Temperature Compensation Of Semiconductor Patents (Class 323/907)
  • Patent number: 7692418
    Abstract: A BGR circuit includes a temperature-proportional current generating part configured to generate a current in proportion to a change in temperature through a plurality of current paths; a temperature-inverse proportional current generating part generates a current in inverse proportion to a change in temperature through a plurality of current paths. An internal voltage reference voltage generating part generates a reference voltage for an internal voltage using the current of the temperature-proportional current generating part and the current of the temperature-inverse proportional current generating part. A temperature voltage output part outputs a voltage corresponding to a change in temperature.
    Type: Grant
    Filed: December 29, 2006
    Date of Patent: April 6, 2010
    Assignee: Hynix Semiconductor, Inc.
    Inventor: Chun-Seok Jeong
  • Patent number: 7688054
    Abstract: A temperature corrected voltage bandgap circuit is provided. The circuit includes first and second diode connected transistors. A first switched current source is coupled to the one transistor to inject or remove a first current into or from the emitter of that transistor. The first current is selected to correct for curvature in the output voltage of the bandgap circuit at one of hotter or colder temperatures.
    Type: Grant
    Filed: June 2, 2006
    Date of Patent: March 30, 2010
    Inventor: David Cave
  • Patent number: 7683955
    Abstract: A photocurrent sensing circuit includes a logarithmic compression circuit; a cancellation circuit logarithmically compressing a current substantially equal in temperature coefficient of the photocurrent to convert the same into a voltage, and performing an addition or a subtraction on the converted voltage and a voltage converted from a photocurrent by logarithmically compression; a logarithmic operation circuit logarithmically compressing the voltage received from the cancellation circuit to produce a first voltage, logarithmically compressing a voltage proportional to a thermal voltage of the photocurrent to produce a second voltage, logarithmically compressing a current having thermal dependence of nearly zero to produce a third voltage and performing an addition or a subtraction of each of the second and third voltages with respect to the first voltage to produce a fourth voltage; and an inverse logarithmic transformation circuit performing inverse logarithmic transformation on the fourth voltage to outpu
    Type: Grant
    Filed: October 15, 2007
    Date of Patent: March 23, 2010
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Takayuki Shimizu
  • Patent number: 7659706
    Abstract: A current detector circuit for detecting a load current flowing through a load includes a first series circuit having a first element and the load connected in series, a second series circuit having a second element and a resistor connected in series, the second element having a temperature characteristic equal to the temperature characteristic of the resistance of the first element, a power supply configured to supply voltage to the first series circuit and the second series circuit, and a control circuit configured to control the voltage drop across the second element so that the voltage drop across the second element is equal to the voltage drop across the first element. A current detection signal corresponding to the load current is generated based on a current flowing through the second element.
    Type: Grant
    Filed: March 5, 2007
    Date of Patent: February 9, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Junji Nishida
  • Patent number: 7642759
    Abstract: Circuits and methods for paralleling voltage regulators are provided. Improved current sharing and regulation characteristics are obtained by coupling control terminals of the voltage regulators together which results in precise output voltages and proportional current production. Distributing current generation among multiple paralleled voltage regulators improves heat dissipation and thereby reduces the likelihood that the current produced by the voltage regulators will be temperature limited.
    Type: Grant
    Filed: July 13, 2007
    Date of Patent: January 5, 2010
    Assignee: Linear Technology Corporation
    Inventor: Robert C. Dobkin
  • Patent number: 7629785
    Abstract: A system includes a transistor coupled to a voltage rail, a first resistor coupled in series with the transistor, and a second resistor coupled in series with the first resistor. The system also includes a bandgap reference circuit operable to generate a bandgap reference voltage of less than 1.2 volts (such as one volt) between the first and second resistors. The bandgap reference circuit includes a diode configured to generate a complementary-to-absolute-temperature (CTAT) voltage and a third resistor configured to generate a first proportional-to-absolute-temperature (PTAT) voltage using a first current. The bandgap reference circuit also includes a current source configured to sink a CTAT current from the first current to generate a second current and a fourth resistor configured to generate a second PTAT voltage using the second current. A sum of the CTAT voltage, the first PTAT voltage, and the second PTAT voltage is less than 1.2 volts.
    Type: Grant
    Filed: May 23, 2007
    Date of Patent: December 8, 2009
    Assignee: National Semiconductor Corporation
    Inventor: Stephan Drebinger
  • Patent number: 7609045
    Abstract: The present invention concerns a reference voltage generator (40) that provides a reference voltage (Vref new). The voltage generator (30) is operated at a supply voltage (Vdd) being lower than the Silicon bandgap voltage. It comprises a MOSFET transistor (MN; MN3; MP4; MP7) serving as transconductor (Gptat). An input node for feeding a drain current (Iptat) into the drain of said MOSFET transistor (MN; MN3; MP4; MP7) is provided and an output node is connected to the drain and gate of said MOSFET transistor (MN; MN3; MP4; MP7). A current generator (42) allows the MOSFET transistor (MN; MN3; MP4; MP7) to be operated in a specific mode where the drain current (Iptat) has a positive temperature coefficient (?ptat) and the transconductor (Gptat) has a negative temperature coefficient (?ptat).
    Type: Grant
    Filed: December 1, 2005
    Date of Patent: October 27, 2009
    Assignee: NXP B.V.
    Inventor: Zhenhua Wang
  • Patent number: 7535735
    Abstract: Techniques to compensate for parameter variations in a feedback circuit are disclosed. In one embodiment, a regulator circuit includes an energy source coupled to output a generated current in response to a control current. A feedback resistor is coupled to an output of the regulator circuit. The feedback resistor is coupled to conduct a feedback current responsive to the output of the regulator circuit. A current amplifier is coupled to the feedback resistor to generate the control current in response to the feedback current. A compensation network is coupled to the current amplifier to adjust the control current in response to an extrinsic parameter of the regulator circuit. The compensation network includes a transistor and first, second and third resistors. The first resistor is coupled between the feedback resistor and a collector of the transistor. The second resistor coupled between the collector and the base of the transistor.
    Type: Grant
    Filed: September 13, 2004
    Date of Patent: May 19, 2009
    Assignee: Power Integrations, Inc.
    Inventors: Jason E. Cuadra, Arthur B. Odell, William Michael Polivka
  • Patent number: 7531998
    Abstract: A temperature sensing circuit includes first, second and third proportional to absolute temperature (PTAT) units, and first and second subtracters. The first PTAT unit generates a first output voltage based on a reference current and a current of N times the reference current, where N is an emitter current density ratio. The second PTAT unit generates a second output voltage based on a current of twice the reference current and a current of 2N times the reference current. The third PTAT unit generates a third output voltage based on the reference current and a current of N times the reference current. The first subtracter performs subtraction on the second output voltage and the third output voltage, and the second subtracter performs subtraction on an output voltage of the first subtracter and the first output voltage.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: May 12, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Hyung-seuk Kim
  • Patent number: 7532056
    Abstract: A temperature sensor includes a proportional to absolute temperature (PTAT) current generator configured to generate a first current proportional to temperature, a first complementary to absolute temperature (CTAT) current generator configured to generate a second current inversely proportional to temperature, a second CTAT current generator configured to generate a third current inversely proportional to temperature, and a temperature sensing unit configured to convert the first current, the second current, and the third current into a signal related to the temperature.
    Type: Grant
    Filed: July 21, 2006
    Date of Patent: May 12, 2009
    Assignee: Samsung Electronics Co., Ltd.
    Inventor: Young-Hun Seo
  • Patent number: 7504813
    Abstract: A power detector having temperature compensation for improved measurement performance includes a pair of rectifier transistors coupled to a differential input signal biased by a first temperature dependent current. An output of the pair of rectifier transistors provides a first component of a differential DC output signal. The first component of the differential DC output signal includes a DC voltage proportional to an amplitude of the differential input signal plus an offset voltage. The power detector further includes a reference transistor biased by a reference current. The reference current includes a second temperature dependent current and a temperature independent offset current for temperature compensation. An output of the reference transistor provides a second component of the differential DC output signal that includes a reference voltage.
    Type: Grant
    Filed: October 17, 2005
    Date of Patent: March 17, 2009
    Assignee: Broadcom Corporation
    Inventor: Danilo Manstretta
  • Patent number: 7495426
    Abstract: A temperature setpoint circuit comprises bipolar transistors Q1 and Q2 which receive currents I1 and I2 at their respective collectors and are operated at unequal current densities, with a resistance R1 connected between their bases such that the difference in their base-emitter voltages (?Vbe) appears across R1. An additional PTAT current I3 is maintained in a constant ratio to I1 and I2 and provided to the collector of Q2 while Q2 is off, and is not provided while Q2 is on. The circuit is arranged such that Q2 is turned on and conducts a current equal to Ia when: ?Vbe=(kT/q)ln(NI1/Ia), where Ia=I2+I3, the temperature T at which ?Vbe=(kT/q)ln(NI1/Ia) being the circuit's setpoint temperature, such that the switching of current I3 provides hysteresis for the setpoint temperature which is approximately constant over temperature.
    Type: Grant
    Filed: March 6, 2006
    Date of Patent: February 24, 2009
    Assignee: Analog Devices, Inc.
    Inventors: Chau C. Tran, A. Paul Brokaw
  • Patent number: 7486065
    Abstract: The present invention is directed to a device and method for generating a reference voltage. A reference voltage generator comprises a first circuit, a second circuit, and an external device. The first circuit generates a positive temperature coefficient voltage. the second circuit is coupled to the first circuit, biased with a substantially constant current, produces a negative temperature coefficient voltage, and combines the negative temperature coefficient voltage with the positive temperature coefficient voltage as a reference voltage. The external device is coupled to the second circuit, and yields the substantially constant current.
    Type: Grant
    Filed: September 9, 2005
    Date of Patent: February 3, 2009
    Assignee: VIA Technologies, Inc.
    Inventors: Jyh-Fong Lin, Pei-Hsiu Huang
  • Patent number: 7472030
    Abstract: In a system for performing a dual mode single temperature trim upon an electronic device to remove combined mismatch and process variation errors, a dynamic element matching control is configured for enabling dynamic element matching of components of the electronic device. A process trim module is configured for performing a process trim to remove a temperature dependant error from the electronic device while the dynamic element matching is enabled within the electronic device. A mismatch trim module is configured for performing a mismatch trim to remove a mismatch error from the electronic device after the process trim has been performed. The mismatch trim is performed on a portion of the electronic device for which the dynamic element matching has been disabled. Additionally, the mismatch trim is performed at substantially an equivalent temperature to a temperature at which the process trim was performed.
    Type: Grant
    Filed: August 4, 2006
    Date of Patent: December 30, 2008
    Assignee: National Semiconductor Corporation
    Inventor: Eric Scheuerlein
  • Patent number: 7469174
    Abstract: A constant-voltage power supply circuit unit that is fed from a vehicle-borne battery via a power switch and generates a predetermined constant-voltage output Vcc includes a power transistor and an output voltage regulating circuit unit. The output voltage regulating circuit unit includes a reference voltage generating circuit, a comparison amplifying circuit, a resistance circuit network, a non-volatile second data memory that selectively continues plural open/close elements provided in the resistance circuit network, and a temperature detector. The quantity of variation of output voltage with respect to ambient temperature detected by the temperature detector is estimated, and a setting voltage is corrected to be approximate to a predetermined output voltage, or conversion correction of AD conversion data is performed on the basis of voltage variation characteristics of an analog sensor.
    Type: Grant
    Filed: December 20, 2005
    Date of Patent: December 23, 2008
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Yuki Iwagami, Manabu Yamashita, Kohji Hashimoto
  • Patent number: 7429719
    Abstract: A self-regulating heater including a semiconductor for converting electrical energy to heat. A temperature sensitive element is used to bias the semiconductor as a function of temperature. The heating element has an advantage that its maximum temperature is limited by the biasing network, yet full power is available just below the limit.
    Type: Grant
    Filed: August 11, 2006
    Date of Patent: September 30, 2008
    Assignee: Stellar Systems, Inc.
    Inventor: William L Spetz
  • Patent number: 7411380
    Abstract: A non-linearity compensation circuit and a bandgap reference circuit using the same for compensating non-linear effects of a reference voltage are provided. In the non-linearity compensation circuit, the reference voltage is transformed into a temperature independent current. A current mirror mirrors the temperature independent current for biasing a bipolar junction transistor (BJT). Further, two resistors are used for estimating a non-linear voltage, so as to compensate the reference voltage.
    Type: Grant
    Filed: July 21, 2006
    Date of Patent: August 12, 2008
    Assignee: Faraday Technology Corp.
    Inventors: Kuen-Shan Chang, Uei-Shan Uang
  • Patent number: 7405547
    Abstract: A stabilized DC power supply circuit of the present invention includes an output current limiting circuit for limiting an output current of an output transistor, and a correction circuit for correcting variation of restriction in the output current caused by variation in a current amplification factor of the output transistor. The correction circuit includes a correcting transistor that is manufactured in the same manufacturing process as the output transistor and formed so as to have the same tendency of manufacturing process variation in current amplification factor etc. as that of the output transistor.
    Type: Grant
    Filed: May 1, 2006
    Date of Patent: July 29, 2008
    Assignee: Sharp Kabushiki Kaisha
    Inventor: Takao Kanzaki
  • Patent number: 7345460
    Abstract: A device and method of providing thermal compensation for integrated circuits, e.g., complementary metal-oxide semiconductor integrated circuits (“IC”) is described. The device is an IC (e.g., digital, analog, and mixed-signal circuits) with a digital voltage control system (“VCS”) having a temperature-adaptive digital DC-to-DC power converter. In one embodiment, the DC-to-DC converter includes a power stage, which converts a voltage of an input power source to a variable supply voltage, a delay-line-based temperature sensing circuit that continuously monitors temperature changes, and adjusts the frequency and process speed of the IC to compensate for any performance degradation caused by thermal effects by adjusting the voltage supplied to the IC to increase or decrease the frequency and process speed of the IC in proportion to any abnormal temperature changes in the IC.
    Type: Grant
    Filed: February 24, 2006
    Date of Patent: March 18, 2008
    Assignee: Board of Supervisors of Louisiana State University and Agricultural and Mechanical College
    Inventors: Dongsheng Ma, Chuang Zhang
  • Patent number: 7327129
    Abstract: In a DC-to-DC converter, a current sense circuit and method generate a first current by a first transconductive amplifier responsive to the output current of the converter for a controller to switch a high side switch and a low side switch, a second current from a first voltage by a second transconductive amplifier, a second voltage from the second current by an adjustable resistor, and a bias signal from a difference between the second voltage and a third voltage by a bias apparatus to adjust the transconductances of the first and second transconductive amplifiers.
    Type: Grant
    Filed: April 6, 2005
    Date of Patent: February 5, 2008
    Assignee: Analog and Power Electronics Corp.
    Inventors: Ming-Hsueh Chen, Ming Chu Chien
  • Patent number: 7315461
    Abstract: An object of this power supply device is to enable an overheat protection level and an overvoltage protection level to be set accurately.
    Type: Grant
    Filed: January 9, 2004
    Date of Patent: January 1, 2008
    Assignee: Sanken Electric Co., Ltd.
    Inventor: Yoichi Kyono
  • Patent number: 7301321
    Abstract: A voltage reference circuit including a positive temperature coefficient current generator, a negative temperature coefficient current generator, and a first resistor is provided. In the positive temperature coefficient current generator, two transistors are operated in the weak inversion region, and a second resistor is connected in series between the gates of the two transistors. The second resistor employs the characteristic that a transistor operated in weak inversion region acts like a bipolar junction transistor to generate a positive temperature coefficient current. The negative temperature coefficient current generator generates a negative temperature coefficient current in response to a negative temperature coefficient voltage drop on a third resistor. The positive temperature coefficient current and the negative temperature coefficient current flow through the first resistor together, thus producing a stable reference voltage.
    Type: Grant
    Filed: September 6, 2006
    Date of Patent: November 27, 2007
    Assignee: Faraday Technology Corp.
    Inventors: Uei-Shan Uang, Kuen-Shan Chang, Mei-Show Chen
  • Patent number: 7282901
    Abstract: A circuit of the invention comprises a low voltage PTAT source. Current generators (t1, t2) are controlled so that their output currents I1 and I2, respectively, have temperature properties of the quotient VPTAT/R. The current I1 is conducted to a first terminal (X) on a first connection of a composition of series connected resistors (Ra, Rb), a second connection thereof being grounded. A transistor (T) is diodelike forward connected between the first terminal (X) and the ground. The current I2 is conducted to a second terminal (Y), preferably being at the same time a common connection (Z) of the resistors (Ra, Rb). Reference voltage Vr is tapped from the connection (Z). Said resistors (Ra, Rb) are manufactured in the n?-well technology in the same way as the resistor (R), with the resistance of which the mentioned quotient is generated.
    Type: Grant
    Filed: July 9, 2003
    Date of Patent: October 16, 2007
    Inventor: Anton Pletersek
  • Patent number: 7274174
    Abstract: In a voltage regulator including an inductor current flowing through a sense element with a first temperature coefficient, and a current sense circuit for generating a current sense signal related to the first temperature coefficient by sensing the inductor current from the sense element, a temperature compensation device and method determines a second temperature coefficient according to the first temperature coefficient and temperature variation, and produces a compensation signal with the second temperature coefficient to compensate variations in the current sense signal caused by the first temperature coefficient.
    Type: Grant
    Filed: September 20, 2005
    Date of Patent: September 25, 2007
    Assignee: Richtek Technology Corp.
    Inventors: Hung-I Wang, Jiun-Chiang Chen
  • Patent number: 7253597
    Abstract: A curvature corrected bandgap reference circuit comprises a first bipolar transistor having a base-emitter voltage Vbe1 and operated such that it has a constant operating current, and a second bipolar transistor having a base-emitter voltage Vbe2 and operated such that it has an operating current consisting of an approximately temperature proportional component and a non-linear component. The circuit is arranged such that the ratio of the current densities in the two transistors varies with temperature, such that the difference voltage (?Vbe=Vbe1?Vbe2) includes a residual component which approximately compensates bandgap curvature error.
    Type: Grant
    Filed: February 23, 2005
    Date of Patent: August 7, 2007
    Assignee: Analog Devices, Inc.
    Inventor: A. Paul Brokaw
  • Patent number: 7208930
    Abstract: A bandgap voltage regulator is arranged such that, when a desired output voltage is present between its output and common terminals, current densities in a pair of bipolar transistors having unequal emitter areas are maintained in a fixed ratio. The difference in the transistors' base-emitter voltages is across a resistor, which thus conducts a PTAT current. The regulator also generates a CTAT current, and both the PTAT and CTAT currents are made to flow in another resistor, with the resulting voltages added by superposition. The regulator's resistors are sized such that Vout is an integral or fractional multiple of Vbg, where Vbg is the bandgap voltage for the fabrication process used to make the regulator's transistors, such that Vout is temperature invariant, to a first order. The resistors are preferably realized using unit resistors having a predetermined resistance, or series and/or parallel combinations of unit resistors.
    Type: Grant
    Filed: January 10, 2005
    Date of Patent: April 24, 2007
    Assignee: Analog Devices, Inc.
    Inventors: Chau C. Tran, A. Paul Brokaw
  • Patent number: 7197419
    Abstract: A system and method are provided for monitoring temperature within a specified integrated circuit. Usefully, the system comprises at least one oscillator device proximate to the integrated circuit for generating signal pulses at a frequency that varies as a function of the temperature adjacent to the oscillator device. The system further comprises a control unit for establishing sample acquisition periods of invariant time duration based on an time invariant reference clock. A sampling component is coupled to count the number of pulses generated by the oscillator device during each of a succession of the time invariant sample acquisition periods, and a threshold component responsive to the respective count values for the succession of sample acquisition periods provides notice when at least some of the count values have a value associated with a prespecified excessive temperature level.
    Type: Grant
    Filed: February 3, 2005
    Date of Patent: March 27, 2007
    Assignee: International Business Machines Corporation
    Inventors: Michael Stephen Floyd, Asher Shlomo Lazarus, Brian Chan Monwai
  • Patent number: 7193402
    Abstract: A bandgap reference voltage circuit is provided, in which an additional resistor as well as a transistor is utilized to prevent the source-drain voltage of a metal oxide semiconductor field effect transistor electrically connected to an output terminal of the bandgap reference voltage circuit from falling into the triode region. Through the provided bandgap reference voltage circuit, the temperature compensation effect is able to be normally executed, so as to supply a stable bandgap reference voltage.
    Type: Grant
    Filed: August 12, 2005
    Date of Patent: March 20, 2007
    Assignee: Analog Integrations Corporation
    Inventors: Jian-Lung Lee, Tsung-Hsiu Wu
  • Patent number: 7166994
    Abstract: A bandgap reference circuit. In the bandgap reference circuit, a current generator includes a first bipolar junction transistor (BJT) and generates a first positive temperature coefficient current thereby producing a negative temperature coefficient voltage between a base terminal and an emitter terminal of the first bipolar junction transistor. A single-end gain amplifier includes a positive input terminal coupled to the emitter terminal of first the bipolar junction transistor. A first resistor is coupled between the output terminal of the single-end gain amplifier and an output terminal of the bandgap reference circuit to generate a first current. A current-to-voltage converter is coupled to the first resistor to convert the first positive temperature coefficient current and the first current to a bandgap voltage.
    Type: Grant
    Filed: December 21, 2004
    Date of Patent: January 23, 2007
    Assignee: Faraday Technology Corp.
    Inventors: Chao-Chi Lee, Wen-Cheng Yen
  • Patent number: 7164259
    Abstract: An apparatus and method for producing an output reference voltage is provided. A voltage divider is configured to provide the output reference voltage from a bandgap reference voltage. The bandgap reference voltage is applied across a biased portion of the voltage divider. Additionally, a second-order temperature coefficient (TC) of the impedance of a controllable portion of the voltage divider is adjusted in response to a second-order trim signal. The first and zeroth order TCs of the controllable portion of the voltage divider are substantially independent of the second-order trim signal. In one embodiment, the controllable portion includes a resistor digital-to-analog converter (DAC) that is responsive to the second-order trim signal. The resistor DAC includes at least two different types of resistors. The second-order TCs of the two different types of resistors are substantially different.
    Type: Grant
    Filed: March 16, 2004
    Date of Patent: January 16, 2007
    Assignee: National Semiconductor Corporation
    Inventors: David James Megaw, Paul Ranucci
  • Patent number: 7161340
    Abstract: A reference voltage generator includes a plurality of signal generators for producing N+1 signals respectively corresponding to N+1 temperature dependent characteristics, a combining module coupled to the signal generators for combining the N+1 signals to form a combined signal, and a signal to voltage converter coupled to the combining module for generating a compensated reference voltage according to the combined signal. The signal generators include N+1 devices having p-n junctions and each device has a specific temperature dependent characteristic corresponding to the voltage across a p-n junction, such as the base-emitter voltage of a transistor. By scaling the N+1 signals, a reference voltage at a predetermined value is generated and has Nth order temperature compensation.
    Type: Grant
    Filed: July 12, 2004
    Date of Patent: January 9, 2007
    Assignee: Realtek Semiconductor Corp.
    Inventor: Yung-Ming Chiu
  • Patent number: 7157893
    Abstract: There is provided a reference voltage generator that generates a constant reference voltage regardless of a change in temperature. The reference voltage generator includes a temperature-compensated current generating part for reducing a supply current provided to an output terminal in response to an increase of temperature, and a diode for receiving the supply current through the output terminal.
    Type: Grant
    Filed: June 29, 2004
    Date of Patent: January 2, 2007
    Assignee: Hynix Semiconductor Inc.
    Inventor: Jong-Chern Lee
  • Patent number: 7126316
    Abstract: A voltage regulation circuit. The voltage regulator includes an input stage, a reference voltage circuit, a gain stage, and an output stage. The reference voltage circuit is coupled to one input of the input stage, and the output stage is coupled to another input of the input stage. The gain stage includes a buffer device coupled to the output of the input stage and a drive circuit coupled to the output stage. The buffer device is operable to provide isolation between the input stage and the drive circuit. The drive circuit may include a first transistor coupled to the output stage, a base current translation circuit, and a current divide circuit coupled to the first transistor and to said base current translation circuit. The input stage may be biased with a substantially constant bias current, such that output dependent current loading effects are avoided.
    Type: Grant
    Filed: February 9, 2004
    Date of Patent: October 24, 2006
    Assignee: National Semiconductor Corporation
    Inventor: Ronald Neal Dow
  • Patent number: 7122998
    Abstract: A system and method is disclosed for providing a bandgap reference voltage generator that can successfully operate with a low operating voltage. Three current sources are controlled to provide same amount of current through three paths. The first current source is used to enable a first negative temperature coefficient module, while the second and third current sources are used to enable a first positive temperature coefficient module. The three current sources together are used to enable a reference voltage output module, which is connected to a current summing module for producing a bandgap reference voltage independent of temperature variations.
    Type: Grant
    Filed: March 19, 2004
    Date of Patent: October 17, 2006
    Assignee: Taiwan Semiconductor Manufacturing Company
    Inventor: Chung-Hui Chen
  • Patent number: 7122997
    Abstract: A temperature compensated low voltage reference circuit can be realized with a reduced operating voltage overhead. This is accomplished in several ways including minimizing drain voltage variation at the drains of two inter-connected transistors and implementing a current conveyer in order to adjust the temperature coefficient of an output current or voltage. Various combinations of voltage minimization and temperature coefficient adjustments may be used to design a reference circuit to a circuit designer's preference. A temperature compensated current source may also be created. The temperature compensated current source may be used to provide a wide range of output voltages. All of the reference circuits may be constructed with various types of transistors including DTMOS transistors.
    Type: Grant
    Filed: November 4, 2005
    Date of Patent: October 17, 2006
    Assignee: Honeywell International Inc.
    Inventor: Paul M. Werking
  • Patent number: 7109697
    Abstract: An operational amplifier having temperature-compensated offset correction. The amplifier includes an operational amplifier circuit, that has a first input field effect transistor (FET) having a gate connected to receive a first input signal, and a second input FET having a gate connected to receive a second input signal, the first and the second input FETs being connected together to receive a first bias current, and also being connected to respective sides of a first current mirror. A correction amplifier circuit is also provided, that has a first correction FET having a gate, and a second correction FET having a gate, the first and the second correction FETs being connected together to receive a second bias current, and also being connected to respective sides of a second current mirror.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: September 19, 2006
    Assignee: Texas Instruments Incorporated
    Inventors: Amer Hani Atrash, Shanmuganand Chellamuthu
  • Patent number: 7098720
    Abstract: A thermal shutdown circuit board integrated circuit device. The thermal shutdown circuit includes a current source for receiving a current bias and generating an output current in accordance therewith. The current source is configured to produce the output current in a manner proportional to absolute temperature. A current mirror is coupled to the current source. The current mirror is configured to mirror the output current from the current source and is configured to have a high output impedance. A thermal shutdown transistor is coupled to control one output of the current mirror. The thermal shutdown transistor is also coupled to receive the output current and shutdown the output current at a temperature threshold in a manner dependent on shutdown circuit operating temperature.
    Type: Grant
    Filed: November 8, 2002
    Date of Patent: August 29, 2006
    Assignee: National Semiconductor Corporation
    Inventor: Ronald Neal Dow
  • Patent number: 7091713
    Abstract: A method and circuit are shown for generating a higher order compensated bandgap voltage is disclosed, in which a first order compensated bandgap voltage and a linearly temperature dependent voltage are generated. Thereafter, a difference between the linearly temperature dependent voltage and the first order compensated bandgap voltage is generated. The resulting difference voltage is squared, and finally the squared voltage is added to the first order compensated bandgap voltage, resulting in a higher order compensated bandgap voltage. There is also disclosed a higher order temperature compensated bandgap circuit.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: August 15, 2006
    Assignee: Integration Associates Inc.
    Inventors: János Erdélyi, András Vince Horváth
  • Patent number: 7088357
    Abstract: A power circuit supplies a plurality of voltages to a display-device-driving circuit for time-division-driving a display device. Each of the plurality of voltages are output via a constant-voltage circuit constituted by a regulator for dividing a voltage supplied from a power source and keeping the divided voltages at a certain voltage level, whereby a stable power source consuming a small amount of power when supplying power to a driving circuit as a power source for a display device to be time-division-driven can be obtained.
    Type: Grant
    Filed: June 21, 2005
    Date of Patent: August 8, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventor: Ritsuo Kashiyama
  • Patent number: 7075281
    Abstract: A current source for providing a current proportional to absolute temperature (a PTAT current) with high precision is implemented using only one off-chip component. The current source utilizes a bandgap voltage, a voltage related to a current proportional to absolute temperature and a constant current to bias a pair of voltage controlled resistive devices. In operation, a known resistance is derived by applying a constant voltage across and a constant current through a first voltage controlled resistive device. A control voltage for maintaining the constant current through the first voltage controlled resistive device is applied to control the second voltage controlled resistive device, thereby generating the highly precise PTAT current at the second voltage controlled resistive device. In one embodiment, the current source uses only one off-chip resistor in a constant current source for generating the constant current.
    Type: Grant
    Filed: August 15, 2005
    Date of Patent: July 11, 2006
    Assignee: Micrel, Inc.
    Inventor: Fred-Johan Pettersen
  • Patent number: 7071673
    Abstract: Several methods to obtain process insensitive base-emitter forward voltage of a transistor are described. The main concept is to recognize that the transistor current gain is the parameter that affects this voltage the most with normal process variations. The use of transistor driven with known base current removes this error. In alternative, a method for compensating the base-emitter forward voltage variations is described. This is applicable to analog integrated circuits that utilize the base-emitter forward voltage of a transistor and in particular in applications that make use of either accurate voltage references, thermal sensing elements, solid state thermostats and very common thermal shutdown protection circuits.
    Type: Grant
    Filed: August 4, 2004
    Date of Patent: July 4, 2006
    Assignee: ACU Technology Semiconductor Inc.
    Inventors: Paolo Menegoli, Carl K. Sawtell
  • Patent number: 7068024
    Abstract: Disclosed herein is a voltage regulator, and related method, for regulating a boost voltage generated by a boost circuit. In one embodiment, the voltage regulator includes a regulated voltage input operable to receive a regulated voltage derived from the boost voltage, a reference voltage input operable to receive a constant reference voltage, and an output node operable to provide a feedback signal to the boost circuit for controlling the generated boost voltage. In addition, the voltage regulator includes at least one transistor coupled to the regulated voltage input, the reference voltage input, and the output node, and operable to produce the feedback signal based on a comparison of the regulated voltage to the reference voltage.
    Type: Grant
    Filed: December 30, 2004
    Date of Patent: June 27, 2006
    Assignee: Taiwan Semiconductor Manufacturing Company, Ltd.
    Inventor: Chien-Hua Huang
  • Patent number: 6975314
    Abstract: There is provided a power circuit for a display-device-driving circuit for supplying a plurality of voltages to a driving circuit for time-division-driving a display device, wherein each of the plurality of voltages are output via a constant-voltage circuit constituted by a regulator for dividing a voltage supplied from a power source and keeping divided voltages at a certain voltage level, whereby a stable power source consuming a small power to a driving circuit as a power source for a display device to be time-division-driven can be obtained.
    Type: Grant
    Filed: January 30, 2003
    Date of Patent: December 13, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventor: Ritsuo Kashiyama
  • Patent number: 6958597
    Abstract: Voltage generating apparatus includes a positive temperature coefficient current generating module, a negative temperature coefficient current generating module, a fine-tune current module and a voltage output module. The function of the positive temperature coefficient current generating module and the negative temperature coefficient current generating module, which take advantage of characteristics of MOS devices operated in the sub-threshold region, is to generate a stable current of positive temperature coefficient and a stable current of negative temperature coefficient, respectively. The current fine-tune module increases or decreases output current of the negative temperature coefficient current generating module. The voltage output module sums two output currents of the positive temperature coefficient current generating module and the negative temperature coefficient current generating module and transforms the total current into output voltage that is stable under temperature and process variation.
    Type: Grant
    Filed: May 7, 2004
    Date of Patent: October 25, 2005
    Assignee: eMemory Technology Inc.
    Inventors: Hong-chin Lin, Po-Hsuan Huang, Chien-Hung Ho
  • Patent number: 6956397
    Abstract: The present invention provides a refresh clock generator which optimally controls a period of a refresh clock signal according to temperature variation and outputs the refresh clock signal. The refresh clock generator includes a bias voltage generating unit for generating first and second bias voltages in response to a temperature variation and a clock generator for generating a refresh clock signal having a frequency which is controlled or adjusted based on the first and second bias voltages, wherein the first bias voltage is varied in proportion to the temperature variation; the second bias voltage is varied in inverse proportion to the temperature variation; and the frequency of the refresh clock signal is varied in proportion to the temperature variation.
    Type: Grant
    Filed: December 1, 2003
    Date of Patent: October 18, 2005
    Assignee: Coremagic Inc.
    Inventors: Jung-Don Lim, Mi-Kyeong Yun
  • Patent number: 6937001
    Abstract: A circuit for generating a reference voltage includes a bandgap reference circuit that exhibits low temperature dependency of the output reference voltage. Since temperature dependencies of resistances thereof are appropriately controlled so that the temperature dependency of a load current flowing through divisional resistances is eliminated, it is possible to prevent the linearity of temperature dependency of the forward direction voltages of diodes from degrading. Accordingly, the temperature dependency of output is reduced.
    Type: Grant
    Filed: February 26, 2003
    Date of Patent: August 30, 2005
    Assignee: Ricoh Company, Ltd.
    Inventor: Yoshinori Ueda
  • Patent number: 6922045
    Abstract: Disclosed is current driver circuit comprising a bandgap reference circuit for generating a fixed current and a current proportional to absolute temperature (PTAT), a temperature compensator for combining the fixed and PTAT currents and forming first and second temperature compensated currents, a current control circuit for modifying said first and second temperature compensated currents in response to signals representing the characteristics of a load device and a driver circuit for amplifying and supplying a selected one of said first and second temperature compensated currents to said load device. Also disclosed is a method of supplying a precisely controlled current by generating a constant current and a current proportional to absolute temperature (PTAT), combining these two currents and providing temperature compensated currents, modifying the temperature compensated currents with a programmed reference signal and supplying a precisely controlled current to a load device.
    Type: Grant
    Filed: February 13, 2003
    Date of Patent: July 26, 2005
    Assignee: Primarion, Inc.
    Inventors: David W. Self, C. Phillip McClay
  • Patent number: 6906902
    Abstract: A semiconductor integrated circuit comprises a transistor which has a first electrode, a second electrode and a third electrode, said transistor conducting a current of a first power source from the second electrode to the third electrode by a power supplied to the first electrode; a driver to supply said first electrode with power for driving said transistor; a reference voltage circuit to generate a reference voltage which is variable in response to temperature of said transistor, said reference voltage being used as the reference for comparison; a comparative voltage circuit to generate a comparative voltage which is variable in response to a current flowing from said second electrode to said third electrode, said comparative voltage being compared with said reference voltage; and a controller which receives said reference voltage and said comparative voltage and which supplies a control signal to said driver, said control signal being based on a result of the comparison between the comparative voltage and
    Type: Grant
    Filed: October 4, 2002
    Date of Patent: June 14, 2005
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Kiyomi Watanabe
  • Patent number: RE40673
    Abstract: Each of stages RS(1), RS(2), . . . of a shift register is constituted by six TFTs. A ratio of a channel width and a channel length (W/L) of each of these TFTs 1 to 6 is set in accordance with a transistor characteristic of each TFT in such a manner that the shift register normally operates for a long time even at a high temperature.
    Type: Grant
    Filed: July 29, 2005
    Date of Patent: March 24, 2009
    Assignee: Casio Computer Co., Ltd.
    Inventors: Minoru Kanbara, Kazuhiro Sasaki, Katsuhiko Morosawa
  • Patent number: RE40915
    Abstract: A current-sensing and correction circuit having programmable temperature compensation circuitry that is incorporated into a pulse width modulation controller of a buck mode DC—DC converter. The front end of the controller contains a sense amplifier, having an input coupled via a current feedback resistor to a common output node of the converter. The impedance of a MOSFET, the current through which is sampled by a sample and hold circuit is controlled by the sense amplifier unit. A sensed current correction circuit is coupled between the sample and hold circuit and the controller, and is operative to supply to the controller a correction current having a deterministic temperature-compensating relationship to the sensed current. The ratio of correction current to sensed current equals to value of one at a predetermined temperature, and has other values at temperatures other than at that temperature.
    Type: Grant
    Filed: July 18, 2006
    Date of Patent: September 15, 2009
    Assignee: Intersil Americas Inc.
    Inventor: Robert Haynes Isham