Famous Patents
In 1608, Dutch eyeglass maker Hans Lipperhey filed the first patent for a working telescope. The patent was denied.
PatentStorm News
Make the Most of Our Site
See this month's Top Inventors and Most Cited Patents.
Stay on top of the latest innovations by subscribing to an RSS feed.
Registered users: Manage your profile.
| Number | Title | Issue Date |
| 7843674 | Motor drive circuit A motor-drive circuit comprising: a current-passage-control circuit to perform ON/OFF control of a drive transistor connected to a motor coil to pass current through the motor coil; an overcurrent-state-detection circuit to detect whether current passing through the... | 11/30/2010 |
| 7817392 | Insulated gate bipolar transistor fault protection system An Insulated Gate Bipolar Transistor (IGBT) fault protection system is provided. The fault protection system includes a GVPA, a gate voltage clamper, and a soft-off unit. The GVPA analyzes a gate voltage pattern of an IGBT to determine whether or not a fault has occ... | 10/19/2010 |
| 7495875 | Power abnormal protection circuit A power abnormal protection circuit includes a power detection unit, a voltage drop correction unit, a drop out detection unit, a delay unit and a delay masking unit. By detecting an input power average value of a power supply occurring of a brown out condition can ... | 02/24/2009 |
| 7292073 | Transmission line driver circuit A transmission line driver circuit that operates at a first voltage level is fabricated using devices that operate at a second, lower voltage level. The driver circuit includes a ramp generator that receives a speed signal and a data signal and generates a charge ra... | 11/06/2007 |
| 7276968 | Class D amplifier A drive signal that matches the bias of a transistor is generated. A differential amplifier calculates the difference between a specified voltage of negative power supply and another input signal. Then, a resistor that realizes a pull-down function level-shifts it t... | 10/02/2007 |
| 7209330 | Reset lockout for circuit interrupting device Resettable circuit interrupting devices, such as GFCI devices, that include a reset lock-out mechanism are provided. The reset lock-out mechanism prevents the resetting of electrical connections between input and output conductors if the circuit interrupting mechani... | 04/24/2007 |
| 7199989 | Digital protection relay with time sync function In a digital protection relay with a time sync function, the sampling timing of which is specified based on a reference timing transmitted from a time signal generator to a time sync unit, with a determination value. The time sync unit includes a reception circuit t... | 04/03/2007 |
| 7119549 | Output calibrator with dynamic precision An integrated circuit device having an output driver circuit and a control circuit. The output driver circuit outputs a first signal having a signal level according to a control value. The control circuit is coupled to receive the first signal from the output driver... | 10/10/2006 |
| 7099135 | Integrated inrush current limiter circuit and method An inrush current limiter circuit (20) includes a detection circuit (30) that produces a control signal (VDRIVE) from a sense current (ISENSE). A power transistor responds to the control signal and has a source (51) coupled... | 08/29/2006 |
| 6831433 | Drive control apparatus A drive control apparatus comprises a drive signal supply unit for generating, when a power-supply voltage is supplied to the drive control apparatus, a drive signal, which is used for driving a load from this power-supply voltage, and for supplying this generated d... | 12/14/2004 |
| 6680836 | Timed tripping circuit for an electromechanical switching device An electromechanical switching device can be tripped in a quick and reliable timed manner. The timed tripping circuit includes a voltage-sensitive switching element which separates an energy storage mechanism from the switching device when the supply volt... | 01/20/2004 |
| 6680834 | Apparatus and method for controlling LED arrays A high precision, high efficiency controller for LED devices such as LED arrays includes a current limiter, driver and buffer.... | 01/20/2004 |
| 6486570 | Waveform correction filters A waveform correction filter is connected into an alternating current power line to absorb and remove various forms of power pollution, including high-frequency spikes, surges and other forms of high-frequency oscillations, such as those which result from... | 11/26/2002 |
| 6351083 | Circuit for selective power supply to electrical units A circuit is provided for selectively providing electric supply voltage from an input feed line with a neutral conductor, a phase conductor and optionally an earth conductor to individual or parallel-connected groups of connected terminals each comprising... | 02/26/2002 |
| 6275093 | IGBT gate drive circuit with short circuit protection An IGBT gate driver circuit includes means for detecting when the collector-to-emitter voltage (Vce) of a turned-on IGBT, intended to be operated in the saturation region, increases above a preset level, indicative of a fault condition, such as a short ci... | 08/14/2001 |
| 6118642 | Electronic regulation circuit for driving a power device and corresponding protection method of such device An electronic regulator for driving a power device connected to an output load having a first portion and a second protection portion, the first portion including a controlled switching element connected upstream of the power device and controlled by a ti... | 09/12/2000 |
| 6108182 | Overcurrent sensing circuit and self adjusting blanking A sensing circuit 100 includes two resistors 11 and 12, two pnp transistors 13 and 14, and a current mirror 15 and 16. Resistors 11 and 12 convert the high voltages present in the bridge into a proportional current. The current mirror, mosfets 15 and 16, ... | 08/22/2000 |
| 6028420 | Constant voltage power supply with continuity checking A constant voltage power supply includes one or more sense leads connected to a load and in a feedback control loop. The voltage at the load is fed back via the sense leads for comparison to a reference voltage in the loop to generate an error signal that... | 02/22/2000 |
| 6028754 | System for preventing undesired protective relay tripping actions due to coupling capacitor voltage transformer transients The system impedance ratio (SIR) is determined for the original zone 1 distance element reach of a protective relay. The reduction in the original zone 1 reach is then determined, using the SIR value and a known table of reduced values. When a fault is re... | 02/22/2000 |
| 5986361 | Automated electronically controlled microsprayer An electronically controlled micro-dispensing apparatus (10 or 210) is described. The apparatus includes a liquid storage container (12), a propellant container (16), a control circuit (34 or 42) and an ejector (28). In a second embodiment, the liquid and... | 11/16/1999 |
| 5731812 | Liquid crystal display (LCD) protection circuit A display protection circuit includes a first OR gate which receives a first pulse at one input and a first clock signal at another input. A second OR gate receives the first pulse at one input and a second clock signal at another input. A first monostabl... | 03/24/1998 |
| 5708549 | Integrated circuit having enhanced transient voltage protection and associated methods An integrated circuit includes protected circuit portions for being electrically connected to an electronic circuit via electrical conductors, and a multiple time constant transient clamping circuit for clamping a transient voltage based upon one of first... | 01/13/1998 |
| 5703745 | System for detection of transients from a coupling capacitor voltage transformer used in a protective relay The voltage and current conditions on a power transmission line are monitored to determine the coincidence of a low voltage condition and a lack of a high current condition. The coincidence of those two conditions is indicative of a CCVT transient, and th... | 12/30/1997 |
| 5666081 | On-delay circuit The present invention relates to a fail-safe on-delay circuit which uses an an electronic circuit. An input signal higher than a power source potential is input to a PUT oscillating circuit and a pulse signal generated with a predetermined time constant, ... | 09/09/1997 |
| 5602709 | High impedance fault detector A method and apparatus for detecting high impedance faults and other arcing phenomena in an electrical distribution system. Electrical signals on the distribution system are monitored and a number of frequency components isolated, such as zero-sequence cu... | 02/11/1997 |
| 5532895 | Overload protection device An overload protection device is to be used in a current-carrying circuit which includes an AC power source and at least one load. The overload protection device includes a resistor, a transformer and a control circuit. The resistor is to be connected to ... | 07/02/1996 |
| 5457591 | Current overload protection circuit In a current overload protection circuit, a full wave rectifier bridge circuit is connected between an AC or DC power source to supply AC or DC power to a load through the output circuit of a solid-state relay. A current sensing resistor is connected acro... | 10/10/1995 |
| 5448441 | Fault protection circuit for power switching device A fault protection circuit for a power switching device. The circuit compes a driver circuit electrically connected to the power switching device, a saturation comparator electrically connected to the collector of the switching device to determine if the... | 09/05/1995 |
| 5430596 | CRT protector circuit A CRT protector circuit for detecting an overcurrent or an overvoltage to a CRT to protect the CRT. A detector circuit is provided for detecting the overcurrent and the overvoltage, and when such is detected an abnormality detection output from the detect... | 07/04/1995 |
| 5428492 | Current driver having voltage transition failure-based short circuit protection circuit A current driver has a short circuit protection circuit which monitors the magnitude of the current driver's output voltage. The protection circuit looks for the failure of the output voltage to either change to a prescribed non short-circuit representati... | 06/27/1995 |
| 5424894 | Electrical line-fault detector and circuit breaker device An electrical circuit breaker device for connection between a load device and a power source, capable of disconnecting the load device from the power source upon detection of an electrical fault condition present in the wiring between the load and the pow... | 06/13/1995 |
| 5166854 | Externally discernible power supply abnormality detection system A power supply abnormality detection system of the present invention includes a low-frequency power amplifier circuit equipped with a built-in overvoltage protection circuit for detecting a voltage exceeding, for example, a reference power supply voltage.... | 11/24/1992 |
| 5142165 | Power off/on delay circuit to prevent lockout The present off/on delay circuit operates within the power supply of a microcomputer system to interrupt transfer of regulated DC voltage to the system microcomputer and attachments in respect to indications of power disturbance and system switch status p... | 08/25/1992 |
| 5105182 | Direct current power supply device having an alarm provided for power failure under varying load conditions A direct current power supply device which generates an alarm signal when a power failure occurs in an alternating current power supply connected as an input to the device. A power failure detector circuit is connected at the input of the device and signa... | 04/14/1992 |
| 5105324 | Device for protecting semiconductor circuits against transients on the supply line A series of Zener diodes (25) and an electronic power switch, such as an IGBT (18), are connected across a power supply. A circuit including a resistor (20) in series on the electronic switch, a threshold device (36, 38) connected to the resistor and a ra... | 04/14/1992 |
| 5073724 | Programmable inverse time delay circuit An inverse time delay circuit includes an integrator for receiving a signal representative of a voltage or current in an external circuit and a reference signal. The integrator produces a control signal representative of the integral of the difference bet... | 12/17/1991 |
| 5041940 | Power transistor control circuit particularly for switching incandescent lamps A method and apparatus for switching an electrical load, such as an incandescent lamp, with a FET and providing protection for the FET. An exponential reference signal is generated which is a function of drain to source voltage and represents the integral... | 08/20/1991 |
| 4987513 | Apparatus and method for selectively delaying the connection of an electrical supply voltage to an electrical load An apparatus and method for delaying the reconnection of an electrical supply voltage to an electrical load when the supply voltage has been restored after an interruption. In its basic form, the apparatus comprises a circuit interrupter coupled between t... | 01/22/1991 |
| 4970620 | FET bridge protection circuit An FET bridge protection circuit preventing shoot-through caused from both FETs being biased on at the same time, while also maximizing the frequency at which the bridge output can alternate between high and low is described.... | 11/13/1990 |
| 4958055 | Control circuit for a refrigerator combined with a microwave oven A control circuit for a refrigerator combined with a microwave oven includes signal delay selecting and comparing circuitry start sensing circuitry timer circuitry and load driving circuitry in order to properly control operations of the refrigerator and ... | 09/18/1990 |
