Did You Know...
...that the Eveready Battery began as an invention called the "electric flowerpot," which was a tube with a battery and light bulb inside? The idea was to fasten this gizmo to the side of a flowerpot so it would illuminate the flowers from the bottom. The idea died on the vine and the businessman who licensed the flower pot, Conrad Huber, was left with a pile of useless tubes -- until he found a way to market them as batteries to light the world!
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| Number | Title | Issue Date |
| 7460378 | Overload protection arrangement for electronic converters, for instance for halogen lamps A circuit arrangement for protecting an electronic converter against overloads includes: a low impedance path selectively activatable to prevent ignition of the electronic converter, the low impedance path including an electronic s... | 12/02/2008 |
| 7042740 | Soft-switching half-bridge inverter power supply system An inverter power supply system includes a half-bridge inverter circuit which includes a first switching element, a second switching element, a first auxiliary capacitor and a second auxiliary capacitor for converting a DC voltage from a DC power supply circuit to a... | 05/09/2006 |
| 7005924 | Current limiting circuit with rapid response feedback loop The current limiting circuit of the present invention includes a transconductance amplifier having two outputs and forming a conventional feedback loop. A first output connects to an output transistor and a second output is a replica output used to form a rapid resp... | 02/28/2006 |
| 6909619 | Spike control apparatus for DC-DC converter There are disclosed a synchronous rectifying type of DC—DC converter, a DC—DC converter control circuit constituting such a type of DC—DC converter, a monitor circuit for monitoring an operation of a DC—DC converter, and an electronic equipment having a DCâ€... | 06/21/2005 |
| 6744643 | Push-pull booster circuit with a pair of inductors for coupling A modified push-pull booster circuit is proposed, wherein two alternately switching transistors are disposed on the primary winding of a transformer, and a bridge rectifier and a charging circuit are disposed on the secondary winding; wherein the bridge rectifier ha... | 06/01/2004 |
| 6687142 | AC to DC inverter for use with AC synchronous motors AC to DC inverters that are formed from electronic switches, such as MOSFETs, that are controlled by gating pulses obtained from comparators. The comparators compare a varying signal against two closely spaced reference voltages so as to provide gating pu... | 02/03/2004 |
| 6449172 | Switching power supply with nonlinear characteristics at start up A power supply apparatus includes a variable frequency oscillating circuit, a driver, a soft start circuit, switching elements for receiving a switching signal, a resonating capacitor connected at a connection point of the switching elements via a primary... | 09/10/2002 |
| 5898580 | Dc/dc converter with a protection circuit The invention is about a dc/dc converter (1) fitted with switching means (11, 12) having a drive electrode (13, 14) each drive electrode (13, 14) being connected to polarization means (49,50). The switching means are to switch on and off a current coming ... | 04/27/1999 |
| 5895983 | Flash charging circuit A flash charging circuit has first and second transistors (TR1, TR2) which are connected to opposite terminals of a primary coil of a transformer, a battery is connected to a center tap provided in a middle portion of the primary coil, and first and secon... | 04/20/1999 |
| 5303137 | Multiresonant self-oscillating converter circuit A direct current to direct current converter utilizes a MOSFET half-bridge configuration in which the inherent magnetizing and leakage inductances of the transformer are used as the only inductances in the frequency-determining circuit. Diodes are used to... | 04/12/1994 |
| 5262932 | Power converter In one embodiment, a solid state DC power supply includes an inverter (30) having two half-bridges (32, 34) in which are provided pairs of MOSFETS (Q5-Q12) used as switching elements. An output transformer (60) and a rectifier (85) are connected to output... | 11/16/1993 |
| 5162981 | Low voltage D.C. to D.C. converter A circuit for converting on d.c. voltage to another d.c. voltage including a transformer having a center tap and first and second end leads. A d.c. source voltage is connected to the center tap of the transformer. The end leads are connected to ground thr... | 11/10/1992 |
| 5017756 | Method and apparatus for preventing chain reaction transistor failure in paralleled transistors An improved electronic welding station is disclosed. The welding station provides for an improved arc striking capability by providing a higher arc striking voltage and a large arc striking current and, once the arc is struck, automatically switches over ... | 05/21/1991 |
| 4941076 | Start-up circuit for a high voltage DC to AC converter A four-quadrant buck converter is described having a common leg of an inductor in series with an output capacitor, one power supply for providing a positive voltage output signal and negative voltage output signal to two solid-state switches joined at a c... | 07/10/1990 |
| 4920471 | AC high voltage power supply The invention relates to a high voltage AC power supply which can be operated as either a constant current source with overvoltage protection or as a constant voltage source with current limiting protection. The power supply includes a sinusoidal transfor... | 04/24/1990 |
| 4858096 | Resonant converter for stabilized operation of switching devices An impedance for short-circuit prevention is connected with a secondary winding side of a transformer of a resonant converter comprising a resonant circuit, a D.C. input source, and a switching devices. The short-circuit prevention impedance is driven by ... | 08/15/1989 |
| 4855858 | Power regulator with overcurrent protection A regulator includes a switching transformer (TR) whose primary winding is divided into two halves through which current flows alternatingly via one respective switching transistor (Q1, Q2). The pulses on the secondary side of the transformer are rectifie... | 08/08/1989 |
| 4843532 | Regulating pulse width modulator for power supply with high speed shutoff A switching power supply includes push-pull power switches driven by first and second conjunction gates. The conjunction gates are coupled to receive the output of a flip-flop, together with the antiphase outputs of a binary divider which divides down the... | 06/27/1989 |
| 4827150 | Uninterruptible power supply inverter circuit An inverter is provided, especially for use in an uninterruptible power supply, with its switching transistors being ground referenced and its output voltage fed back and compared to a single reference waveform for a self-setting duty cycle control of the... | 05/02/1989 |
| 4805080 | Power supply circuit for an X-ray tube The invention relates to a power supply circuit for an X-ray tube for converting direct current to high-frequency pulses and including at least two transistors (8, 9) whose collector-emitter circuits are controlled by means of a pulse-width modulator (5) ... | 02/14/1989 |
| 4760484 | Protective inductive devices with increased ability to absord volt-seconds in an electrical conductor An inductive device composed of a bead of magnetic material, such as ferrite, has an aperture through which an electrical conductor is adapted to pass. The bead is formed unsymmetrically about at least one axis. The asymmetry of the bead alters the magnet... | 07/26/1988 |
| 4755923 | Regulated high-voltage power supply An inventive regulated high-voltage power supply circuit comprises a push-pull oscillation circuit (30) including two transistors (TR4, TR5), a control circuit (20) for controlling voltage to be supplied to the oscillation circuit, a short detecting circu... | 07/05/1988 |
| 4742441 | High frequency switching power converter A high-frequency switching power conversion circuit is disclosed. The circuit is capable of operating either as an inverter or as a rectifier, by the use of an array of high-power, bidirectional switches. AC waveforms are produced by ROM-based pulse width... | 05/03/1988 |
| 4725937 | Low power dissipation analog current loop output circuit A method and apparatus for controlling the magnitude of an analog current through a load to be proportional to the magnitude of an input voltage. A sensing resistor is connected in series with the load. A controllable voltage is applied across the series ... | 02/16/1988 |
| 4694387 | Inductive devices An inductive device composed of a bead (10) of magnetic material, such as ferrite, has an aperture through which an electrical conductor (13) is adapted to pass and a reset winding (14) wound thereon and connected to a source of constant current. The cons... | 09/15/1987 |
| 4639845 | Voltage inverter A voltage inverter is disclosed. A clock circuit provides timing signals to the electronics of the system. Electronics include a circuit for controlling the phase relationship between a pair of square waves, an overcurrent protection circuit, an auto-on c... | 01/27/1987 |
| 4564800 | Battery charger A switch-mode battery charger in which a pair of field effect transistors are operated at a relatively high switching rate. Protection against excessive overload is provided by directly monitoring the pulse trains produced by the transistors rather than t... | 01/14/1986 |
| 4558230 | High integrity dual input power supply A high integrity multiple output power conditioner operating from redundant dc sources utilizes circuits to combine the sources to share a load and provide source isolation in event of component failure in any one of plural converters employed. Multiple g... | 12/10/1985 |
| 4542440 | Switch current sensing with snubber current suppression in a push-pull converter A push-pull converter has transistor power switches which conduct alternately to connect a DC source with the primary windings of an output transformer. A turn-off snubber circuit is connected with each power switch. When a power switch is turned on, snub... | 09/17/1985 |
| 4524412 | Peak current controlled converter with additional current threshold control level to limit current tailout during overload conditions A power converter circuit, which is voltage-regulated and current-limited by a peak current control circuit, significantly reduces the current tailout effect by decreasing the frequency of operation of the converter during low voltage output current-limit... | 06/18/1985 |
| 4464709 | Current and voltage protection for a power supply circuit A power supply circuit comprises a main transformer having a primary winding and a secondary winding, a series resonance circuit coupled to the primary winding of the main transformer, and a switching circuit for alternately supplying DC power to the seri... | 08/07/1984 |
| 4462069 | d.c. To d.c. voltage regulator having an input protection circuit, a d.c. to d.c. inverter, a saturable reactor regulator, and main and auxiliary rectifying and filtering circuits A multiple output d.c. to d.c. regulating circuit including an input protection circuit for providing protection against input overcurrent, input transient voltages, sustained input overvoltage and input polarity reversal. The protection circuit powers a ... | 07/24/1984 |
| 4456950 | Current spike protection circuit for switch-mode power supplies A circuit which prevents the flow of excess spikes of magnetization current in the primary windings of a transformer used in a switch mode power supply is disclosed. The circuit comprises an AC coupled, peak detecting, negative feedback path from a curren... | 06/26/1984 |
| 4453193 | Overcurrent protection for push-pull circuits Overcurrent protection is obtained in a push-pull network by circuitry repeatedly comparing signals indicative of the instantaneous current flow through the push-pull switching elements with a synchronized reference signal whose value is preferably made t... | 06/05/1984 |
| 4429356 | Transistor inverter device Base current is supplied from a base driving circuit to bases of paired inverter transistors through a transistor, and an inverter circuit oscillates at a rated output. When the operation of an electric discharge lamp becomes abnormal, an IC-ed control ci... | 01/31/1984 |
| 4384320 | Push-pull switching mode inverter-type power supply A system is provided for driving the switching transistors in a push-pull switching mode inverter-type power supply. The system of the invention provides drive current adjusted to the actual power supply load throughout the entire switching cycle from tur... | 05/17/1983 |
| 4369491 | Protective circuitry for transistorized d-c/d-c converter A d-c/d-c converter has two switching transistors connected in push-pull across respective primary halves of an output transformer working into a full-wave rectifier, these primary halves lying in parallel with the primary of a self-saturating feedback tr... | 01/18/1983 |
| 4359679 | Switching d-c. regulator and load-sharing system for multiple regulators In a system of parallel switching regulators sharing a common load, each regulator generates controllable pulses from an unregulated d-c. voltage source and then smoothing those pulses to form a d-c. output that varies according to changes in the pulses. ... | 11/16/1982 |
| 4356543 | Overcurrent-protected inverter A battery pack-containing solid state circuit, normally in a standby condition, automatically applies battery-generated power to a multi-power requirement load a predetermined time period subsequent to detection of a malfunction in the load's normal power... | 10/26/1982 |
| 4342076 | Transistor turn off current sensing circuit A transistor current sensing circuit is provided for a power output transistor whose drive circuit includes a current controlled feedback transformer that has a current limited direct current source connected to the secondary winding of the transformer wh... | 07/27/1982 |
