplifier after the detection. The power down circuit includes a data comparator for comparing data outputs from a sense amplifier to inhibit the supply current of the sense amplifier by detecting the sensing operation completion in the sense amplifier, a data latch unit for latching the comparison result from the data comparator, a data enable/reset unit for outputting or resetting the latched comparison result, and a power down unit for turning on or off the sense amplifier circuit based on the comparison result outputted from the data enable/reset unit.
    Type: Grant
    Filed: October 14, 1997
    Date of Patent: July 6, 1999
    Assignee: LG Semicon Co., Ltd.
    Inventor: Yeon-Jun Park
  • Patent number: 5914526
    Abstract: A semiconductor device incorporating an operational amplifier having two input terminals. The device includes a semiconductor substrate, an insulation film formed on the semiconductor substrate and an element having first and second electrodes formed on the insulation film. The first and second electrodes are respectively connected to the two input terminals of the electronic circuit. The first electrode, the insulation film and the semiconductor substrate form a parasitic capacitor. The device also includes a third electrode formed on the insulation film. The third electrode is connected to the second electrode of the element.
    Type: Grant
    Filed: December 12, 1996
    Date of Patent: June 22, 1999
    Assignee: Kabushiki Kaisha Tokai Rika Denki Seisakusho
    Inventor: Hitoshi Iwata
  • Patent number: 5872465
    Abstract: In a sense amplifier including an amplifier circuit for amplifying a difference in potential between data lines, an amplifier circuit activating circuit for receiving a sense start signal to activate the amplifier circuit and receiving a sense end signal to deactivate said amplifier circuit, a first sense detecting circuit for determining whether or not the amplifier circuit is activated in accordance with a first output voltage thereof and generating a first sense detection signal, a second sense detecting circuit for determining whether or not the amplifier circuit is activated in accordance with a second output voltage thereof and generating a second sense detection signal, and a sense end signal generating circuit for receiving at least one of the first and second sense detection signals and generating the sense end signal when a predetermined time has passed after at least one of the first and second sense detection signals is received, a masking circuit is connected between the first and second sense de
    Type: Grant
    Filed: August 27, 1997
    Date of Patent: February 16, 1999
    Assignee: NEC Corporation
    Inventor: Toshio Saitoh
  • Patent number: 5847591
    Abstract: The voltage detection and control circuit includes a voltage detect circuit having an associated switch point greater than a first predetermined voltage, with the voltage detect circuit being responsive to an input voltage greater than the first predetermined voltage for generating an activation signal; and a clamp control circuit, responsive to the activation signal, for clamping an operating voltage to a second predetermined voltage. The second predetermined voltage may be substantially equal to the first predetermined voltage. A spike filter may be included for suppressing spikes in the activation signal. A clamp stage control circuit is provided for suppressing oscillations in the second predetermined voltage. At least one clamp stage, which may include a delay device, provides the operating voltage to a corresponding circuit component as well as reducing current peaks in the corresponding circuit component.
    Type: Grant
    Filed: March 31, 1997
    Date of Patent: December 8, 1998
    Assignee: Siemens Aktiengesellschaft
    Inventor: Josef T. Schnell
  • Patent number: 5834952
    Abstract: A biasing circuit for a two terminal sensing element has two separate biasing elements. Both biasing elements are controlled by a transconductance feedback circuit that controls feedback currents based upon a voltage associated with the sensing element. Both biasing elements also receive an activation value from an activation circuit. The activation value activates both biasing elements directly, without using the feedback loop.
    Type: Grant
    Filed: October 10, 1996
    Date of Patent: November 10, 1998
    Assignee: VTC Inc.
    Inventor: Tuan V. Ngo
  • Patent number: 5811993
    Abstract: A FET band-gap reference generating circuit having a two-branch differential amplifier with a saturation state FETs for equal branch current, independent of power supply voltage, with a feedback connection to a reference FET in one branch, for driving the steady state output to the threshold voltage of the reference FET, also independent of the power supply voltage. A multistage circuit connects a divided down output of a first FET band-gap reference generating circuit to a current bias terminal of similar second FET based differential amplifier so that the steady state output of the second amplifier is equal to the sum of the divided down output and a threshold voltage of a second reference FET in the second amplifier.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: September 22, 1998
    Assignee: International Business Machines Corporation
    Inventors: Robert Heath Dennard, Thekkemadathil Velayudhan Rajeevakumar
  • Patent number: 5804866
    Abstract: A method and device for maintaining junction isolation between a second region that is normally clamped at a reference potential, contained within a first region of an opposite type of conductivity whose potential is subject to large inertial swings. The junction is ensured even when the potential of the first region moves toward and beyond the reference potential to which the second region is clamped, by connecting the second region to the reference potential by a switch, and causing the switch to open which places the second region in a floating state, leaving it free to track the potential excursion of the first region. The switch is closed after the potential of the first region has returned to a normal value. A comparator senses a shift of the potential of the second region from the reference potential to which it is clamped. The shift is dynamically induced by the capacitive coupling of the two regions, and triggers off the clamping switch.
    Type: Grant
    Filed: March 21, 1996
    Date of Patent: September 8, 1998
    Assignee: Consorzio per la Ricerca sulla Microelettronica nel Mezzogiorno
    Inventors: Natale Aiello, Vito Graziano
  • Patent number: 5796281
    Abstract: In an interface for an input signal with a small amplitude and a high bit rate, the output voltage of a receiver can become more indeterminate when the input signal voltage at the receiving end of a signal transmission line becomes equal to a reference voltage V.sub.ref. In the input buffer circuit of the CMOS current mirror type, a transistor Q.sub.2 is connected in parallel with another transistor Q.sub.1, where the conductivity types of both the transistors are the same and a reference voltage V.sub.ref is applied to the gate electrode of the transistor Q.sub.1. The transistor Q.sub.2 endows the input buffer circuit with a hysteresis characteristic, and the output power N1 of the input buffer circuit is supplied to the gate electrode of the transistor Q.sub.2.
    Type: Grant
    Filed: July 23, 1996
    Date of Patent: August 18, 1998
    Assignee: NEC Corporation
    Inventors: Takanori Saeki, Yukio Fukuzo
  • Patent number: 5786723
    Abstract: The present invention comprises a cascode circuit of the type having a first and second FET in a first leg and a third and fourth FET in a second leg comprising. The first and third FETs are switched between an on state and an off state substantially in tandem in response to a level change in an input signal to the cascode circuit. The second and fourth FETs are switched between an on state and an off state substantially in tandem in response to a level change in the input signal and substantially complimentary to the switching of said first and third FETS. A biasing signal is applied to a control electrode of the first FET responsive to transition of the input signal from a first level to a second level. A biasing signal is also applied to a control electrode of the third FET responsive to transition of the input signal from the second level to the first level.
    Type: Grant
    Filed: July 1, 1996
    Date of Patent: July 28, 1998
    Assignee: Samsung Electronics, Co, Ltd.
    Inventor: Jong-Sun Kim
  • Patent number: 5770953
    Abstract: A destructive read sense-amp (typically used in SRAM) includes circuitry for disabling its amplifier circuitry in response to a predetermined logic level appearing at its output, circuitry for preserving the predetermined logic level appearing at its output, and circuitry for modifying data carried on data transmission lines connected to its differential inputs. The output preserving means and data modifying circuitry are only enabled while the sense-amp's amplifier circuitry is disabled. In a preferred implementation, the destructive read sense-amp writes a logic "0" into a memory cell upon reading a logic "1" from the same memory cell. The reading and writing of data occurs within a single read cycle.
    Type: Grant
    Filed: January 17, 1997
    Date of Patent: June 23, 1998
    Assignee: Hewlett-Packard Co.
    Inventor: James G. Eldredge
  • Patent number: 5751178
    Abstract: The electronic circuit (100) of the invention receives first signals DATA (170) having logical "1" at high (VCCH) or low (VCCL) levels and logical "0" at reference level (ZERO) and generates second signals OUT (186) between high level (VCCH) and reference level (ZERO) without changing the information. The circuit comprises a first switch (161) and a second switch (161) serially coupled together to a common output node (103). The first switch (162) is controlled by a control signal (CTRL) derived from DATA, OUT, or optionally from a clock signal CLK. The first switch (161) is switched off before the second switch (162) is switched off. Contention (conducting at the same time) is thereby avoided and the first switch (161) and the second switch (162) can be implemented by substantially equal-sized components.
    Type: Grant
    Filed: December 5, 1996
    Date of Patent: May 12, 1998
    Assignee: Motorola, Inc.
    Inventors: Joseph Shor, Eytan Engel, Natan Baron
  • Patent number: 5748534
    Abstract: To read the threshold voltage of a transistor such as a floating gate transistor in an analog or multi-level memory cell, the transistor is connected in a feedback loop which contains a differential amplifier having an output terminal and an input terminal respectively connected to the gate and a node (source or drain) of the transistor. A reference voltage is asserted to a second input terminal of the differential amplifier. A load provides a current which charges the node, and the differential amplifier adjusts the gate voltage of the memory cell to an equilibrium value where current through the transistor is equal to current through the reference cell. The equilibrium value of the gate voltage depends on and indicates the threshold voltage of the transistor. In one embodiment of the invention, the load is a current source which mirrors a current through a reference cell that is structurally identical to the transistor, and the drain of the reference cell provides the reference voltage to the amplifier.
    Type: Grant
    Filed: March 26, 1996
    Date of Patent: May 5, 1998
    Assignee: Invox Technology
    Inventors: Frank M. Dunlap, Hock C. So, Sau C. Wong
  • Patent number: 5729160
    Abstract: A device and method for self-timed, temporary disabling or latching of an electric circuit. A first portion of the circuit has sensing means for sensing a change in the value of an output signal of a second circuit portion corresponding to a change between logic states. The first circuit portion also includes immobilizing means responsive to the sensing means for temporarily disabling or latching the second circuit portion. The immobilizing means functions after such a change in logic state has occurred and, in addition, when the output signal of the second circuit portion has acquired a value corresponding to a predetermined logic state. Disabling occurs when the immobilizing means turns off a switch of the second portion. Latching occurs when the immobilizing means activates latch means of the second portion, thereby fixing voltage level(s) and corresponding logic state(s).
    Type: Grant
    Filed: July 20, 1994
    Date of Patent: March 17, 1998
    Assignee: Mosaid Technologies Incorporated
    Inventor: Graham A. Allan
  • Patent number: 5698998
    Abstract: Small voltage changes on a highly capacitive signal are sensed rapidly by placing a shielding impedance between the signal to be sensed and the input to a regenerative sense circuit. A regenerative sense circuit has a sense amplifier which controls a switching means that is connected to the input to the sense amplifier. When the output of the sense amplifier reaches a threshold value, it turns the switching means on. This switching means increases the rate of change on the input to the sense amplifier which causes the switching means to turn on even more. The input and output of the sense amplifier are able to switch more rapidly because the shielding impedance allows the switching means to change the state of the input to the sense amplifier without having to completely change the voltage level on the highly capacitive input signal. A small voltage difference between two signals is sensed by two cross-coupled, actively loaded, NMOS inverters.
    Type: Grant
    Filed: April 12, 1996
    Date of Patent: December 16, 1997
    Assignee: Hewlett-Packard Co.
    Inventor: Paul R. Bodenstab
  • Patent number: 5696724
    Abstract: A sense amplifier comprising a data refresh amplifier for supplying voltages to true and complementary bit lines in response to a first control signal to amplify true and complementary data on the true and complementary bit lines, respectively, a first transistor for amplifying current of the true data on the true bit line in response to a second control signal and transferring the amplified true data to a true input/output line, a second transistor for amplifying current of the complementary data on the complementary bit line in response to the second control signal and transferring the amplified complementary data to a complementary input/output line, a first switch for selectively forming a current path between the true input/output line and the true bit line, and a second switch for selectively forming a current path between the complementary input/output line and the complementary bit line.
    Type: Grant
    Filed: December 16, 1996
    Date of Patent: December 9, 1997
    Assignee: Hyundai Electronics Industries Co., Ltd.
    Inventors: Yo Hwan Koh, Chan Kwang Park, Jeung Won Suh
  • Patent number: 5663915
    Abstract: An improved current sensing differential amplifier which includes a separate p-channel bias stage to reduce the minimum operating voltage VCC of the circuit. The separate p-channel bias stage is also used to pre-bias a driver stage to more quickly generate differential output currents. Finally, the improved current sensing differential amplifier also includes negative feedback transistors to improve the recovery time of the circuit.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: September 2, 1997
    Assignees: United Memories, Inc., Nippon Steel Semiconductor Corporation
    Inventor: Kenneth J. Mobley