Temperature Compensation Of Semiconductor Patents (Class 323/907)
  • Patent number: 5675243
    Abstract: A voltage source device for low-voltage operation which sources a desired voltage while minimizing variations in output voltage due to changes in temperature. The voltage source device includes a current source circuit having a temperature characteristic of (1/T)-a and a compensation circuit having a temperature characteristic that includes a term of -1/T, which compensates for the temperature characteristic of the current source circuit. The voltage source device also includes a voltage conversion circuit for converting the power supply current provided by the current source circuit into a power supply voltage and outputting it externally.
    Type: Grant
    Filed: April 10, 1996
    Date of Patent: October 7, 1997
    Assignee: Motorola, Inc.
    Inventor: Takatsugu Kamata
  • Patent number: 5666046
    Abstract: A method for generating a programmable bandgap output reference voltage (V.sub.REF31) and a voltage reference circuit (31) have been provided. The voltage reference circuit (31) includes a pair of bipolar transistors (33, 34), a resistor (36), an operational amplifier (32) and a plurality of field effect transistors (38, 39, 41) configured to generate a current (I.sub.1 ') having a positive temperature coefficient. In addition, the voltage reference circuit (31) includes a resistor (46), an operational amplifier (44), another plurality of field effect transistors (47, 48) which, in conjunction with one (34) of the pair of bipolar transistors, generates a current (I.sub.2 ') having a negative temperature coefficient. The current (I.sub.1 ') having the positive temperature coefficient is summed with the current (I.sub.2 ') having the negative temperature coefficient to form a current having a zero temperature coefficient, which is used to develop a voltage having a zero temperature coefficient.
    Type: Grant
    Filed: August 24, 1995
    Date of Patent: September 9, 1997
    Assignee: Motorola, Inc.
    Inventor: David F. Mietus
  • Patent number: 5646518
    Abstract: Briefly, in accordance with one embodiment of the invention, a current source comprises: a first and a second current path, the current paths being coupled so as to provide, during circuit operation, first and second currents through the respective current paths in a substantially predetermined direct proportion. The current source further includes an operational amplifier having its respective input terminals coupled to the first and second current paths, the operational amplifier being coupled in a feedback configuration so as to maintain substantially equal voltages between a first and second predetermined point respectively located along the first and second current paths. Furthermore, the respective first and second currents are related to the respective first and second voltages substantially in accordance with the junction diode equation.
    Type: Grant
    Filed: November 18, 1994
    Date of Patent: July 8, 1997
    Assignee: Lucent Technologies Inc.
    Inventors: Kadaba R. Lakshmikumar, Krishnaswamy Nagaraj, David Arthur Rich, Khong-Meng Tham
  • Patent number: 5646517
    Abstract: A voltage regulator controls at least one current source of at least one coupled-mode logic gate. The voltage regulator includes a first current source, of a bipolar-type, connected between ground and a first resistor that is connected to a supply voltage. The first current source is controlled by a voltage across a second resistor that is fed by a current from a second current source of a MOS-type. The current value of the second source determines the voltage of an output terminal of the regulator by duplicating this current on a third current source that is mirror-connected to the second source.
    Type: Grant
    Filed: November 22, 1995
    Date of Patent: July 8, 1997
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventors: Didier Belot, Patrick Bernard
  • Patent number: 5644216
    Abstract: In order to give the current the quality of low sensitivity to temperature, a first MOS transistor and a second MOS transistor supplied by a current mirror have their sources connected to the ground, with the drain and the gate of the first transistor being connected to the gate of the second transistor by means of a resistor. The quotient of the dimensional ratios of the transistors is equal to the coefficient of the current mirror and the transistors are doped so that the threshold of the second transistor is greater than that of the first one. Application notably to ramp generators for the programming of EEPROM cells.
    Type: Grant
    Filed: May 31, 1995
    Date of Patent: July 1, 1997
    Assignee: SGS-Thomson Microelectronics, S.A.
    Inventors: Joaquin Lopez, Jean-Michel Coquin
  • Patent number: 5629612
    Abstract: Methods and apparatus for improving the temperature drift of references by providing temperature compensation trimmable after packaging of the integrated circuit. In accordance with the method, first, second and third trim parameters are generated and trimmed at wafer sort so that the first parameter is substantially independent of temperature, and at a nominal temperature, the second and third parameters are zero, with the second being proportional to the temperature rise above nominal and the third being proportional to temperature decrease below nominal.
    Type: Grant
    Filed: March 12, 1996
    Date of Patent: May 13, 1997
    Assignee: Maxim Integrated Products, Inc.
    Inventor: Gregory L. Schaffer
  • Patent number: 5627456
    Abstract: An integrated current reference circuit provides a current output with a predetermined temperature coefficient, suitably zero, to provide constant current over temperature variations. The circuit is formed of only Field Effect Transistors (FETs), allowing the circuit to be implemented using conventional CMOS fabrication techniques. A current mirror provides a reference current in both branches of the circuit. The output of the current mirror is coupled to a circuit providing an imbalance in resistance between the two branches, and an offsetting imbalance in voltages between the two branches, resulting in a reference current that has a predetermined temperature coefficient. An output current is provided which is proportional to the reference current and thus has the same temperature coefficient as the reference current.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: May 6, 1997
    Assignee: International Business Machines Corporation
    Inventors: Ilya I. Novof, John E. Gersbach, Frank D. Ferraiolo
  • Patent number: 5621307
    Abstract: A precision voltage reference temperature compensated circuit 10 uses forward biased Zener diodes D2, D4 to provide a negative temperature coefficient compensation circuit and reverse biased Zener diodes D5-D6 to provide a positive temperature coefficient compensation circuit. Use of only Zener diodes results in a circuit 10 with fast recovery to the expected output voltage from transient events such as power supply perturbations, output load switching and/or gamma radiation events. The reference output voltage V.sub.out temperature characteristic is finally established by trimming resistors R3, R4 that are coupled between the current source including transistor Q1 and a positive temperature coefficient compensation circuit of diodes D5-D7. The precision reference output voltage level is finally established by trimming the resistors R5 and R6 that are coupled between the output of the temperature coefficient trim network and ground.
    Type: Grant
    Filed: July 21, 1995
    Date of Patent: April 15, 1997
    Assignee: Harris Corporation
    Inventor: Kristin M. Beggs
  • Patent number: 5621306
    Abstract: The invention provides a voltage-generating circuit in which the characteristic of the output voltage in response to the ambient temperature is represented by a predetermined line. A temperature sensor outputs a voltage in proportion to the ambient temperature, and the voltage is inversely amplified by an operational amplifier. An optimum operating voltage V.sub.op for a liquid crystal is output from an output terminal of a variable voltage regulator, in response to the voltage output ted from the operational amplifier.
    Type: Grant
    Filed: October 18, 1994
    Date of Patent: April 15, 1997
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Masahiro Ise
  • Patent number: 5619122
    Abstract: In accordance with the teachings of the present invention, a temperature dependent voltage generator circuit is provided for generating an output voltage that changes proportionally with changes in the operating temperature of the temperature dependent voltage generator circuit. The temperature dependent voltage generator circuit includes binary weighted current sources and electronic switches that are selectively closed in order to produce a binary weighted current. The binary weighted current is adjustable such that the output voltage of the temperature dependent voltage generator circuit may be "nulled" or forced to zero at any given operating temperature.
    Type: Grant
    Filed: April 14, 1995
    Date of Patent: April 8, 1997
    Assignee: Delco Electronics Corporation
    Inventors: Mark B. Kearney, Dennis M. Koglin
  • Patent number: 5614816
    Abstract: A voltage reference generator circuit (600) that operates at low voltages may be obtained by using a summation circuit (618) to combine a divided bipolar junction voltage signal (616) and a multiplied voltage signal (622) that is proportional to absolute temperature. The voltage reference generator circuit (600) generates a voltage reference which is divided by a divide circuit (620) which produces the divided signal (616), and a voltage reference which is multiplied by a multiply circuit (630) which produces the multiplied signal (622). In another form, a bipolar junction voltage and a voltage that is proportional to absolute temperature may be converted to currents and summed to provide a current which is converted into the reference voltage output.
    Type: Grant
    Filed: November 20, 1995
    Date of Patent: March 25, 1997
    Assignee: Motorola Inc.
    Inventor: Joseph J. Nahas
  • Patent number: 5604466
    Abstract: An on-chip voltage controlled oscillator for use in an analog phase locked loop receives power from a voltage regulator which greatly reduces the noise seen by the voltage controlled oscillator. The voltage controlled oscillator has a DC bias section which supplies a relatively constant current to the multivibrator to assure a minimum operating frequency. A control signal is used to provide additional current which increases the speed of oscillation. The bias current reduces the transfer characteristics (MHz/volt) of the voltage controlled oscillator making it more immune to noise in the control signal.
    Type: Grant
    Filed: November 28, 1994
    Date of Patent: February 18, 1997
    Assignee: International Business Machines Corporation
    Inventors: Daniel M. Dreps, Raymond P. Rizzo
  • Patent number: 5604467
    Abstract: A temperature compensated current source for driving a multi-vibrator (19) includes a voltage generator (10) that outputs a voltage that is proportional to absolute temperature (PTAT) and a resistor (12) for setting the current output by the voltage generator (10). The temperature coefficient of the resistor (12) is chosen such that any variations in the current supplied by the voltage generator (10) are compensated for to result in a current that has substantially no temperature variation. This current is mirrored to a current source (18) for driving the multi-vibrator (19). The voltage across the resistor (12)is a function of temperature, with the current being a function of the value of the resistor (12). The temperature coefficient of the resistor (12) is substantially equal to the temperature coefficient of the voltage generator (10) to yield a temperature coefficient of substantially 0 ppm/.degree.C. for the current.
    Type: Grant
    Filed: February 11, 1993
    Date of Patent: February 18, 1997
    Assignee: Benchmarg Microelectronics
    Inventor: Wallace E. Matthews
  • Patent number: 5604427
    Abstract: A current reference circuit producing a reference current without temperature dependence and operating at a low supply voltage, which includes a first current source for producing a first constant current having a positive temperature coefficient, a second current source for producing a second constant current having a negative temperature coefficient, and an adder for adding the first and second constant currents to cancel their positive and negative temperature coefficients. The second current source contains first and second bipolar transistors and a resistor connected between a base and an emitter of the first bipolar transistor, and a bias subcircuit for supplying the reference current to the first bipolar transistor. The emitter of the first bipolar transistor is connected to an emitter of the second bipolar transistor, and a collector of the first bipolar transistor is connected to a base of the second bipolar transistor.
    Type: Grant
    Filed: October 24, 1995
    Date of Patent: February 18, 1997
    Assignee: NEC Corporation
    Inventor: Katsuji Kimura
  • Patent number: 5602466
    Abstract: A dual output temperature compensated voltage reference includes a voltage reference circuit (201) having a first output (203) for providing a first signal (204) dependent on temperature, and a second output (207) for providing a second signal (208) dependent on the first signal (204). A temperature dependence of the first signal (204) has a slope opposite a temperature dependence of the second signal (208). A cooperative device (209), such as a resistive divider (309, 311), combines the first and second signals (204, 208) and provides a third signal (212) dependent on the first and second signals (204, 208). Preferably, this apparatus is applied in a charge regulator including fault detection (109). The charge regulator (109) generates a charge voltage (110) dependent on the first signal (204) and a fault detection function is dependent on the third signal (212).
    Type: Grant
    Filed: February 22, 1994
    Date of Patent: February 11, 1997
    Assignee: Motorola Inc.
    Inventor: Arthur J. Edwards
  • Patent number: 5596265
    Abstract: The preferred embodiment voltage regulator exhibits improved stability by offsetting changes in the output impedance of the regulator due to changes in load current. This compensation occurs virtually instantaneously with a change in load current. This enables an output capacitor to be selected primarily based upon filtering requirements rather than on frequency compensation requirements. Also in the preferred embodiment, a depletion mode pass transistor is used as the output transistor. A PMOS transistor on/off switch is connected between the source of the pass transistor and the output terminal of the regulator to effectively turn the regulator on or off without shutting down the depletion mode pass transistor. This avoids the need to form a negative supply voltage generator. An improved band gap voltage reference generator is also described which introduces a beta correction factor into the output voltage which offsets changes in beta due to process variations and other conditions.
    Type: Grant
    Filed: February 14, 1995
    Date of Patent: January 21, 1997
    Assignee: Siliconix incorporated
    Inventors: Robert S. Wrathall, Steven J. Franck
  • Patent number: 5587655
    Abstract: A constant current circuit of the invention supplies a constant current to a load. The constant current circuit is formed of a current source device for providing an input current having a predetermined value with temperature dependence, a voltage divider device connected to the current source device, and an output transistor device. A reference transistor device or an adjusting transistor device is attached to the current source device. In case the reference transistor device is used, the voltage divider device divides a reference voltage of the reference transistor device to thereby generate a control voltage. In case the adjusting transistor device is used, an adjusting voltage from the voltage divider device is supplied to the adjusting transistor device to generate a control voltage. The output transistor device is connected to the load for controlling an output current supplied to the load in response to the control voltage.
    Type: Grant
    Filed: August 11, 1995
    Date of Patent: December 24, 1996
    Assignee: Fuji Electric Co., Ltd.
    Inventors: Kazunori Oyabe, Kazuhiko Yoshida, Tatsuhiko Fujihira
  • Patent number: 5570008
    Abstract: For compensating the Early effect a band gap reference voltage source includes current mirror circuits (T.sub.4, Q.sub.3 and T.sub.1, Q.sub.1 as well as T.sub.2, Q.sub.2) to ensure that the currents necessary for achieving the temperature-compensated output voltage are generated. Using the current mirror circuits makes the reference voltage source independent of changes in the supply voltage (U.sub.cc) and enables it in particular to be employed at supply voltages as of low as 3 V.
    Type: Grant
    Filed: April 14, 1994
    Date of Patent: October 29, 1996
    Assignee: Texas Instruments Deutschland GmbH
    Inventor: Laszlo Goetz
  • Patent number: 5563760
    Abstract: A temperature sensing circuit (100) for sensing the temperature of an active semiconductor device, for example, a power MOSFET (11) of a semiconductor body (10). The circuit has a first temperature sensing device (R1R2) provided on the semiconductor body at a first position (P.sub.1) adjacent a periphery (12) of the active semiconductor device (11), a second temperature sensing device (R3,R4) provided on the semiconductor body at a second position (P.sub.2) further from the periphery of the active semiconductor device than the first position. An arrangement, for example, a comparator responsive to the first and second temperature sensing devices provides a control signal to switch off the active semiconductor device (11) when the difference in the temperature sensed by the first and second sensing devices reaches a predetermined value.
    Type: Grant
    Filed: September 16, 1991
    Date of Patent: October 8, 1996
    Assignee: U.S. Philips Corporation
    Inventors: Royce Lowis, Edward S. Eilley, Paul T. Moody, Aart G. Korteling, Brendan P. Kelley
  • Patent number: 5545977
    Abstract: In a circuit, a resistance element is interposed between a positive power supply line (external power supply voltage level VCC) and an output node. To feedback an output potential, there is disposed an N-type MOSFET of which gate is connected to the output node and of which source is connected to the earth line (earth potential VSS) in the circuit. Another three N-type MOSFETs which are so connected in series to one another as to form a MOS diode, are interposed between the drain of the feedback N-type MOSFET and the output node. The earth line also serves as a reference potential line for the potential of the output node. Variations of the threshold voltages of the MOSFETs due to temperature variations are compensated. This restrains the output potential from varying.
    Type: Grant
    Filed: June 9, 1993
    Date of Patent: August 13, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Toshio Yamada, Akinori Shibayama, Shunichi Iwanari, Atsushi Fujiwara
  • Patent number: 5532579
    Abstract: A reference voltage generator includes a current mirror circuit connected to a power supply voltage and having a plurality of transistors which are coupled in parallel to the power supply voltage, a reference current circuit connected between the current mirror circuit and a ground for generating a reference current in accordance with an differential operation, a feedback circuit for applying the reference current to the current mirror circuit, and a constant voltage circuit having an operational amplifier whose input terminal is connected to the current mirror circuit for generating the reference voltage.
    Type: Grant
    Filed: July 7, 1994
    Date of Patent: July 2, 1996
    Assignee: Goldstar Electron Co., Ltd.
    Inventor: Seung K. Park
  • Patent number: 5521489
    Abstract: An overheat detecting circuit for detecting overheating of an integrated circuit has a band gap voltage source circuit for emitting a substantially constant voltage, which is connected between a positive power source line and a reference power source line. The voltage output from the band gap voltage source circuit is independent of the power source voltages and the ambient temperature. A constant current source circuit is provided for generating a constant current according to the output of the band gap voltage source circuit. At least one circuit element is connected between an output terminal of the constant current source circuit and the reference power source line. The circuit element has a predetermined temperature coefficient. A comparator compares the output voltage of the band gap voltage source circuit with that of the circuit element.
    Type: Grant
    Filed: August 31, 1994
    Date of Patent: May 28, 1996
    Assignee: NEC Corporation
    Inventor: Ikuo Fukami
  • Patent number: 5519313
    Abstract: A temperature-compensated voltage regulator includes a field effect transistor voltage buffer which receives a high-voltage input and provides a low-voltage output, and a voltage generator having a series connection of a zener diode and at least one p-n junction diode for generating a reference voltage. The voltage generator is coupled between the low-voltage output of the voltage buffer and the input of a current mirror, with the output of the current mirror being coupled to the gate electrode of the field effect transistor in the voltage buffer. Additionally, the output of the current mirror is coupled to the low-voltage output of the voltage buffer by a resistor. The resulting voltage regulator circuit features high performance in a simple, economical configuration.
    Type: Grant
    Filed: April 6, 1993
    Date of Patent: May 21, 1996
    Assignee: North American Philips Corporation
    Inventors: Stephen L. Wong, Sreeraman Venkitasubrahmanian
  • Patent number: 5517103
    Abstract: A circuit for providing a reference current comprises first and second matched transistors, each of which has a control node and a controllable path and each of which is connected so that a current setting resistor is in the controllable path of the second matched transistor, the current setting resistor having a value, current set in the controllable path of the second matched transistor is related to a difference in voltage characteristics between the first and second matched transistors and to the value of the current setting resistor, and third and fourth matched transistors, each of the third and fourth matched transistors having a controllable path connected respectively to the controllable paths of the first and second matched transistors, and control electrodes of the third and fourth matched transistors connected together; a set of output transistors connected to the circuit to supply the reference current in dependence on a set current; and a fifth transistor having a controllable path between a bia
    Type: Grant
    Filed: August 12, 1993
    Date of Patent: May 14, 1996
    Assignee: SGS Microelectronics, PTE Ltd.
    Inventors: Solomon K. Ng, Gee H. Loh
  • Patent number: 5514948
    Abstract: A constant current is produced by a first MOSFET of depletion type whose source and gate are interconnected and then is passed through a current mirror circuit made up of MOSFETs of the opposite conduction type with respect to the first MOSFET and to a second MOSFET which has the same conduction type as the first MOSFET and whose gate and drain are interconnected. The voltage between the gate and the source of the second MOSFET is taken as an output constant voltage, which is temperature-compensated by the current ratio of the current mirror circuit.
    Type: Grant
    Filed: September 1, 1993
    Date of Patent: May 7, 1996
    Assignee: Hitachi, Ltd.
    Inventor: Takao Okazaki
  • Patent number: 5512817
    Abstract: A bandgap voltage generator using a simple bandgap voltage reference supply circuit which has virtually no power supply rejection ratio (PSRR) which can produce an output bandgap voltage, V.sub.BG, using an extremely low power supply voltage, V.sub.DD. In order to increase the PSRR, a signal generated by the bandgap voltage reference supply circuit is amplified by a high gain amplifier circuit comprised of two cascode connected FETs. The highly amplified signal generated by the high gain amplifier circuit drives a voltage regulator, comprised of an FET used as a voltage controlled current sink, which regulates the voltage supplied from the power supply, V.sub.DD, to the bandgap voltage reference supply circuit. This combination of a bandgap voltage reference with virtually no PSRR and a high gain amplifier results in a bandgap voltage generator with a very high PSRR.
    Type: Grant
    Filed: December 29, 1993
    Date of Patent: April 30, 1996
    Assignee: AT&T Corp.
    Inventor: Krishnaswamy Nagaraj
  • Patent number: 5506494
    Abstract: A resistor circuit includes a pair of linear conductive films and a resistive film. The resistive film is formed on an area between the conductive films and electrically connected to the conductive films. A pair of terminals are electrically connected to portions of the conductive films respectively. A current source is electrically connected between the terminals to deliver an electrical current thereto. A pair of voltage output terminals are electrically connected to portions of the conductive films respectively. At least one of the voltage output terminals is disposed at a portion of the conductive films other than a portion at which the terminals are formed. An output voltage from the voltage output terminals is exactly proportional to a current flowing between them independent of changes in an ambient temperature. The circuit may be implemented in an integrated circuit environment using, e.g., multiple thin film resistors.
    Type: Grant
    Filed: September 13, 1993
    Date of Patent: April 9, 1996
    Assignee: Nippondenso Co., Ltd.
    Inventors: Hajime Ito, Takashi Nagasaka
  • Patent number: 5493154
    Abstract: An improved temperature control system for a power conversion circuit having two or more power converters operating in parallel and providing output power to a single load. The temperature control system maintains the temperature of each of these power converters at approximately the average temperature of the power converters. A detector coupled to each power converter detects the temperature of the power converter and generates a measurement signal that is a function thereof. A reference signal is generated that is a function of each measurement signal. A control circuit responsive to the measurement signal of each power converter adjusts the output power of that respective converter as a function of the difference between that converter's measurement signal and the reference signal such that the temperature of each power converter approximates the average of temperature of the power converters.
    Type: Grant
    Filed: April 21, 1993
    Date of Patent: February 20, 1996
    Assignee: Astec International, Ltd.
    Inventors: David A. Smith, Neal G. Stewart, Carl E. Arvidsson
  • Patent number: 5488288
    Abstract: The present invention relates to a circuit arrangement integrated in a semiconductor circuit. In modern microprocessor systems with high clock rates (50 MHz and more) special chips with narrow tolerance ranges as regards their switching speed are required. The circuit arrangement according to the invention compensates the switching speed fluctuations due to temperature fluctuations and process spread by generating an internal operating voltage and controlling said voltage in such a manner that it counteracts the fluctuations of the switching speed due to temperature changes and process spread and compensates said fluctuations.
    Type: Grant
    Filed: November 12, 1992
    Date of Patent: January 30, 1996
    Assignee: Texas Instruments Deutschland GmbH
    Inventor: Werner Elmer
  • Patent number: 5479092
    Abstract: A correction circuit (12) for providing an error correction voltage for a voltage reference (11). The voltage reference (11) provides a reference voltage within a predetermined temperature range. The voltage reference prior to correction has a peak magnitude at a temperature T.sub.0 within the predetermined temperature range. A first circuit (13) generates a correction current. Zero current is provided by the first circuit (13) at T.sub.0. A second circuit (14) receives the correction current and provides an output current that is uni-directional or of the same sense above and below T.sub.0. [Means responsive to t] The output current of the second circuit (14) generates a voltage across a resistor (28) that is [combined] added to the reference voltage above and below T.sub.0.
    Type: Grant
    Filed: February 13, 1995
    Date of Patent: December 26, 1995
    Assignee: Motorola, Inc.
    Inventors: John M. Pigott, Robert B. Jarrett, Byron G. Bynum
  • Patent number: 5471131
    Abstract: The analog to digital converter 300 has voltage reference circuitry 326 which includes a bandgap generator and a correction circuit 5300. The bandgap generator includes first and second NPN transistors 5211-5224, 5231-5232 of differing emitter areas and an operational amplifier 5202 with inputs sensing the collector current of the first and second NPN transistors 5211-5224, 5231-5232. First and second NPN transistors 5211-5224, 5231-5232 have their bases tied together. The output of the amplifier 5202 drives the bases of the NPN transistors 5211-5224, 5231-5232 through a resistor divider 5251-5253.
    Type: Grant
    Filed: August 9, 1994
    Date of Patent: November 28, 1995
    Assignee: Harris Corporation
    Inventors: Ken R. King, David W. Riemer, Gerald M. Cotreau
  • Patent number: 5455504
    Abstract: A constant-current circuit is disclosed which is arranged such that the magnitude and temperature characteristic of a current flowing through a load can be set independently. Output side of a temperature characteristic setting circuit (15A) connected to a band-gap reference circuit (14), and output side of voltage-follower circuit (16) are connected to a control resistor (R12). The temperature characteristic of the current I0 flowing through the load (13) is set by the band-gap reference circuit (14) and temperature characteristic setting circuit (15A), and the magnitude of the current I0 is set by the control resistor (R12). The arrangement is made such that the magnitude and temperature characteristic of the current I0 can be set independently; thus, the circuit design can be simplified and the the magnitude and temperature characteristic of the current can be set with a high accuracy.
    Type: Grant
    Filed: September 14, 1994
    Date of Patent: October 3, 1995
    Assignee: Toko, Inc.
    Inventors: Kozo Suzuki, Takashi Nagaiwa
  • Patent number: 5450004
    Abstract: A voltage generating device is capable of generating a voltage which does not depend upon temperature even if a power source voltage is not higher than 1.25 V. The device comprises an output terminal thereof, current sources, resistors and a diode like connected transistor. A voltage on the output terminal is obtained by causing a current to flow through series-connected resistors. The current sources are band gap current sources. The current source is assumed as opened. A part of the diode like connected transistor is represented by an equivalent circuit including a voltage source and a resistor. The equivalent circuit and the resistors are represented by an equivalent circuit by using the Thevenin's theorem.
    Type: Grant
    Filed: March 29, 1994
    Date of Patent: September 12, 1995
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventor: Masaharu Ikeda
  • Patent number: 5440520
    Abstract: The specification describes an integrated circuit device that selects its own supply voltage by controlling a programmable power supply. The programmable power supply provides a supply voltage in response to one or more voltage control signals generated by the integrated circuit device. The integrated circuit device includes a voltage control circuit for generating the voltage control signals according to one or more predetermined operational voltages programmed into the integrated circuit device such that the supply voltage is substantially equal to a selected one of the predetermined operational voltages. The integrated circuit device may include a temperature sensor to allow selection of the predetermined operational voltage according to device temperature to avoid speed-limiting voltage and temperature combinations.
    Type: Grant
    Filed: September 16, 1994
    Date of Patent: August 8, 1995
    Assignee: Intel Corporation
    Inventors: Joseph D. Schutz, Bill C. Rash
  • Patent number: 5434533
    Abstract: In a reference voltage generating circuit having an improved temperature compensation function, a PMOS transistor forming a constant voltage circuit has the same characteristics as a PMOS transistor forming a negative feedback circuit. As an ambient temperature changes, gate-source voltage and drain current characteristics of each transistor are shifted, but temperature compensation is achieved by appropriately setting a drain current of each transistor. Transistors for the temperature compensation can be formed in the same manufacturing steps, so that temperature compensating effect can be obtained without an additional manufacturing step.
    Type: Grant
    Filed: December 31, 1992
    Date of Patent: July 18, 1995
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Kiyohiro Furutani
  • Patent number: 5430367
    Abstract: A band-gap voltage regulator having a self-regulating characteristic which improves the operation of the regulator includes a feedback circuit coupling a gain stage of the regulator to a voltage reference circuit which influences the regulated voltage. Changes in the operation of the gain stage which would otherwise change the regulated voltage produce counteracting changes in the voltage reference circuit, causing the supply voltage to remain substantially constant.
    Type: Grant
    Filed: January 19, 1993
    Date of Patent: July 4, 1995
    Assignee: Delco Electronics Corporation
    Inventors: William P. Whitlock, Mark B. Kearney
  • Patent number: 5428287
    Abstract: An overcurrent limit circuit in which the output transistor and current sense transistor share a common collector and common base. A reference voltage is compared with a voltage derived from a current sense resistor. The circuit limits the current to the base of the output transistor in response to the reference voltage threshold being reached at the current sense resistor. A Vbe comparator comprised of two transistors may be used with a first bias current to both transistors and a second bias current to one of the two transistors.
    Type: Grant
    Filed: September 12, 1994
    Date of Patent: June 27, 1995
    Assignee: Cherry Semiconductor Corporation
    Inventor: Dan Agiman
  • Patent number: 5424628
    Abstract: A bandgap reference circuit (14) in a bandgap voltage reference device (10) generates a bandgap voltage reference (V.sub.BG) at the base of a Q1 transistor (22) and a Q2 transistor (20). A reference current signal I.sub.T flows into the collectors of the Q2 transistor (20) and the Q1 transistor (22) as generated by a difference in base to emitter voltages due to a difference in emitter areas between the Q2 transistor (20) and the Q1 transistor (22). A correction current signal (I.sub.TT) generated by a current squaring circuit (16) is injected into the collector of the Q1 transistor (22) such that the collectors of the Q2 transistor (20) and the Q1 transistor (22) have unequal current values. The current squaring circuitry (16) generates the correction current signal (I.sub.TT) by squaring the reference current signal (I.sub.T) and dividing it into a sampling current signal (I.sub.SC ) generated in a current generator amplifier (18).
    Type: Grant
    Filed: April 30, 1993
    Date of Patent: June 13, 1995
    Assignee: Texas Instruments Incorporated
    Inventor: Baoson Nguyen
  • Patent number: 5408174
    Abstract: A current reference using a switched capacitor to produce a substantially temperature invariant output current. Charge subtracted from a relatively large capacitor by a much smaller switched capacitor at a chosen rate substantially determines the output current of the reference. The output current is proportional to the product of a reference voltage, the capacitance of the switched capacitor and the switching frequency.
    Type: Grant
    Filed: June 25, 1993
    Date of Patent: April 18, 1995
    Assignee: AT&T Corp.
    Inventor: Robert H. Leonowich
  • Patent number: 5394078
    Abstract: A two terminal temperature transducer which controls its operating current to indicate the temperature, by producing a linear response to temperature which can be set to extrapolate to a desired temperature. The transducer including circuitry which controls its operating current to be linearly proportional with temperature. The circuitry operates to produce a first reference voltage which is proportional to absolute temperature, produce a second reference voltage which is complementary to absolute temperature, generate a voltage drop corresponding to the operating current, compare the voltage drop to a temperature sensitive voltage corresponding to the difference between the first reference voltage and the second reference voltage, and adjust the operating current so as to equilibrate the voltage drop and the temperature sensitive voltage.
    Type: Grant
    Filed: October 26, 1993
    Date of Patent: February 28, 1995
    Assignee: Analog Devices, Inc.
    Inventor: A. Paul Brokaw
  • Patent number: 5391980
    Abstract: A voltage reference circuit (2) is provided which includes a 2nd order curvature correction circuit (3) that eliminates undesirable 2nd order polynomial temperature dependency characteristics. A bandgap reference circuit (Q4, Q3, Q2, Q1, R2 and R1) forms a bandgap current (I.sub.X) that is dependent upon absolute temperature. A translinear cell (Q15, Q14, Q13, Q12, Q11 and Q10) transforms this current in a squaring transformation and divides the squared current by a temperature independent current (I.sub.X). A current mirror (Q17 and Q16) adjusts the value of the squared current so that it approximates the value of the 2nd order term of the bandgap reference circuit.
    Type: Grant
    Filed: June 16, 1993
    Date of Patent: February 21, 1995
    Assignee: Texas Instruments Incorporated
    Inventors: Frank L. Thiel, Baoson Nguyen
  • Patent number: 5384529
    Abstract: A current limiting circuit which includes a vertical MOS transistor as an output transistor has a clamping voltage that can be established with high accuracy, and once established, is less dependent on temperature. The gate of an output N-channel VDMOS transistor is connected to a constant-voltage circuit composed of an N-channel VDMOS transistor having the same characteristics as those of the output N-channel VDMOS transistor and two series-connected resistors which supply a divided voltage to the gate of the N-channel VDMOS transistor. The clamping voltage between the gate and source of the output N-channel VDMOS transistor can be adjusted based on the voltage divided by the resistors of the constant-voltage circuit. The temperature characteristics of the output N-channel VDMOS transistor and the constant-voltage circuit are held in phase with each other to reduce variations in the clamping voltage caused by temperature variations.
    Type: Grant
    Filed: January 28, 1994
    Date of Patent: January 24, 1995
    Assignee: NEC Corporation
    Inventor: Manabu Nakago
  • Patent number: 5373205
    Abstract: A method and apparatus for limiting current through a switching device supplying current to a load. A control evaluates a model representing the switching device temperature as a nonlinear function of current and time. The model compares the temperature of the switching device to a maximum allowable temperature. The current limit is defaulted to peak current; and in response to the model detecting a temperature in excess of the maximum allowable temperature, a nominal current limit is set. The current limit reset to peak current after the model detects a switching device temperature a predetermined magnitude below the maximum allowable temperature.
    Type: Grant
    Filed: December 29, 1992
    Date of Patent: December 13, 1994
    Assignee: Cincinnati Milacron Inc.
    Inventors: Rickey L. Busick, Mark S. Taylor, Stephen T. Walsh
  • Patent number: 5369245
    Abstract: An electronic component is conditioned to remove distortion in a temperature response characteristic due to a temperature hysteresis effect, by subjecting the component to a controlled temperature variation prior to operation of the component at a given temperature. A circuit is disclosed wherein the component is a zener reference element and a bias voltage of cyclical waveform and of reducing magnitude is applied to a control transistor to cause corresponding variation of the temperature of the zener via an on-chip heater. The zener is subsequently operated at a normal bias voltage corresponding to the mean value of the cyclic waveform.
    Type: Grant
    Filed: July 30, 1992
    Date of Patent: November 29, 1994
    Assignee: Metron Designs Ltd.
    Inventor: John R. Pickering
  • Patent number: 5352973
    Abstract: An output curvature correction is provided for a band-gap reference circuit that exhibits a temperature dependent output error in the form of k.sub.1 T - k.sub.2 Tln(k.sub.3 T) in the absence of the correction. A substantially constant collector current is driven through a correction transistor and used in connection with a proportional to absolute temperature (PTAT) transistor collector current in the uncorrected circuit. The difference between the base-emitter voltages for the two transistors has the form -k.sub.1 'T + k.sub.2 'ln(k.sub.3 'T.sub.). This voltage differential is scaled by an appropriate selection of resistor ratios and combined with the uncorrected circuit output to provide a corrected output that is substantially insensitive to temperature variations.
    Type: Grant
    Filed: January 13, 1993
    Date of Patent: October 4, 1994
    Assignee: Analog Devices, Inc.
    Inventor: Jonathan M. Audy
  • Patent number: 5350998
    Abstract: A circuit for temperature compensating the inverse saturation current of a bipolar transistor having a collector region, base and emitter regions defining a base-emitter junction is disclosed. A diode element having substantially said same saturation current is parallel-connected in reverse configuration to said base-emitter junction of the bipolar transistor. If the bipolar transistor is NPN type, the diode has an anode and cathode connected respective to the emitter and base regions of the transistor.
    Type: Grant
    Filed: April 23, 1992
    Date of Patent: September 27, 1994
    Assignee: SGS-Thomson Microelectronics S.r.l.
    Inventors: Fabio Marchio, Enrico Novarini, Giorgio Rossi
  • Patent number: 5341287
    Abstract: A device and process for the control of a magnitude x by action on a control magnitude y is disclosed. Magnitude x has a one-to-one relationship with magnitude y when the value of a parameter h remains constant. Magnitude x is sensitive to and a one-to-one function of parameter h. Parameter h varies in a predetermined interval h.sub.m to h.sub.M, including reference value h.sub.i. A function y.sub.p =g.sub.p (h), which is the value given to the magnitude y to obtain the value x.sub.p when the parameter has a value h, can be defined for each value x.sub.p. The different functions g.sub.p (h) have a property wherein the value of a second function g'.sub.p (h) can be determined from the value of function g.sub.p (h) having the same value of parameter h, by the addition of a function of the difference between the real measured value h.sub.r and the reference value h.sub.i. Magnitude x is represented by the output magnitude of an operational amplifier having first and second inputs.
    Type: Grant
    Filed: August 12, 1992
    Date of Patent: August 23, 1994
    Assignee: Thomson-CSF
    Inventors: Joel Cordier, Laurent Cariou
  • Patent number: 5334929
    Abstract: An integrated circuit for providing a current proportional to absolute temperature comprises circuitry for providing a first current exhibiting substantially zero temperature coefficient; circuitry for providing a second current exhibiting a negative temperature coefficient; and circuitry for summing the first and second currents for providing a third current proportional to absolute temperature.
    Type: Grant
    Filed: August 26, 1992
    Date of Patent: August 2, 1994
    Assignee: Harris Corporation
    Inventor: Otto H. Schade, Jr.
  • Patent number: 5315230
    Abstract: A reference voltage generator which compensates for temperature and V.sub.CC variations includes a constant current source and a MOS P-channel transistor. The constant current source provides a constant current over a wide range of V.sub.CC that corresponds to biasing a p-channel transistor in a region where its resistance is constant. The output of the current source is supplied to the P-channel transistor, which is in saturation. The constant current provides a constant voltage drop across the P-channel transistor. Hence, a stable reference voltage is generated. Temperature compensation is provided by biasing the P-channel transistor to saturation and supplying a constant current that the corresponds to biasing a p-channel transistor where the resistance is substantially constant over a temperature range. The current causes a voltage drop across the P-channel transistor to maintain a stable reference voltage.
    Type: Grant
    Filed: September 3, 1992
    Date of Patent: May 24, 1994
    Assignees: United Memories, Inc., Nippon Steel Semiconductor Corp.
    Inventors: Michael V. Cordoba, Kim C. Hardee, Douglas B. Butler
  • Patent number: RE34772
    Abstract: A stable reference voltage generator using a current mirror circuit comprising a primary branch and a secondary branch, is shown and described. A first bipolar transistor (Q1) has its collector connected in series with the primary branch of the current mirror, and a voltage divider bridge comprising at least two series-connected resistors (R1, R2), is connected in series between the secondary branch of the current mirror and the collector of a second bipolar transistor (Q2). The base of the second transistor (Q2) is connected to the common point of the series resistors, the base of the first transistor (Q1) is connected to the collector of the second transistor (Q2), and the output of the generator (V.sub.REF) is connected to the terminal of the bridge opposite that connected to the collector of the second transistor (Q.sub.2). The geometry of said transistors being such that the first transistor (Q1) is equivalent to "N" transistors identical to the second transistor (Q2) connected in parallel.
    Type: Grant
    Filed: May 7, 1993
    Date of Patent: November 1, 1994
    Assignee: SGS-Thomson Microelectronics, S.A.
    Inventors: Patrick Bernard, Christophe Magnier