Ttl To/from Cmos Patents (Class 326/71)
  • Patent number: 11139323
    Abstract: Provided is a digital circuit (30) that comprises: a switching circuit (31) having first transistors (32, 33) supplied with power supply potentials (VDD, VSS); correcting circuits (34, 36) connected between an input terminal (IN) inputted with an input signal and control terminals (gates) of the first transistors; capacitors (C2, C3) connected between the control terminals and the input terminal; diode-connected second transistors (35, 37) that are provided between nodes (N5, N6) between the capacitors and the control terminals and the power supply potentials and have the substantially sanle threshold voltage as the first transistors; and switches (SW2, SW3) connected in series with the second transistors.
    Type: Grant
    Filed: November 15, 2019
    Date of Patent: October 5, 2021
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Hajime Kimura
  • Patent number: 10840974
    Abstract: An integrated-circuit output driver generates, in response to an input signal constrained to a first voltage range, a control signal at one of two voltage levels according to a data bit conveyed in the input signal, the two voltages levels defining upper and lower levels of a second voltage range substantially larger than the first voltage range. The output driver generates an output-drive signal constrained to a third voltage range according to the one of the two voltage levels of the control signal, the third voltage range being substantially smaller than the second voltage range.
    Type: Grant
    Filed: April 1, 2019
    Date of Patent: November 17, 2020
    Assignee: Rambus Inc.
    Inventors: Frederick A. Ware, Carl W. Werner
  • Patent number: 10277181
    Abstract: To reduce power consumption and perform high-speed switching in boosting a voltage to a desired voltage. A semiconductor device includes a first buffer circuit, a level-shift circuit, and a second buffer circuit. The first buffer circuit includes a tri-state buffer circuit. The tri-state buffer circuit has a function of making each of an output of an input signal and an output of an inverted input signal into a resting state in response to a standby signal. The level-shift circuit includes a current mirror circuit, a differential amplifier circuit, and a switch circuit. The differential amplifier circuit has a function of controlling a current flowing through the current mirror circuit using the input signal and the inverted input signal as differential signals. The switch circuit has a function of making a current flowing through the differential amplifier circuit into a resting state in response to the standby signal.
    Type: Grant
    Filed: August 24, 2017
    Date of Patent: April 30, 2019
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Hiroki Inoue
  • Patent number: 9964832
    Abstract: An electronic driver circuit for use with a modulator such as a segmented Mach-Zehnder Modulator (MZM) is provided. The electronic driver circuit includes a first delay buffer implemented as a first complementary metal-oxide-semiconductor (CMOS) inverter and a second delay buffer implemented as a second CMOS inverter. The second CMOS inverter follows the first CMOS inverter and has a second gate width smaller than a first gate width of the first CMOS inverter. The first CMOS inverter is configured to produce a first delayed electrical signal from a received electrical signal and the second CMOS inverter is configured to produce a second delayed electrical signal from the first delayed electrical signal produced by the first CMOS inverter.
    Type: Grant
    Filed: May 28, 2015
    Date of Patent: May 8, 2018
    Assignee: Futurewei Technologies, Inc.
    Inventors: Morgan Chen, Yifan Gu, Hungyi Lee, Liang Gu, Yen Dang, Gong Lei, Yuming Cao, Xiao Shen, Yu Sheng Bai
  • Patent number: 9921598
    Abstract: A current mirror includes an input transistor and an output transistor, wherein the sources of the input and output transistor are connected to supply voltage node. The gates of the input and output transistor are connected through a switch. A first current source is coupled to the input transistor to provide an input current. A copy transistor has a source connected to the supply node and a gate connected to the gate of the input transistor at a mirror node. A second current source is coupled to the copy transistor to provide a copy current. A source-follower transistor has its source connected to the mirror node and its gate connected to the drain of the copy transistor. Charge sharing at a mirror node occurs in response to actuation of the switch and the source-follower transistor is turned on in response thereto to discharge the mirror node.
    Type: Grant
    Filed: January 3, 2017
    Date of Patent: March 20, 2018
    Assignee: STMicroelectronics S.r.l.
    Inventors: Marco Pasotti, Laura Capecchi, Riccardo Zurla
  • Patent number: 9548308
    Abstract: A nonvolatile memory is provided. A semiconductor device (a nonvolatile memory) has a circuit configuration similar to that of a general SRAM. By providing a transistor whose off-state current is small between a stored data holding portion and a power supply line of the SRAM, leakage of electric charge from the stored data holding portion is prevented. As the transistor whose off-state current is small provided for preventing leakage of electric charge from the stored data holding portion, a transistor including an oxide semiconductor film is preferably used. Such a configuration can also be applied to a shift register, whereby a shift register with low power consumption can be obtained.
    Type: Grant
    Filed: February 16, 2016
    Date of Patent: January 17, 2017
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventor: Yusuke Sekine
  • Patent number: 9311973
    Abstract: An input buffer includes an amplifier circuit configured to amplify an input signal and output an amplified signal to a first output node. The input signal is amplified according to a first bias voltage set, at a bias node, to a first level based on a power supply voltage and a reference voltage. The input buffer includes an output circuit configured to receive and buffer the amplified signal and output an output signal to a second output node. The input buffer includes a dynamic bias voltage generator configured to change the first bias voltage to a second level in response to a transition of the output signal.
    Type: Grant
    Filed: December 2, 2014
    Date of Patent: April 12, 2016
    Assignee: SAMSUNG ELECTRONICS CO., LTD.
    Inventor: Kyoung-tae Kang
  • Patent number: 9299738
    Abstract: The present invention includes an interposer disposed on a surface of a substrate, a light sensing array sensor disposed on the interposer, the light sensing array sensor being back-thinned and configured for back illumination, the light sensing array sensor including columns of pixels, one or more amplification circuitry elements configured to amplify an output of the light sensing array sensor, the amplification circuits being operatively connected to the interposer, one or more analog-to-digital conversion circuitry elements configured to convert an output of the light sensing array sensor to a digital signal, the ADC circuitry elements being operatively connected to the interposer, one or more driver circuitry elements configured to drive a clock or control signal of the array sensor, the interposer configured to electrically couple at least two of the light sensing array sensor, the amplification circuits, the conversion circuits, the driver circuits, or one or more additional circuits.
    Type: Grant
    Filed: June 9, 2014
    Date of Patent: March 29, 2016
    Assignee: KLA-Tencor Corporation
    Inventors: David L. Brown, Guowu Zheng, Yung-Ho Alex Chuang, Venkatraman Iyer
  • Patent number: 9118326
    Abstract: An output circuit has a smaller area and restrains outputs from becoming unstable even if a power supply voltage is lower than an operating voltage. A supply terminal of an inverter circuit is provided with switch circuit, and the switch circuit stops the operation of the inverter circuit when the power supply voltage is lower than the operating voltage of the circuit. Further, the output terminal of the inverter circuit is provided with a current source to fix the output to the power supply voltage when the operation of the inverter circuit is stopped.
    Type: Grant
    Filed: January 23, 2012
    Date of Patent: August 25, 2015
    Assignee: SEIKO INSTRUMENTS INC.
    Inventors: Masahiro Mitani, Naohiro Hiraoka, Masakazu Sugiura, Atsushi Igarashi
  • Patent number: 9071242
    Abstract: A method of making a level shifter includes coupling a driver stage between an input end and an output end, the driver stage comprising a first transistor and a second transistor. An inverter having an input is coupled with the input end. A third transistor having a gate end is coupled with an output of the inverter, the third transistor having a terminal coupled to a pumped voltage (VPP). Additionally, the method includes coupling a fourth transistor with the output end, the fourth transistor having a terminal coupled to the pumped voltage. A fifth transistor is coupled with the input end, the fifth transistor having a terminal coupled to the third and fourth transistors. A sixth transistor is coupled with the input end, the sixth transistor having a terminal.
    Type: Grant
    Filed: December 16, 2013
    Date of Patent: June 30, 2015
    Assignee: TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD.
    Inventors: Tien Chun Yang, Yuwen Swei, Chih-Chang Lin, Chiang Pu
  • Patent number: 7868666
    Abstract: An embodiment of an input-buffer circuit may include an input stage with an inverter having an input operable to receive a signal to be translated. The input stage may include a limiting circuit coupled to the input stage for arresting quiescent current. Additional embodiments of an input-buffer circuit formed according to the subject matter disclosed herein may include feedback transistors suited to provide additional current to the input stage and a hysteresis circuit suited to provide hysteresis current to the input stage when an input signal has a high-frequency change rate.
    Type: Grant
    Filed: April 8, 2009
    Date of Patent: January 11, 2011
    Assignee: Fairchild Semiconductor Corporation
    Inventors: Lei Huang, Weiming Sun
  • Publication number: 20100259298
    Abstract: An embodiment of an input-buffer circuit may include an input stage with an inverter having an input operable to receive a signal to be translated. The input stage may include a limiting circuit coupled to the input stage for arresting quiescent current. Additional embodiments of an input-buffer circuit formed according to the subject matter disclosed herein may include feedback transistors suited to provide additional current to the input stage and a hysteresis circuit suited to provide hysteresis current to the input stage when an input signal has a high-frequency change rate.
    Type: Application
    Filed: April 8, 2009
    Publication date: October 14, 2010
    Inventors: Lei Huang, Weiming Sun
  • Patent number: 7652505
    Abstract: In a level conversion circuit, two P channel MOS transistors form a current mirror circuit. When an input signal rises from the “L” level to the “H” level, an N channel MOS transistor connected to a drain of one P channel MOS transistor is brought out of conduction to prevent a leak current from flowing through two P channel MOS transistors, which decreases a power consumption. In addition, when the input signal rises from the “L” level to the “H” level, a P channel MOS transistor connected to a drain of the other P channel MOS transistor is brought into conduction to fix a potential of a node of the drain of the other P channel MOS transistor to the “H” level, which prevents the potential of the node from becoming unstable.
    Type: Grant
    Filed: August 21, 2008
    Date of Patent: January 26, 2010
    Assignee: Renesas Technology Corp.
    Inventor: Teruaki Kanzaki
  • Patent number: 7598950
    Abstract: A display control device includes a controller, a scaling engine, a timing controller, a selector and an interface circuit. The controller is for providing a mode-control signal. The scaling engine is for producing a first interface signal. The timing controller is for converting the first interface signal into a second interface signal. The selector selects either the first interface signal or the second interface signal to serve as a reference signal according to the mode-control signal. The interface circuit converts the reference signal into an output signal according to the mode-control signal. When the mode-control signal is under a first mode, the output signal is virtually the first interface signal. When the mode-control signal is under a second mode, the output signal is virtually the second interface signal. When the mode-control signal is under a third mode, the interface circuit converts the first interface signal into a third interface signal to serve as the output signal.
    Type: Grant
    Filed: January 31, 2007
    Date of Patent: October 6, 2009
    Assignee: MStar Semiconductor, Inc.
    Inventors: Chih-Tien Chang, Teng-Hann Huang, Chao-Ping Huang
  • Patent number: 7554361
    Abstract: A level shifter and method thereof. The level shifter may include a protective circuit configured to receive an input signal having an input voltage level, the input signal received on an input line, the protective circuit reducing the input voltage level to generate a stabilized input signal and a first inverter configured to invert the stabilized input signal and to output an inverted output signal at an inverted output voltage level to a first node. In an example method, an input signal may be received at an input voltage level, the input voltage level may be reduced to output a stabilized input signal, the stabilized input signal may be inverted to output an inverted output signal at an inverted output voltage level to a first node and the first node may be transitioned to a node voltage level based on the input signal. The level shifter and method thereof may reduce a power consumption and/or a chip size of a semiconductor device.
    Type: Grant
    Filed: July 7, 2005
    Date of Patent: June 30, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Nyun-Tae Kim, Ki-Hong Kim
  • Publication number: 20080129338
    Abstract: Provided is a high-speed asynchronous digital signal level conversion circuit converting an input signal of a first voltage level into a signal of a second voltage level. The conversion circuit is able to operate at high speed by connecting first and second nodes, at which the input signal of the first voltage level is converted to the signal of the second voltage level, to a second power source voltage of the second voltage level for fast voltage level conversion when the voltage level of the input signal is changed.
    Type: Application
    Filed: November 20, 2007
    Publication date: June 5, 2008
    Applicant: Electronics and Telecommunications Research Institute
    Inventors: Min Hyung CHO, Kwi Dong KIM, Chong Ki KWON
  • Patent number: 7336100
    Abstract: A level converter for interfacing two circuits supplied by different supply voltages, and integrated circuit including the level converter interfacing circuit in two different voltage islands. A first buffer is supplied by a virtual supply and receives an input signal from a lower voltage circuit. The first buffer drives a second buffer, which is supplied by a higher supply voltage. An output from the second buffer switches a supply select to selectively pass the higher supply voltage or a reduced supply voltage to the first buffer.
    Type: Grant
    Filed: August 23, 2006
    Date of Patent: February 26, 2008
    Assignee: International Business Machines Corporation
    Inventors: Anthony Correale, Jr., Rajiv V. Joshi, David S. Kung, Zhigang Pan, Ruchir Puri
  • Patent number: 7038491
    Abstract: A programmable level shifter. The programmable level shifter comprises a first P-type FET, a second P-type FET, a third P-type FET, a fourth P-type FET, a fifth P-type FET, a sixth P-type FET, a first N-type FET, a second N-type FET, a third N-type FET, and a programmable device. The first P-type FET is coupled between a first power line and an output node. The first N-type FET is coupled between the first P-type FET and a second power line. The programmable device is coupled between the first power line and the output node, which can be programmed to change an effective resistance between the first power line and the output node when the second P-type FET is turned on.
    Type: Grant
    Filed: July 30, 2004
    Date of Patent: May 2, 2006
    Assignee: Faraday Technology Corp.
    Inventors: Meng-Jer Wey, Chih-Hung Wu
  • Patent number: 6721212
    Abstract: A memory control circuit includes a controller (1A) for controlling a RAM (13) conforming to the standard where source voltage is 2.5 V (SSTL2 standard), and a nonvolatile memory (14) conforming to the standard where source voltage is 3.3 V (LVTTL standard) via a control bus (10) and data buses (11, 12). The control bus (10) for transmitting an address signal and a control signal is shared by these memories (13, 14). The controller (1A) converts internal signals to signals conforming to the standard where source voltage is 2.5 V and outputs the converted signals to the control bus (10). The data buses (11, 12) are provided for the respective memories (13, 14) independently. The number of signal lines can be reduced, and it is possible to prevent signals at high voltage level outputted from the nonvolatile memory (14) from being applied to the RAM (13) driven at low voltages, to cause an occurrence of malfunction at the RAM (13).
    Type: Grant
    Filed: January 2, 2003
    Date of Patent: April 13, 2004
    Assignee: Mega Chips Corporation
    Inventor: Gen Sasaki
  • Patent number: 6456120
    Abstract: A capacitor-coupling differential logic circuit handling the output of a differential circuit using coupling capacitors and sense amplifier. The coupling capacitors can couple a control signal to the corresponding internal terminal, i.e., the output terminal of the differential circuit. During evaluation, the differential circuit generates a voltage difference on the internal signal of the internal terminal according to the input signal and the predetermined logic operation. The sense amplifier is used to amplify and output the voltage difference on the internal; signal at the internal terminal.
    Type: Grant
    Filed: November 8, 2000
    Date of Patent: September 24, 2002
    Assignee: Industrial Technology Research Institute
    Inventor: Hong-Yi Huang
  • Patent number: 6411140
    Abstract: The integrated circuit includes an input path circuit with an address path having an input buffer for providing address signals to a register. A separate clock path having an input buffer provides a clock signal for clocking the register. The input buffers of both the address path and the clock path include input buffer cells configured to reduce timing delay differences caused by process variations while minimizing current leakage. An exemplary input buffer cell described herein includes a first inverter stage with a pair of NMOS devices connected in series with a PMOS device and a second inverter stage having an additional PMOS device connected along a feedback path around an inverter. The PMOS device along the feedback path operates to assist the pair of NMOS devices to pull a voltage input to the inverter to a high logic state, when an input to the cell is held low, to prevent leakage current through the inverter.
    Type: Grant
    Filed: May 7, 1999
    Date of Patent: June 25, 2002
    Assignee: Cypress Semiconductor Corporation
    Inventor: Greg J. Landry
  • Publication number: 20020003437
    Abstract: The circuit configuration for converting logic levels has a bipolar input stage and a CMOS output stage. The bipolar input stage is equipped to process ECL and CML logic levels. The CMOS-logic output stage is equipped to supply trailing CMOS gates having CMOS logic levels. A difference amplifier includes bipolar transistors, which are connected to a common emitter current source and to separate collector current sources. An input-output feedback CMOS inverter is connected to one of the collectors, and the output of the inverter is coupled to an output node.
    Type: Application
    Filed: June 14, 2001
    Publication date: January 10, 2002
    Inventor: Timo Gossmann
  • Patent number: 6307396
    Abstract: A low-consumption TTL-CMOS input buffer stage includes a chain of inverters cascade connected between an input receiving electric signals at a TTL logic level and an output reproducing electric signals at a CMOS logic level, and powered between a first or supply voltage reference and a second or ground reference. Advantageously, the first inverter in the chain includes a means of selecting the delivery path to the stage according to an activate signal for a low-consumption operation mode. In essence, the first inverter of the buffer has two signal paths: one for normal operation and the other for low consumption operation.
    Type: Grant
    Filed: December 30, 1998
    Date of Patent: October 23, 2001
    Assignee: STMicroelectronic S.r.l.
    Inventors: Jacopo Mulatti, Marco Maccarrone, Ignazio Martines, Rino Micheloni
  • Patent number: 6236236
    Abstract: An apparatus and method of communicating signals between a 2.5 volt internal circuit and both 3.3 and 5 volt external circuits using a P-well. The apparatus includes a circuit having a P-well control circuit and a number of NMOS transistors. The P-well control circuit is configured to receive a P-well control signal and an external signal, and in accordance therewith selectively generate a P-well voltage. The NMOS transistors are coupled to the P-well control circuit. At least one of the NMOS transistors has a bulk region configured to receive the P-well voltage. The NMOS transistors are further configured to receive a 5 volt signal and in accordance therewith selectively generate a 2.5 volt signal. The NMOS transistors are still further configured to receive a 3.3 volt signal and in accordance therewith selectively generate a 2.5 volt signal.
    Type: Grant
    Filed: June 2, 1999
    Date of Patent: May 22, 2001
    Assignee: National Semiconductor Corporation
    Inventor: Deng-Yuan David Chen
  • Patent number: 6232803
    Abstract: A driver circuit is provided comprising a detection circuit, configured to sense a plurality of different variable operating condition signals, and in accordance therewith, provide a plurality of operating condition dependent output signals; a selection circuit, having a plurality of output signals, configured to receive said plurality of operating condition dependent output signals, and in accordance therewith, discretely enable, during a non-transmission state, an N number of enabled output signals; and an output circuit, having a plurality of identical segmented output modules, each of the output modules associated with a respective one of the plurality of output signals and configured to provide a respective output driving signal, wherein the output modules associated with the N number of enabled output signals each provide the output driving signal.
    Type: Grant
    Filed: May 13, 1999
    Date of Patent: May 15, 2001
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Thai M. Nguyen
  • Patent number: 6097216
    Abstract: Integrated buffer circuits which are less susceptible to noise and provide TTL-to-CMOS signal conversion capability include a first TTL-compatible inversion buffer, a second CMOS-compatible inversion buffer having an input electrically coupled to an output of the first inversion buffer and a preferred pull-up (or pull-down) circuit to improve noise immunity. The preferred circuit pulls the output of the first inversion buffer to a potential of the first reference signal line (e.g., Vdd) in response to a signal at an output of the second inversion buffer and a signal at an input of the first inversion buffer. This circuit comprises a first field effect transistor having a gate electrode electrically coupled to the output of the second inversion buffer and a second field effect transistor having a gate electrode electrically coupled to the input of the first inversion buffer.
    Type: Grant
    Filed: September 8, 1998
    Date of Patent: August 1, 2000
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Jae-youn Youn
  • Patent number: 6091264
    Abstract: A circuit and a method are disclosed for a Schmitt trigger stage which converts transistor-transistor logic (TTL) into metal oxide semiconductor (MOS) logic signal levels using all MOS devices. The circuit reduces the standby current of the n-channel transistor of the input section of the Schmitt trigger stage by adding a MOS diode to the bottom the input section. When higher than normal supply voltages are used, the standby current of the p-channel transistor of the input section can be reduced by adding a MOS diode to the top of the input section. In addition, a small MOS transistor, connected across the output Schmitt trigger inverter, eliminates leakage currents in that inverter.
    Type: Grant
    Filed: May 27, 1998
    Date of Patent: July 18, 2000
    Assignee: Vanguard International Semiconductor Corporation
    Inventors: Howard C. Kirsch, Yen-Tai Lin, Yu-Ming Hsu
  • Patent number: 6069492
    Abstract: A voltage compensating CMOS input buffer converts input TTL signals to CMOS logic levels, and compensates for changing supply voltage by using a n-channel transistor to vary the effective size ratio of pairs p-channel to n-channel transistors making up an input inverter. The compensating transistor becomes operable with increasing supply voltage to help the n-channel input inverter transistors offset the p-channel input inverter transistors whose trip points would otherwise have been increased by increasing power supply voltage. As the power supply voltage decreases, the compensating transistor turns off, returning the input inverter to its original size ratio. The gate of the compensating transistor is coupled to the supply voltage through two diodes to control the amount of current flowing through the compensating transistor. Further trip point transistors in series with the compensating transistor have their gates coupled to the input signals to help stabilize the trip points.
    Type: Grant
    Filed: September 8, 1997
    Date of Patent: May 30, 2000
    Assignee: Micron Technology, Inc.
    Inventors: Joseph C. Sher, Manny K. F. Ma
  • Patent number: 6064226
    Abstract: The present invention provides an input receiver in a differential amplifier or modified differential amplifier configuration which adjusts the input high and low voltage signals compatible with multiple input/output (I/O) interfaces, including transistor-transistor logic (TTL), Low Voltage TTL (LVTTL), and Stub Series Terminated Logic (SSTL) interfaces. Transistors in a differential amplifier or modified differential amplifier configuration that receive a reference.sub.-- voltage signal and receiver.sub.-- enable signal are adjusted in accordance to the input high signal and input low signal requirements for a selected type of interface, while other transistors remain at a relatively constant voltage. Once a particular type of interface has been selected, the gate voltages for the transistors that receive the reference.sub.-- voltage and receiver.sub.-- enable signals remain relatively constant.
    Type: Grant
    Filed: March 17, 1998
    Date of Patent: May 16, 2000
    Assignee: Vanguard International Semiconductor Corporation
    Inventor: Jeffrey S. Earl
  • Patent number: 6040714
    Abstract: The present invention provides a method of providing two different modes of operation for an output driver on an integrated circuit. A first mode provides an open drain driver, such as an enhanced GTL+ driver, for high-speed data transmission. A second mode provides a totem pole output driver, such as a TTL or a LVTLL driver, which does not require additional circuitry for external terminations, as is required for open drain drivers. Thus, one embodiment of the present invention can be characterized as a method of providing a dual mode output from an integrated circuit. This method includes receiving an output mode signal indicating an enhanced GTL+ output mode or a totem pole output mode. This method also includes providing an enhanced GTL+ output signal if the mode signal indicates the enhanced GTL+ output mode, and providing a totem pole output signal if the mode signal indicates the totem pole output mode.
    Type: Grant
    Filed: December 12, 1997
    Date of Patent: March 21, 2000
    Assignee: Micron Electronics, Inc.
    Inventor: Dean A. Klein
  • Patent number: 5986472
    Abstract: Circuit and method aspects are provided for voltage level translation circuit for an output driver. In a circuit aspect, a circuit includes an input mechanism for receiving an internal data signal of a first predetermined voltage range, at least two stacked transistors coupled to the input mechanism, and a bias generator coupled to the input mechanism and the at least two stacked transistors, the bias generator ensuring that the at least two stacked transistors operate below a predetermined maximum device voltage. The circuit further includes an output mechanism coupled to the at least two stacked transistors, the output mechanism providing an external signal of a second predetermined voltage range.
    Type: Grant
    Filed: June 6, 1997
    Date of Patent: November 16, 1999
    Assignee: International Business Machines Corporation
    Inventors: Fahd Hinedi, Moises Cases, Satyajit Dutta, Robert Heath Dennard
  • Patent number: 5955893
    Abstract: An embodiment of the invention provides a buffer circuit having reduced power consumption. The buffer circuit comprises a power saving switch coupled to a buffer at a bias node. The buffer has an input that is adapted to receive input voltages at TTL levels, for example, and has an output adapted to provide output voltages at CMOS levels, for example. The power saving switch includes a level shifter and a voltage control circuit both coupled to the bias node. The output voltage of the buffer is fed back to the power saving switch. When the output voltage is at a low CMOS level, the power saving switch uses the voltage control circuit to provide a first bias voltage to the bias node. When the output voltage is at a high CMOS level, the power saving switch uses the level shifter to provide a second bias voltage to the bias node. The second bias voltage is chosen such that it prevents current flow between the bias node and the buffer at a predetermined input cutoff voltage.
    Type: Grant
    Filed: December 16, 1996
    Date of Patent: September 21, 1999
    Assignee: Macronix International Co., Ltd.
    Inventors: Kuen-Long Chang, Chun-Hsiung Hung, Yin-Shang Liu
  • Patent number: 5945844
    Abstract: A buffer circuit (10). The buffer circuit (10) includes a first inverter (12) with a first current limiter (18) that limits the standby current used by the first inverter (12). Further, the buffer circuit (10) includes a second inverter (14) that is coupled to an output of the first inverter (12). The input buffer (10) converts a first logic level of an input signal provided to the first inverter (12) to a second logic level at an output of the second inverter (14). The buffer circuit (10) also includes a second current limiting circuit (16) that is coupled between the first and second inverters (12 and 14) to further limit the standby current in the buffer circuit (10).
    Type: Grant
    Filed: August 20, 1998
    Date of Patent: August 31, 1999
    Assignee: Micron Technology, Inc.
    Inventor: Huy Thanh Vo
  • Patent number: 5905386
    Abstract: A pulse receiver, comprising a pair of complementary symmetry metal oxide silicon (CMOS) common gate amplifiers connected between a 5 volt supply (ECL) voltage rail and an ECL ground (AGND), for receiving a pair of pulse input signals IN and INB and for providing a pair of first pulse signals, CMOS apparatus for distorting the first pulse signals, to create second pulse signals from the converter having a duty cycle having a longer low logic level interval than high logic level interval, a CMOS latch for receiving and latching the second output signals from the common gate amplifiers at logic levels compatible with circuits formed of CMOS elements, a CMOS double to single ended converter connected between a VDD voltage rail and VSS ground, for receiving the latched output signals, apparatus for providing an output signal referenced to VDD and ground from the converter.
    Type: Grant
    Filed: February 27, 1998
    Date of Patent: May 18, 1999
    Assignee: PMC-Sierra Ltd.
    Inventor: Brian Donald Gerson
  • Patent number: 5883528
    Abstract: An input circuit to a semiconductor device may selectively accept different voltage logic levels (e.g., TTL or CMOS) as selected by a preset selection signal. The selection signal activates an N-type or P-type transistor in the input circuit which alters the threshold switching voltage of the input circuit logic. By altering the input threshold voltage, both TTL and CMOS input signals may be correctly triggered. An additional circuitry may be provided to allow a low voltage circuit (e.g., 3.3 Volts) to be tolerant of higher voltage inputs (e.g., 5 Volts). An isolation transistor isolates the input of the circuit from the high voltage signal, while a pulldown transistor pulls a high logic, high voltage signal down to supply voltage level.
    Type: Grant
    Filed: March 20, 1997
    Date of Patent: March 16, 1999
    Assignee: Cirrus Logic, Inc.
    Inventors: Abdul Qayyum Kashmiri, Junaid Ahmed Ahmed, Han My Kim
  • Patent number: 5880601
    Abstract: A signal receiving circuit comprising a first P-channel MOSFET amplifier and a first N-channel MOSFET amplifier having gates supplied with positive signals from a pair of signal transmission lines; and a second P-channel MOSFET amplifier and a second N-channel MOSFET amplifier having gates supplied with negative signals from said pair of signal transmission lines; wherein a first output signal is formed by so adjusting the gains of the first P-channel MOSFET amplifier and of the second N-channel MOSFET amplifier that the resultant signals have an intermediate amplitude between the operation voltages, and a second output signal is formed by so adjusting the gains of the second P-channel MOSFET amplifier and of the first N-channel MOSFET amplifier that the resultant signals have an intermediate amplitude between the operation voltages.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: March 9, 1999
    Assignees: Hitachi, Ltd., Hitachi Communication Systems, Inc.
    Inventors: Nobuaki Kanazawa, Masao Mizukami, Kunihiro Ito
  • Patent number: 5872464
    Abstract: The present invention provides a circuit and method using a floating PMOS transistor connected in series between the transistors of an input invertor. The floating PMOS transistor may be used to control the amount of current through the transistors. The gate of the floating PMOS transistor may be connected through a reference line to a duplicate of the input inverter stage. The duplicate stage is generally located in a reference block and fed with a stabilized reference voltage. Each couple (formed by the buffers input stage and the duplicate stage) functions as a differential comparator, which checks the input voltage against the reference voltage and rejects the power supply voltage variations which are perceived as a common-mode noise signal. The supply current is fixed by the reference voltage which reduces power consumption at high input voltages and high supply voltages.
    Type: Grant
    Filed: August 12, 1996
    Date of Patent: February 16, 1999
    Assignee: Cypress Semiconductor Corp.
    Inventor: Julian C. Gradinariu
  • Patent number: 5861763
    Abstract: A buffer circuit (10). The buffer circuit (10) includes a first inverter (12) with a first current limiter (18) that limits the standby current used by the first inverter (12). Further, the buffer circuit (10) includes a second inverter (14) that is coupled to an output of the first inverter (12). The input buffer (10) converts a first logic level of an input signal provided to the first inverter (12) to a second logic level at an output of the second inverter (14). The buffer circuit (10) also includes a second current limiting circuit (16) that is coupled between the first and second inverters (12 and 14) to further limit the standby current in the buffer circuit (10).
    Type: Grant
    Filed: August 22, 1997
    Date of Patent: January 19, 1999
    Assignee: Micron Technology, Inc.
    Inventor: Huy Thanh Vo
  • Patent number: 5751166
    Abstract: A method and a circuit for automatically adjusting a switching threshold of an input buffer circuit (100) to conform to an input signal V.sub.IN which can be from either a TTL or a CMOS logic family. A latch circuit (120) is initialized to set the switching threshold to that of one of the logic families. A level shifting circuit (130) has a switchable load which varies the switching threshold under the control of the latch circuit (120). The amplitude of the input signal V.sub.IN is detected in a threshold detector circuit (110). If the input signal V.sub.IN is a signal from the CMOS logic family, the latch circuit (120) changes state, switching the switchable load of the level shifting circuit (130) to adjust the switching threshold of the input buffer circuit (100).
    Type: Grant
    Filed: June 4, 1996
    Date of Patent: May 12, 1998
    Assignee: Motorola, Inc.
    Inventors: Jhy-Jer Shieh, Dandas K. Tang
  • Patent number: 5731713
    Abstract: A CMOS input buffer is described for such CMOS circuits as dynamic random access memories, microprocessors, and the like, for receiving TTL logic high and low level signals. The input buffer includes an input stage formed from a p-channel and n-channel MOS transistors configured to have substantially equal transconductances, connected to form a series current path between a bias voltage and a lower voltage (e.g., ground), setting the trip point of the input stage approximately midway between the typically specified TTL logic high and low levels. The differential between the bias and lower voltages from which the input buffer operates assures that at least one of the MOS transistors is off for a TTL logic high or low level input, obviating power consumption while the input signal is at such level. The input buffer is also made insensitive to symmetrical power supply noise, consumes less power, and is made insensitive to threshold voltage variations.
    Type: Grant
    Filed: August 27, 1996
    Date of Patent: March 24, 1998
    Assignee: Townsend and Townsend and Crew LLP
    Inventors: Robert J. Proebsting, Hyunsoo Sim
  • Patent number: 5703500
    Abstract: A buffer circuit (10). The buffer circuit (10) includes a first inverter (12) with a first current limiter (18) that limits the standby current used by the first inverter (12). Further, the buffer circuit (10) includes a second inverter (14) that is coupled to an output of the first inverter (12). The input buffer (10) converts a first logic level of an input signal provided to the first inverter (12) to a second logic level at an output of the second inverter (14). The buffer circuit (10) also includes a second current limiting circuit (16) that is coupled between the first and second inverters (12 and 14) to further limit the standby current in the buffer circuit (10).
    Type: Grant
    Filed: May 15, 1996
    Date of Patent: December 30, 1997
    Assignee: Micron Technology, Inc.
    Inventor: Huy Thanh Vo
  • Patent number: 5654664
    Abstract: An input buffer circuit of a semiconductor memory capable of controlling a logic threshold voltage of the circuit according to a change in an external supply voltage, which includes an external supply voltage detecting unit for dividing the external supply voltage into a plurality of regions by comparing a plurality of voltages, which have been divided by different ratios of the entire external supply voltage, with a standard voltage; and a converting unit including a pull-up circuit and a pull-down circuit, for converting input signals of TTL level into signals of CMOS level, according to the regions of the external supply voltage obtained by the external supply voltage detecting unit.
    Type: Grant
    Filed: March 28, 1996
    Date of Patent: August 5, 1997
    Assignee: LG Semicon Co., Ltd.
    Inventors: Jong-Hoon Park, Jae-Woon Kim
  • Patent number: 5633602
    Abstract: A means of converting low voltage CMOS logic levels operating with a 3.3 volts logic level to low voltage PECL logic levels operating with a 3.3 volts supply voltage and a 0.8 volts logic level. The circuit design is process insensitive, and the characteristics of the converter emulate the emitter follower outputs of ECL devices. The converter solves the signal ringing problems caused by open output conditions, and is less susceptible to electromagnetic interference.
    Type: Grant
    Filed: September 14, 1995
    Date of Patent: May 27, 1997
    Assignee: NCR Corporation
    Inventors: Ikuo J. Sanwo, Joseph D. Russell, Juei-Po Lin
  • Patent number: 5612635
    Abstract: A buffer circuit for converting logic signals generated by apparatus implemented in a TTL technology to logic signals processed by apparatus implemented by the CMOS technology includes an input stage (10, 11, 12, 13, 17), a voltage-control (14, 15) stage for causing the buffer circuit to vary the input voltage level required to switch the state of the buffer circuit output signal, and a hysteresis stage (16) for causing the switching of the output signal level to be different for the rising and falling edges of the input signal. The voltage-control stage (14, 15) provides a improvement in the noise margin of both the VTTL(High) switching level and the VTTL(Low) switching level.
    Type: Grant
    Filed: March 22, 1995
    Date of Patent: March 18, 1997
    Assignee: Texas Instruments Incorporated
    Inventors: Raghava Madhu, Subramani Kengeri
  • Patent number: 5602496
    Abstract: An input buffer circuit is disclosed which provides better noise margin and sharper switching edges than previously known systems. This circuit includes an input level translator, a Schmitt trigger circuit coupled to the input level translator circuit, a buffer, and sleep function circuit. The sleep function circuit reduces power when the input buffer circuit is powered down. The Schmitt trigger circuit comprises the hysteresis transfer characteristic providing means of the present invention. The Schmitt trigger circuit and buffer circuit, both with properly matched beta values for the participating transistors, allows for improved noise immunity of and sharper switching edges for the input buffer of the present invention.
    Type: Grant
    Filed: May 23, 1996
    Date of Patent: February 11, 1997
    Assignee: Advanced Micro Devices, Inc.
    Inventor: Qazi Mahmood
  • Patent number: 5602495
    Abstract: An inverter receives an energizing voltage with a particular magnitude (e.g. 1.5 V) at a first terminal and produces the voltage at a second terminal. The received and produced voltages are differentially introduced to a stage which produces a single-ended bias voltage (e.g. 3 V) related to the second terminal voltage. The bias voltage is servoed to regulate the second terminal voltage (e.g. 1.5 V) and the bias voltage (e.g. 3 V) regardless of energizing voltage variations. In response to the bias voltage and a variable input voltage, a pass transistor in a buffer produces a first control voltage different from the bias voltage by the pass transistor threshold voltage for input voltages greater than the bias voltage less the pass transistor threshold. The first control voltage corresponds to the input voltage for input voltages less than the bias voltage less the pass transistor threshold.
    Type: Grant
    Filed: May 4, 1995
    Date of Patent: February 11, 1997
    Assignee: Brooktree Corporation
    Inventor: Perry W. Lou
  • Patent number: 5600267
    Abstract: A CMOS circuit is disclosed for translating a signal from CML to CMOS logic voltage levels. The CMOS circuit includes two amplifier circuits coupled in parallel. The first amplifier circuit comprises of a programmable circuit and a CMOS inverter such that the CMOS inverter can be programmed "on" or "off" by the programmable circuit. The programmable circuit includes a programmable element which may be implemented using a fuse or floating gate technology. The second amplifying circuit comprises of a CMOS inverter. When the CMOS inverter in the first amplifier circuit is powered "on", the CMOS circuit is operating in a full power mode at high speed with both CMOS inverters operating. When the CMOS inverter in the first amplifier circuit is powered "off", the CMOS circuit is operating in a low power mode at a slower speed with only one CMOS inverter operating.
    Type: Grant
    Filed: November 28, 1995
    Date of Patent: February 4, 1997
    Assignee: Cypress Semiconductor Corporation
    Inventors: Sing Y. Wong, Donald Yu, Roger Bettman
  • Patent number: 5589783
    Abstract: According to the present invention, an integrated circuit device is capable of responding to more than one input threshold voltage level by making only minimal changes to the device. The input buffer of the integrated circuit device is modified to be a programmable buffer that is controlled by a control input signal which may be generated by several different control means. Such control means include a bond option, a mask option, a fuse option, a register option, and a voltage detector option.
    Type: Grant
    Filed: July 29, 1994
    Date of Patent: December 31, 1996
    Assignee: SGS-Thomson Microelectronics, Inc.
    Inventor: David C. McClure
  • Patent number: 5559461
    Abstract: A drive circuit includes first and second circuit sections. The first circuit section maintains, during an initial stage of a transient period of an input signal, its output level before the signal transition and supplies after the transient period an output signal responsive to the signal transition. The second circuit section has a first circuit portion receiving the input signal and a second circuit portion, responsive to the input signal, and the output of the first circuit section, to accelerate the signal transition of the first circuit portion. Signal delay in a signal transition due to a large parasitic capacitance and resistance can be recovered by the drive circuit. The drive circuit has a large noise margin and operates at a high-speed and in a wide frequency range.
    Type: Grant
    Filed: June 27, 1995
    Date of Patent: September 24, 1996
    Assignee: NEC Corporation
    Inventors: Masakazu Yamashina, Youichi Koseki, Masayuki Mizuno
  • Patent number: 5557219
    Abstract: A system of interface circuits (15, 20-1 through 20-N) includes a mode sensing circuit (15) and one or more output circuits (20-1 through 20-N). The mode sensing circuit is arranged for producing control signals (on leads 22, 24) in response to an input signal (on lead 21). The output circuit (34-1) is arranged for producing an output data signal (DQ-1) dependent upon an input data signal (DATA) when the input signal (on lead 21) is in a first state and dependent upon the input data signal and the configuration of the connected output circuit (34-1) when the input signal is in a second state.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: September 17, 1996
    Assignee: Texas Instruments Incorporated
    Inventors: Roger D. Norwood, Brian L. Brown