Zener Patents (Class 323/231)
  • Patent number: 10120405
    Abstract: A single semiconductor-based junction may be used to create a voltage reference, and temperature compensate the voltage reference, by time-multiplexing the voltage reference between different current drive levels. That is, the value of the current driven through the single junction may be repeatedly varied in a recurring manner. In case the junction is a zener diode, the current may be repeatedly switched between forward and reverse directions. As long as the temperature coefficients (in ppm/° C.) of the different voltages developed responsive to the different currents across the junction are different, a weighting of the different voltage values yield a zero temperature coefficient voltage reference value. To implement a bandgap reference, a single diode-connected bipolar junction transistor may alternately be forward-biased using a first current and at least a second current.
    Type: Grant
    Filed: April 4, 2014
    Date of Patent: November 6, 2018
    Inventor: Christopher G. Regier
  • Patent number: 9722408
    Abstract: An apparatus includes an energy storage module that receives power from an AC power source. The energy storage module is sized to store electrical energy received from the AC power source that is sufficient to open one or more contacts when the AC power source is not present. The contacts disconnect electrical power to a load and the electrical energy is stored in a DC energy storage device. A connection module connects the energy storage device in series with a trip contact, a trip circuit, and an auxiliary contact. The trip contact closes in response to a trip signal. The trip circuit disconnects the one or more contacts in response to being energized, and the auxiliary contact opens in response to opening of the one or more contacts and disconnects power to the trip circuit. A disconnect module periodically disconnects electrical power from the trip circuit and the auxiliary contact.
    Type: Grant
    Filed: March 13, 2015
    Date of Patent: August 1, 2017
    Inventor: Dale Curtis
  • Patent number: 9673726
    Abstract: A capacitive power supply device for a control device of an electrical switching apparatus, including a power supply module that has two input terminals and a power supply voltage between the two terminals, and suitable for supplying a power supply current to a control member suitable for controlling the electrical switching apparatus when the power supply voltage is below a predetermined actuation threshold, the power supply module including a first capacitor connected at the input of voltage rectifying means, the control member being connected at the output of a rectifying block, wherein a second capacitor and a first switch, suitable for connecting the second capacitor based on a comparison of the power supply voltage to a capacitor switching threshold value.
    Type: Grant
    Filed: November 27, 2015
    Date of Patent: June 6, 2017
    Inventors: Francois Vincent, Bruno Bordet
  • Patent number: 9575471
    Abstract: A field device for process instrumentation comprises a measuring and comparison device and a readable storage element. The measuring and comparison device is configured for monitoring an operating characteristic variable for compliance with a predefined range. The readable storage element maintains a state. The storage element state is permanently changed if a value held by the operating characteristic variable goes out of said predefined range. The predefined range is determined in such a manner that, as a result of a changed state of the storage element, a loss of suitability of the field device for special operation with an operating characteristic variable with restricted specifications, but not a loss of suitability for normal operation with an operating characteristic variable with less restricted specifications, is indicated.
    Type: Grant
    Filed: July 25, 2014
    Date of Patent: February 21, 2017
    Assignee: Siemens Aktiengesellschaft
    Inventor: Michael Geppert
  • Patent number: 9372494
    Abstract: The present application describes a current regulator for providing a regulated current from an input voltage. The current regulator comprises a voltage regulator circuit, operable to provide a regulated voltage, which comprises a plurality of Zener diodes connected in parallel.
    Type: Grant
    Filed: June 22, 2012
    Date of Patent: June 21, 2016
    Assignee: ACCURIC LTD.
    Inventor: Dave Bannister
  • Patent number: 8947056
    Abstract: A switching transistor is arranged between a switching (SW) terminal and the ground terminal. An error amplifier amplifies the difference between the feedback voltage VFB that corresponds to the output voltage VOUT with a predetermined reference voltage VREF so as to generate an error voltage VERR. A pulse modulator generates a pulse signal SP having a duty ratio that is adjusted according to the error voltage VERR. A driver drives a switching transistor according to the pulse signal SP. An overvoltage detection circuit generates an overvoltage protection (OVP) signal which is asserted when the voltage at the switching (SW) terminal becomes higher than a predetermined threshold voltage. When the OVP signal is asserted, a control circuit performs a predetermined protection operation.
    Type: Grant
    Filed: May 4, 2012
    Date of Patent: February 3, 2015
    Assignee: Rohm Co., Ltd.
    Inventors: Nobukazu Tsukiji, Kazuhiro Murakami
  • Patent number: 8730689
    Abstract: A capacitive power supply including an input section having input terminals for connection to an AC-mains supply, and a capacitive coupling, a rectification section coupled via the capacitive coupling to the input terminals, and an output section coupled to the rectification section, the output section including output terminals, for providing an output voltage to a load, a first chain including a charge storage facility, and a second chain arranged in parallel to the first chain, and including an output voltage limiting facility, the capacitive power supply further including an inrush current limiting facility, wherein the output terminals are connected to respective terminals of the output voltage limiting facility, and the DC-conducting series impedance has a resistive component with a resistive value of at least 0.2 times a resistive value of the first chain.
    Type: Grant
    Filed: November 21, 2008
    Date of Patent: May 20, 2014
    Assignee: Koninklijke Philips N.V
    Inventor: Thijs De Haan
  • Patent number: 8552680
    Abstract: An electronic device includes a first rechargeable battery, a solar cell mounted on the electronic device, a second rechargeable battery and a power management circuit. The power management circuit includes a control module, a DC/DC module, a switch and a power supply switching module. The DC/DC module is configured for converting the DC power generated by the solar cell from one voltage level to another, and activating and maintaining the activation of the control module. The switch is turned on by the control module when the control module is activated, causing the DC power from the DC/DC module to charge the second rechargeable battery. The power supply switching module is controlled by the control module to select the second rechargeable battery to power the electronic device if the voltage level of the rechargeable battery is lower than that of the second rechargeable battery.
    Type: Grant
    Filed: August 31, 2010
    Date of Patent: October 8, 2013
    Assignees: Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd., Hon Hai Precision Industry Co., Ltd.
    Inventors: Xin Zhao, Hua-Dong Cheng, Ruey-Shyang You, Han-Che Wang, Xiao-Guang Li, Kuan-Hong Hsieh
  • Publication number: 20130221755
    Abstract: A circuit arrangement for setting a potential of a photovoltaic generator with respect to a ground potential (GND) includes at least one first resistance connected between a negative output of the photovoltaic generator and a ground connection, and a series circuit including at least one second resistance and a breakdown diode connected in series between a positive output of the photovoltaic generator and the ground connection to which the ground potential (GND) is applied. Alternatively, the circuit arrangement includes at least one first resistance connected between a positive output of the photovoltaic generator and a ground connection, and a series circuit including at least one second resistance and a breakdown diode connected in series between a negative output of the photovoltaic generator and the ground connection to which the ground potential (GND) is applied.
    Type: Application
    Filed: April 11, 2013
    Publication date: August 29, 2013
    Applicant: SMA Solar Technology AG
    Inventor: SMA Solar Technology AG
  • Patent number: 8450993
    Abstract: The present invention relates to a conventional circuit connected with the direct-current (DC) power supply in series through the semiconductor forward voltage drop, for producing voltage drop to lower the output DC voltage, however, if the output current is smaller, the voltage drop produced is not enough, the floating-voltage accordingly rises and damages the load, so a shunting current load is arranged in the circuit to suppress the floating-voltage.
    Type: Grant
    Filed: March 15, 2010
    Date of Patent: May 28, 2013
    Inventor: Tai-Her Yang
  • Patent number: 8193785
    Abstract: A switching regulator for regulating an ac signal, and method of supplying power thereto wherein the regulator includes a positive half cycle part and a negative half-cycle part arranged to regulate the respective parts of an input ac signal. Each half-cycle part includes a modulating transistor, having an associated modulator diode, and a clamping diode arranged to protect the modulating transistor from reverse-bias voltages and having an associated clamp switch. The regulator further has a first switching controller operable to cause the modulating transistors to switch and a second, separate switching controller operable to cause the clamp switches to switch.
    Type: Grant
    Filed: December 28, 2006
    Date of Patent: June 5, 2012
    Assignee: Microgen Engine Corporation Holding B.V.
    Inventor: Raymond John Peto
  • Patent number: 8053997
    Abstract: A two-wire load control device, such as a dimmer, is operable to control the amount of power delivered to an electrical load, such as a magnetic low-voltage (MLV) load, and comprises a bidirectional semiconductor switch, a timing circuit, a trigger circuit having a variable voltage threshold, and a clamp circuit. When a timing voltage signal of the timing circuit exceeds an initial magnitude of the variable voltage threshold, the trigger circuit is operable to render the semiconductor switch conductive, reduce the timing voltage signal to a predetermined magnitude less than the initial magnitude, and to increase the variable voltage threshold to a second magnitude greater than the first magnitude. The clamp circuit limits the magnitude of the timing voltage signal to a clamp magnitude between the initial magnitude and the second magnitude, thereby preventing the timing voltage signal from exceeding the second magnitude.
    Type: Grant
    Filed: May 8, 2009
    Date of Patent: November 8, 2011
    Assignee: Lutron Electronics Co., Inc.
    Inventor: Christopher James Salvestrini
  • Patent number: 8004233
    Abstract: The solar powered direct current (DC) load system is a reliable, versatile and user friendly system; it uses solar energy and rechargeable battery powering at least one type of DC load which are: a type of motor operation such as water pump and/or a type of at least one LED; the system comprises a battery discharge control circuit and a battery output circuit for DC load (FIG. 1), at least one rechargeable battery source (42-F1) which is protected by a preset voltage that limits the lowest discharge level, the circuits in the FIG. 1 are able to combine the circuits in FIG. 2 and FIG. 3 which enable operations of the day time and night time DC load to synchronize the day and night cycles; FIG. 4 is a combination system which incorporates circuits in the FIG. 1 and FIG. 2 to create a water pumping system combined an illumination system which can turn on and off automatically; FIG. 4a with a switch and additional LEDs in addition to the FIG. 4; FIG.
    Type: Grant
    Filed: October 11, 2010
    Date of Patent: August 23, 2011
    Inventor: Min Carroll
  • Patent number: 7847512
    Abstract: The solar powered direct current (DC) load system is a reliable, versatile and user friendly system; it uses solar energy and rechargeable battery powering at least one type of DC load which are: a type of motor operation such as water pump and a type of at least one LED; the system comprises a battery discharge control circuit and a battery output circuit for DC load (FIG. 1), at least one rechargeable battery source (42-F1) which is protected by a preset voltage that limits the lowest discharge level, the circuits in the FIG. 1 are able to combine the circuits in FIG. 2 and FIG. 3 which enable operations of the day time and night time DC load to synchronize the day and night cycles; FIG. 4 is a combination system which incorporates circuits in the FIG. 1 and FIG. 2 to create a water pumping system combined an illumination system which can turn on and off automatically; FIG. 4a with a switch and additional LEDs in addition to the FIG. 4; FIG. 5 is a combination system that incorporates circuits in the FIG.
    Type: Grant
    Filed: March 17, 2009
    Date of Patent: December 7, 2010
    Inventor: Min Carroll
  • Patent number: 7834607
    Abstract: A voltage generator with current limiting generates a voltage to be fed to a load of which load current is limited. The voltage generator includes an operational amplifier; an output resistance connected between an output terminal of the operational amplifier and a load connecting terminal; a feedback resistor connected between the load connecting terminal and an inverting input terminal of the operational amplifier; a first clamper connected between the output terminal of the operational amplifier and the inverting input terminal of the operational amplifier; and a second clamper connected between the load connecting terminal and a non-inverting input terminal of the operational amplifier and configured with diodes. The first clamper generates a predetermined constant voltage, limits a current flowing into the output resistance, and varies the generated constant voltage. The first clamper has a predetermined abrupt current-voltage characteristic.
    Type: Grant
    Filed: January 26, 2007
    Date of Patent: November 16, 2010
    Assignee: Advantest Corporation
    Inventor: Shoji Kojima
  • Patent number: 7602158
    Abstract: A power circuit generating a non-isolating low voltage power supply using a capacitive AC voltage drop in standby. Specifically, the power circuit includes an AC connector that generates a first AC input and a second AC input that are opposite in phase. The power circuit also includes first and second diode bridge rectifier circuits that are coupled to the first AC input, the second AC input, and a ground. A first capacitor drops a voltage of the first AC input, and a second capacitor drops a voltage of the second AC input. The first diode bridge rectifier circuit provides a high voltage power signal to a load. The second diode bridge rectifier circuit provides a low voltage power signal to a microcontroller.
    Type: Grant
    Filed: March 21, 2005
    Date of Patent: October 13, 2009
    Assignee: National Semiconductor Corporation
    Inventor: Alin Theodor Iacob
  • Patent number: 7579813
    Abstract: A power regulator with a constant-voltage output is provided, which includes a voltage regulator module and a voltage buffer module, wherein the voltage regulator module is spaced from a load by the voltage buffer module, so that an output voltage of the voltage regulator module is not affected by the current of the load, thereby enhancing the output precision of the power regulator.
    Type: Grant
    Filed: January 29, 2007
    Date of Patent: August 25, 2009
    Assignee: Inventec Corporation
    Inventor: Cheng-Shun Fan
  • Publication number: 20080143309
    Abstract: A power supply converter is disclosed. An apparatus according to aspects of the present invention includes a power supply converter having an energy transfer element coupled between a power converter input and first and second power converter outputs. A switch is coupled between the power converter input and the energy transfer element. A control circuit is coupled to the switch to control switching of the switch to generate a first output voltage at the first power converter output and a second output voltage at the second power converter output. A sum of the first and the second output voltages is regulated in response to a first voltage reference. The second output voltage is regulated in response to a second voltage reference. A current in the energy transfer element is coupled to be increased when a voltage across the energy transfer element is a difference between an input voltage at the power converter input and the first output voltage.
    Type: Application
    Filed: December 18, 2006
    Publication date: June 19, 2008
    Inventors: Arthur B. Odell, Tiziano Pastore, Matteo Uccelli
  • Patent number: 7245511
    Abstract: A power supply system and corresponding methodology is provided for providing a self-protected power supply for use with electronic electricity meters. The self-protecting features are provided, in part, through the use of surface mounted resistive components corresponding to a resistor dropper portion of the power supply. The use of surface mount components also provides a general reduction in circuit board surface area requirements thereby providing a compact overall construction and provides economies with respect to reduction in manufacturing process steps. When the surface mount resistor divider is configured along with a half-wave rectifier, a low voltage DC supply is obtained from a direct connection to a much higher voltage AC mains source without requiring the use of coupling capacitors or transformers. Plural output voltages may be provided and capacitive filtering may be associated with the outputs.
    Type: Grant
    Filed: August 23, 2005
    Date of Patent: July 17, 2007
    Assignee: Itron, Inc.
    Inventors: Andrew Lancaster, Philippe Chiummiento, Sudhir Thumaty
  • Patent number: 6275013
    Abstract: A switching power supply includes a rectifying and smoothing circuit 6 coupled to an inductor L1 and a zener diode D2 coupled to the output of the rectifying and smoothing circuit 6. An internal resistor on the inductor L1 side viewed through the rectifying and smoothing circuit 6 is employed as a serial resistor for generating the voltage drop which is required for the zener diode D2 to absorb voltage fluctuation, whereby the voltage of the DC output 22 is stabilized.
    Type: Grant
    Filed: July 21, 2000
    Date of Patent: August 14, 2001
    Assignee: Funai Electric Co., Ltd.
    Inventor: Yoshio Higuchi
  • Patent number: 6222350
    Abstract: A high voltage shunt regulator circuit includes a high voltage device with a predetermined reverse-conduction threshold connected in series with a thermal compensation device comprising a plurality of gate threshold amplifiers connected in series with one another. The high voltage device includes a plurality of zener diodes connected in series. Each of the gate threshold amplifiers includes a resistive voltage divider and a voltage-controlled resistive device, preferably a MOSFET. The voltage divider is formed by first and second resistors connected in series between first and second terminals of the gate threshold amplifier, with a MOSFET having its drain connected to the first terminal, its source connected to the second terminal, and its gate connected to an intermediate tap of the voltage divider.
    Type: Grant
    Filed: January 21, 2000
    Date of Patent: April 24, 2001
    Assignee: Titan Specialties, Ltd.
    Inventor: Demmie L. Mosley
  • Patent number: 6061577
    Abstract: An electricity power supply circuit for an external appliance whose consumption varies over time. The circuit comprises an electrochemical cell, a supercapacitor serving as a source of electricity for said appliance, and a chopper voltage converter between the cell and the supercapacitor, the converter serving to charge the supercapacitor at constant current while monitoring the voltage across the terminals thereof. The circuit is applicable to cellular radiotelephones.
    Type: Grant
    Filed: December 19, 1995
    Date of Patent: May 9, 2000
    Assignee: Alcatel
    Inventors: Xavier Andrieu, Philippe Poignant
  • Patent number: 5701071
    Abstract: Systems for controlling the current consumption of an integrated circuit chip and the like so as to reduce the inductive voltage drops occurring over the power supply lines within the chip and power supply lines to the chip are disclosed. The systems according to the present invention are applicable to circuits having two or more sub-circuits formed on a semiconductor substrate, each sub-circuit having two or more power supply inputs. An exemplary system comprises two or more current shunting elements formed on the substrate, with each current shunting element coupled in parallel with the power supply inputs of a selected sub-circuit. The system has at least two main power supply lines formed on the semiconductor substrate, with each selected sub-circuit having each of its power supply inputs coupled to a main power supply line. A current shunting element may comprise a Zener diode, an active shunt circuit, or equivalents thereof.
    Type: Grant
    Filed: August 21, 1995
    Date of Patent: December 23, 1997
    Assignee: Fujitsu Limited
    Inventors: Jiunn-Yau Liou, Richard L. Wheeler, Bidyut Sen, James C. Parker, Jr.
  • Patent number: 5568043
    Abstract: A dual voltage generation circuit, responsive to a switching signal, to selectively generates a constant voltage at an output terminal is provided. The generation circuit comprises a switch transistor, a first and a second zener diodes and a diode. As the switching signal is logic high, at the output terminal, the circuit outputs a first constant voltage, and as the switching signal is logic low, the circuit outputs a second constant voltage.
    Type: Grant
    Filed: August 1, 1995
    Date of Patent: October 22, 1996
    Assignee: Acer Peripherals, Inc.
    Inventor: Ming-Jer Wu
  • Patent number: 5457623
    Abstract: A high power, high efficiency power converter for illumination loads, with low heat dissipation. In the preferred embodiment, the converter utilizes a switching means pair providing a high frequency inverter, provided by a pair of FETs, each arranged in one of a pair of gate driver loops connected to the auxiliary windings of a transformer whose primary winding samples the current through an illumination load. The periodic turn-off and turn-on operation of each of the FET switches is defined as the switching frequency, which is dependent on a Zener diode connected across the FET gate in each of the respective driver loops. The Zener breakdown voltage determines the winding voltage and transformer saturation point, at which time one FET switches off, and the other turns on. Use of FETs as the switching device provides several advantages, including a quicker switching time and reduced switching losses and power dissipation.
    Type: Grant
    Filed: July 6, 1993
    Date of Patent: October 10, 1995
    Assignee: Shafrir Romano
    Inventor: Dror Manor
  • Patent number: 5304861
    Abstract: A detection circuit that does not vary with the supply voltage is formed by measuring the voltage generated at the terminals of a diode (1) which is reverse biased and is supplied by a constant current generator (2). Furthermore, the generator (2) is improved by a current consumption limitation circuit (5). This circuit is particularly designed to be implanted in CMOS technology on the same substrate as a memory circuit or a microprocessor circuit.
    Type: Grant
    Filed: May 5, 1992
    Date of Patent: April 19, 1994
    Assignee: SGS-Thomson Microelectronics S.A.
    Inventors: Serge Fruhauf, Michel Martin
  • Patent number: 5291365
    Abstract: First, second, and third power supply lines are separate from each other. A power supply circuit receives electric power from the first power supply line, and generates a given power supply voltage from the received electric power and outputs the generated power supply voltage to the third power supply line. An electronic circuit is connected to the third power supply line to be activated by the power supply voltage. The electronic circuit has an input section for receiving an input signal from the second power supply line. A protective circuit provided in the electronic circuit leaks a current from the input section of the electronic circuit toward the third power supply line when a voltage of the input signal exceeds the power supply voltage.
    Type: Grant
    Filed: October 22, 1992
    Date of Patent: March 1, 1994
    Assignee: Nippondenso Co., Ltd.
    Inventor: Nobutomo Takagi
  • Patent number: 5252908
    Abstract: An auto-TC voltage reference wherein an operational amplifier receives at one input the voltage of a Zener diode and at its other input receives a compensation signal from a feedback circuit comprising a transistor and resistor network. When one of the resistors of the network is trimmed to give a nominal output voltage for the reference, the TC of the reference voltage will have been reduced to zero, or nearly so. The circuitry is capable of compensating Zener diodes of either positive or negative TC.
    Type: Grant
    Filed: December 9, 1992
    Date of Patent: October 12, 1993
    Assignee: Analog Devices, Incorporated
    Inventor: Adrian P. Brokaw
  • Patent number: 5227963
    Abstract: A three-phase flat-top waveform generator which may be utilized in a pulse-width modulator. Transfer function means receive a three-phase input signal and produce therefrom a zero sequence signal. Under steady-state and balanced conditions, the zero sequence signal will generally have a fundamental frequency three times the frequency of the input signal. Summing means add the zero sequence signal to each phase of the input signal to produce the desired flat-top signal.
    Type: Grant
    Filed: April 16, 1992
    Date of Patent: July 13, 1993
    Assignee: Westinghouse Electric Corp.
    Inventor: Colin D. Schauder
  • Patent number: 5027165
    Abstract: An improved zener diode formed in a semiconductor wafer having a primary surface, the zener diode having a PN junction buried beneath the surface. The diode includes a pair of spaced contacts on the surface, the first located on one region and the second located on another laterally spaced region of the surface, to establish a current path through the diode. A replica device is formed on the same wafer generally replicating the physical dimensions of the zener diode. The replica device has a pair of spaced surface contacts located on spaced regions of the surface with a replica current path between them having substantially the same resistance as the on-resistance of the current path of the diode, the replica current path replicating the current path except that it has no PN junction.
    Type: Grant
    Filed: May 22, 1990
    Date of Patent: June 25, 1991
    Assignee: Maxim Integrated Products
    Inventor: Tunc Doluca
  • Patent number: 4994731
    Abstract: A device for sensing the speed of a rotating element in a vehicle replaces the practice of using magnetic wire coil pickup devices placed in close proximity to a rotating element, such as a gear. The main speed sensing component is a conventional three lead Hall effect device which produces a voltage each time it is exposed to the presence of a magnetic force which exceeds a predetermined value. The adoption of a device which produces the Hall effect introduces the complication of harmonizing the connection of the three leads of the standard Hall effect device with the connections conventionally found in existing installation of only two leads between the sensing unit and the controlled element. Transistor diode and resistive components mounted in the same housing as the Hall effect device provide a configuration entirely compatible with existing two lead systems.
    Type: Grant
    Filed: November 27, 1989
    Date of Patent: February 19, 1991
    Assignee: Navistar International Transportation Corp.
    Inventor: John A. Sanner
  • Patent number: 4982316
    Abstract: A polyphase full-wave rectifying circuit that is connected to a polyphase AC line having a neutral point includes DC output terminals and plural pairs of rectifying elements. Each pair is composed of two rectifying elements in series and these pairs are connected in parallel with each other between the DC output terminals. One of the pairs of rectifying elements is a pair of Zener type rectifying elements and the interconnection point of this pair is to the neutral point of the polyphase AC line. The other pairs are pairs of ordinary type rectifying elements, each interconnection point of these pairs is to each phase point of the polyphase AC line. Both internal surges and external surges are absorbed through the pair of Zener type elements. Therefore, the clamping voltages of the internal and external surges results in the same level, being twice as high as the Zener voltage. The peak voltage applied to one Zener type element reduces by half the surge peak voltage.
    Type: Grant
    Filed: November 9, 1989
    Date of Patent: January 1, 1991
    Assignee: Kabushiki Kaisha Toshiba
    Inventor: Hirofumi Nakayama
  • Patent number: 4982318
    Abstract: A DC power supply which is adapted to produce a DC main voltage between a main output terminal provided at one end of a first line and a ground terminal provided at one end of a second line; the power supply being characterized in that there is disposed a constant-voltage-drop means between the second line and the ground terminal; a third line extends from the second line side of the constant voltage drop means; and also an inverse polarity side output terminal is disposed at one end thereof so that an inverse polarity DC side voltage is adapted to be outputted between the inverse polarity side output terminal and the ground terminal, whereby main and side output voltage having opposite polarities can be produced through a simple construction.
    Type: Grant
    Filed: April 4, 1990
    Date of Patent: January 1, 1991
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Yukio Maeba, Takahito Chinomi
  • Patent number: 4868907
    Abstract: An electrophotographic system including a corona charging device for applying a charge to a surface and having a coronode driven to a corona producing condition; a conductive grid interposed between the surface to be charged and the coronode; the conductive grid having a self-biasing arrangement to control the voltage thereon produced by corona current from the coronode, the self-biasing arrangement including a current sinking device between the conductive grid and a common; and a power supplying takeoff, electrically connected between the conductive grid and the current sinking device, and having a voltage thereat controlled by the current sinking device.
    Type: Grant
    Filed: May 18, 1988
    Date of Patent: September 19, 1989
    Assignee: Zerox Corporation
    Inventor: Jeffrey J. Folkins
  • Patent number: 4794277
    Abstract: A low voltage lockout circuit preferably of integrated circuit form to provide a lockout signal when an internally generated reference voltage is insufficient. According to the present invention, a reference voltage is produced by passing a constant current through a reference voltage element, such as a zener diode. Insufficient reference voltage caused by a low power supply input voltage is detected by sensing the saturation of the constant current source. The present invention indicates the precise point of saturation of the constant current source and produces a lockout signal for use by other portions of the integrated circuit, or external devices. The lockout signal also indicates the minimum usable power supply input voltage. The constant current source and the saturation detection element are combined and implemented within a single semiconductor structure.
    Type: Grant
    Filed: August 10, 1987
    Date of Patent: December 27, 1988
    Assignee: Unitrode Corporation
    Inventor: Varnum S. Holland
  • Patent number: 4774452
    Abstract: A zener diode is connected at one end via a first impedance to a first power terminal. The base-to-emitter junctions of first and second transistors are connected in parallel between the other end of the zener diode and a second power terminal. The collector of the first transistor is connected to the one end of the zener diode to regulate the zener current and hence the zener voltage. A third transistor is coupled at its base to the one end of the zener and its emitter is connected to an output terminal to produce an output voltage which is a function of the zener voltage. The collector of the second transistor is connected to the emitter of the third transistor to pass a current through the third transistor which is approximately equal to the current through the first and second transistors whereby the base-to emitter junction of the third transistor and its temperature variations have little, if any, effect on the output voltage.
    Type: Grant
    Filed: May 29, 1987
    Date of Patent: September 27, 1988
    Assignee: GE Company
    Inventor: Syed M. Ahmed
  • Patent number: 4764716
    Abstract: A stabilizing circuit for the operating voltage of a microcomputer, in which the input of the circuit is connected to a power supply, and the output of the circuit is connected to the operating voltage-input of the microcomputer.
    Type: Grant
    Filed: March 19, 1987
    Date of Patent: August 16, 1988
    Assignee: Diehl GmbH & Co.
    Inventor: Wilhelm Sturzl
  • Patent number: 4748533
    Abstract: An integrated circuit for protecting subscriber lines against overvoltages includes a semiconductor body; a field-controllable thyristor having a gate electrode, an anode electrode and a cathode electrode, the gate electrode being insulated from the semiconductor body; a resistor connected between the cathode electrode and the gate electrode; a series circuit of Zener diodes connected between the gate electrode and the anode electrode, each of the Zener diodes having an anode electrode and a cathode electrode; and short circuit jumpers each being connected between the anode electrode and the cathode electrode of a respective one of at least part of the Zener diodes; at least part of the jumpers being interrupted corresponding to a predetermined breakdown voltage of the series circuit; and the thyristor having a larger breakdown voltage than the combined breakdown voltages of the Zener diodes of the series circuit of Zener diodes.
    Type: Grant
    Filed: November 4, 1986
    Date of Patent: May 31, 1988
    Assignee: Siemens Aktiengesellschaft
    Inventors: Helmut Hertrich, Fritz Kirschner, Jeno Tihanyi
  • Patent number: 4701835
    Abstract: A flashlight which can be operated directly either by a rechargeable batt or by a hand-cranked alternator. The alternator can also simultaneously operate the light and recharge the battery, or only recharge the battery. The alternator is integrally attached to a harmonic drive system which allows the alternator rotor to be driven at high speeds.
    Type: Grant
    Filed: September 19, 1985
    Date of Patent: October 20, 1987
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Carl J. Campagnuolo, Asaf A. Benderly
  • Patent number: 4695784
    Abstract: A battery charging circuit includes a silicon controlled rectifier full wave bridge that has its input connected across a conventional 60 hertz alternating current power line. The output of the bridge provides 120 hertz pulsating direct current to the battery being charged. The duration of each direct current charging pulse is determined by phase triggering of the silicon controlled rectifiers in the bridge. The silicon controlled rectifiers are triggered at a predetermined, identical firing angles by a conventional unijunction transistor relaxation oscillator which in turn is regulated by an output voltage and output current sensing circuit that established the noted firing angles so as to regulate, and limit at desirable upper valves, the charging voltage and current applied to the battery.
    Type: Grant
    Filed: September 4, 1986
    Date of Patent: September 22, 1987
    Inventor: William R. Reynolds
  • Patent number: 4686449
    Abstract: A JFET current source compensates for variations in the voltage supply to intain a constant current level at its output terminal. Series connected diodes are used as voltage dividers in conjunction with a second JFET to establish the gate voltage of a third JFET that is connected in series with the first JFET. The constant current output is taken at the drain electrode of the third JFET.
    Type: Grant
    Filed: April 7, 1986
    Date of Patent: August 11, 1987
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Edward N. Jeffrey, Chi-Cheong Shen
  • Patent number: 4668903
    Abstract: A voltage reference supply circuit is described that provides temperature compensation over a wide range of temperatures. The circuit includes a plurality of thermistor temperature dependent elements and these thermistor elements are utilized to compensate for the variation in the reference potential voltage of the Zener diode. The compensation is provided by determining the output voltage as a function of the circuit parameters and by varying pre-established resistive values in known ranges until the variations in the output voltage with temperature have been reduced below a predetermined value over the entire prescribed temperature range. Using this procedure, a variation in output voltage over the temperature range of -55.degree. C. to +125.degree. C. can be held within 50 parts per million.
    Type: Grant
    Filed: August 15, 1985
    Date of Patent: May 26, 1987
    Assignee: Thaler Corporation
    Inventor: Hubert F. Elbert
  • Patent number: 4665355
    Abstract: A solid state power controller off-line capacitor divider power supply coupler between an ac voltage source output terminal and neutral terminal, supplying regulated dc voltage levels referenced to the ac voltage source output terminal to a load such as the control and drive circuits of a solid state power controller. The invention circuit comprises an input capacitor having a first and second terminal. The capacitor first terminal is coupled to the ac voltage source neutral terminal. A first diode has an anode and a cathode; the anode is coupled to the capacitor second terminal. A positive filter capacitor has a first and second terminal. The first terminal being coupled to the first diode cathode and the filter capacitor second terminal being coupled to the control and drive circuit reference terminal. The invention circuit has a first positive regulator means with an input terminal, an output terminal and a reference terminal. The input terminal is coupled to the filter capacitor first terminal.
    Type: Grant
    Filed: September 15, 1986
    Date of Patent: May 12, 1987
    Assignee: Rockwell International Corporation
    Inventors: Patrick E. McCollum, Mark E. Colan
  • Patent number: 4657347
    Abstract: A liquid crystal display apparatus includes a liquid crystal display device having a plurality of display digits, a one-chip microcomputer having a plurality of voltage terminals for driving the liquid crystal display device by selectively supplying the voltages applied to those voltage terminals to the liquid crystal display device, and a power supply circuit for applying voltages to the voltage terminals, this power supply circuit having a series circuit of a plurality of resistors one end of which is connected to the first power source terminal and which has a plurality of nodes connected to the voltage terminals. The power supply circuit has a Zener diode which is connected between the other end of the series circuit and the second power source terminal and which is made operative in the saturation region.
    Type: Grant
    Filed: August 12, 1986
    Date of Patent: April 14, 1987
    Assignee: Tokyo Electric Co., Ltd.
    Inventor: Yoshiharu Nishimura
  • Patent number: 4639551
    Abstract: The invention relates to power supply circuits, and in particular those used for directly supplying, from a telephone line, the bell or other items in a telephone set. In order to avoid unacceptable crosstalk or distortion due to saturation of the power supply circuit when the AC signal on the line drops below the value (Vs) of the regulated output voltage of the power supply, there is provision for detection of this saturation (56) and current shunting (T2, T3) that increases progressively with saturation, such that, seen from the line, the current consumption or impedance of the set remains constant despite the disturbances due to saturation.
    Type: Grant
    Filed: July 12, 1984
    Date of Patent: January 27, 1987
    Assignee: Thomson-CSF
    Inventor: Jean C. Kaire
  • Patent number: 4609863
    Abstract: This power supply device comprises a voltage regulating element, a constant-current source, first and second constant-current circuits, and a current switching circuit interposed between the first and second constant-current circuits and the constant-current source, and by comparing an input voltage with an output voltage to introduce constant current from the first constant-current circuit to the voltage regulating element when the input voltage is higher than the output voltage, while introducing the constant current from the second constant-current circuit to ground terminal when the input voltage is lower than the output voltage. Thus, a stabilized DC voltage may be produced from a DC voltage including a superposed AC signal without interfering with the AC communications signal.
    Type: Grant
    Filed: October 18, 1984
    Date of Patent: September 2, 1986
    Assignees: Iwatsu Electric Co., Ltd., Rohm Company Limited
    Inventors: Kachio Asai, Yuji Tsuruga
  • Patent number: 4608529
    Abstract: A constant voltage circuit has two rails 10 and 12, with one rail 12 at a variable potential V, possibly supplied by a voltaic cell. In one arm between the rails there is voltage reference means Z1, 14, with a circuit output line 16 connected thereto, and the line 16 is required to be maintained at a potential V.sub.o, corresponding to a maximum value for V. In a second arm there is provided a first resistor R1, connected to the rail 12, and in series with a transistor T2. A second, equal, resistor R2 is connected between the output line 16 and the transistor T2. Means Z2, 30, T3, causes a potential, corresponding to the variable, decreasing, potential V, to be applied between the second resistor R2 and the transistor T2. The current to the transistor T2 is constant over a wide range dV for V, by a compensating current portion dI flowing through the second resistor R2, thereby maintaining V.sub. o constant.
    Type: Grant
    Filed: September 14, 1984
    Date of Patent: August 26, 1986
    Assignee: Ferranti plc
    Inventor: Andrew M. Mallinson
  • Patent number: 4603289
    Abstract: The invention is a dual input voltage regulator that has four active parts: a transistor, a resistor, a zener diode and a capacitor. It has one input for main power and one input for turn on power. The dual input allows lower main input voltage and allows the regulator to be synchronized with load.
    Type: Grant
    Filed: August 1, 1984
    Date of Patent: July 29, 1986
    Inventor: Norvel J. McLellan
  • Patent number: 4591728
    Abstract: A transformerless power unit for an electronic apparatus, preferably a horological instrument, including a fluorescent display, with a compensating resistor network which is connected with one pole of the supply voltage, preferably of a series circuit constituted of an ohmic impedance and a capacitor, with a rectifier diode, with a stabilizer for the stabilization of the output direct voltage, and with a charging capacitor which is connected in parallel with the output.
    Type: Grant
    Filed: March 8, 1984
    Date of Patent: May 27, 1986
    Assignee: Diehl GmbH & Co.
    Inventors: Tilmann Kruger, Werner Arnold, Leonhard Scheumann
  • Patent number: 4580206
    Abstract: A 12 volt input is supplied to a timer providing a square wave output with an approximately 50% duty cycle. The output is applied to the bases of a pair of transistors and the collectors of the transistors conduct when a drive motor is in either the forward direction or the reverse direction. During the time that a particular transistor is conducting, its collector current rises to a point of cutoff. At this time, energy stored in a transformer circuit is released to the secondary of the transformer circuit. To regulate the increase in voltage in the secondary, diode clamping is accomplished by a common string of zener diodes connected to the output of the secondaries of th transformer circuits and to the emitters of the transistors. By adding additional zener diodes in the secondary circuits of either of the transformer circuits, a change in the high voltage output for that particular transformer is accomplished.
    Type: Grant
    Filed: July 27, 1983
    Date of Patent: April 1, 1986
    Assignee: Xerox Corporation
    Inventor: Harry W. Lawson, Jr.