Abstract: In an inverter transformer, since a plurality of secondary windings 2, 2 are wound around a plurality of bar-shaped magnetic cores 3, 3 which are formed independently of each other and electromagnetically coupled to a primary winding 1 with equivalent characteristics, there are obtained a plurality of secondary windings 2, 2 which function independently of each other and are electromagnetically equivalent to each other as well, and an open magnetic circuit structure. It does not happen that the numbers of both the primary and secondary winding increase in proportion to the increase in the number of cold cathode lamps, but only the number of the secondary winding increases while the primary winding is common and does not increase in number.

Abstract: A multi-phase transformer system is provided having a main transformer fed by an N-phase voltage and a separate auxiliary transformer fed by the N-phase voltage. Windings in the main transformer are connected to secondary windings in the auxiliary transformer to provide pairs of connected windings. Each pair of connected windings has one of the windings of the main transformer and one of the secondary windings of the auxiliary transformer. The windings in such connected pair are arranged to produce voltages having different phases with each pair of windings producing an output voltage equal to the vector sum of the voltages produced by the such connected pair of windings. With such an arrangement, by having two separate transformers, i.e., the main transformer and the auxiliary transformer, fabrication of a multi-phase transformer system is simplified.

Abstract: The present invention relates to a bi-directional AC/DC converter having (i) a power stage, (ii) a sourcing control circuit and (iii) a recuperation control circuit. The converter operates with a Power Factor Correction in both directions, i.e. when transferring energy from the AC mains into the DC load as well as when it is transferring energy from an active DC load into the AC mains. Smooth transition between sourcing and recuperation is possible by allowing an active load to control the output voltage until the correct control circuit begins regulation.

Abstract: A semiconductor device includes a constant voltage generation circuit generating a constant voltage commonly to reference voltages corresponding to a plurality of internal voltages. The plurality of reference voltages are generated from the common constant voltage. Thus, the semiconductor device for generating internal voltages is implemented, which allows reduction in layout area and decrease in test time for voltage adjustment.

Abstract: In a continuous mode flyback converter an FET transistor (110) is provided for reducing the voltage drop at the secondary side of the transformer. The use of the FET transistor makes the converter more suitable for low voltage applications since smaller power losses are imposed in the secondary side of the converter than in a conventional converter. The converter also has a DC-blocking capacitor (117) for further reducing the power losses at the secondary side.

Abstract: A voltage supply control apparatus, suitable for being applied to a low voltage operation device. The voltage supply control apparatus has a high threshold voltage transistor and a low threshold voltage transistor. When the low voltage operation device is not working, the low threshold voltage transistor is cut off, and the voltage drop of a high voltage received from the power source terminal of the low voltage operation device is controlled by the high threshold voltage transistor. In contrast, when the low voltage operation device is working, the operation enable signal output thereby conducts the low threshold voltage transistor to control the voltage drop of the high voltage received from the power source terminal, so that a high potential is obtained.

Abstract: An overvoltage protector assembly utilizes a gas tube having an electrically conductive terminal and an electrically conductive end cap for being selectively brought into electrical contact with the terminal to divert surges to ground. A toroidal non-conductive element having a central hole is disposed between an end cap and the terminal of the gas tube. A fusible element formed of a fluxed solder pellet is also disposed between the end cap and the terminal of the gas tube. The end cap includes at least one aperture and a raised projection on its outer surface so that axial forces applied by a spring clip are centrally applied to the end cap. Molten solder flows through the central hole in the non-conductive element and the aperture in the end cap when the overvoltage protector assembly overheats so that the end cap and the terminal are in electrical contact.

Abstract: The invention concerns a dc-to-dc converter controlled by a rectangular signal comprising an input for a direct voltage source (VDC), a transformer comprising a primary coil (1) connected to the direct voltage source (VDC) and a D2 secondary coil (2), a single switch (S) series-connected with the primary (1) and the direct voltage source (VDC), an output comprising the transformer secondary (2) and at least a tertiary coil (3) located in the proximity of the primary (1) and secondary (2) coils at the transformer core series-connected with a first diode (D1).

Abstract: An accessory includes a trip arm biased by a spring to pivot in a clockwise direction about a trip arm pivot. A latch is arranged to pivot about a latch pivot and has the trip arm acting on a latch surface on the latch to bias the latch in a counter clockwise direction about the latch pivot. An electromechanical device including a plunger acts on the latch pulling it clockwise about the latch pivot. When a signal is provided to the electromechanical device, the plunger is released allowing the trip arm to pivot clockwise about the trip arm pivot due to the spring and actuates the operating mechanism. To reset the trip arm and the latch, a reset lever is arranged to pivot about the latch pivot. The reset lever includes a tab portion configured for interfacing the operating mechanism, and a drive portion for interfacing the trip arm. This, when the operating mechanism is reset, a portion extending from an operating handle interfaces the tab portion to pivot the reset lever clockwise about the latch pivot.

Abstract: The present invention relates a current zero crossing detecting circuit including a PWM driving half bridge circuit, which generates an output signal (OUT) and a signal synchronous with the high impedance condition of said PWM driving half bridge circuit. Said inventive circuit has the characteristic of comprising detecting means (DFLIP, COMP) synchronous with said signal synchronous with the high impedance condition of said PWM driving half bridge circuit and said output signal (OUT), and said detecting means generating a direction signal (DIR_COR) showing the current direction flowing in said pulse width modulation circuit.

Abstract: A power supply apparatus employs a unidirectional unit equipped with a diode, a bypass switch connected in parallel to the diode, and a controller which turns the bypass switch ON when a forward voltage appears in the diode in order to rectify or prevent the backflow of the power from a power generating unit built in portable electronic equipment of an arm-worn type or the like; it is able to eliminate almost all loss caused by the forward voltage at the time of power supply. The elctromotive force of the power generating unit incorporated in arm-worn type electronic equipment ranges from almost the same level to about a few times the level of the forward voltage; hence, the use of the unidirectional unit enables rectifying efficiency to be markedly improved.

Abstract: To easily and quickly return from a power-off state, as well as reducing power consumption of an electrical apparatus by an automatic power-off, a power supply source connection controller 10 comprises: a power source connecting switch R0-2; a relay R0 for controlling the opening and closing of the switch R0-2; control switches SW1, SW2, and SW3 for sending a signal to a microcomputer 72 to provide instructions for executing a predetermined function, as well as connecting a power supply circuit 74 to the relay R0; a connection holding switch R0-1 for holding a connection between the relay R0 and the circuit 74; and a connection releasing switch SW0 for releasing a connection between the relay R0 and the circuit 74.

Abstract: A load drive circuit for an electric load comprises a plurality of switching circuits connected in parallel with each other, a first wiring conductor pattern connecting one sides of the switching circuits to an external power side through a first connecting portion, and a second wiring conductor pattern connecting another sides of the switching circuits to a load side through a second connecting portion. The first connecting portion and the second connecting portion are disposed in the vicinity of one end and the other end of a parallel arrangement of the switching circuits, respectively. Current paths from the first connecting portion to the second connecting portion through the switching circuits, respectively, have substantially same resistances.

Abstract: The present invention provides a PWM control apparatus which makes it possible to obtain a high-precision, high-S/N-ratio, low-cost, small-volume, light-weight motor driving apparatus. In particular, to provide a motor driving apparatus using this PWM control apparatus, a stage apparatus using this motor driving apparatus, an exposure apparatus using this stage apparatus, a device manufactured by means of the exposure apparatus, and a device manufacturing method.

Abstract: A DC-DC converter having a switching element and a synchronous rectifier, the switching element undergoing a switching operation, the converter performing a voltage conversion of an input voltage to provide a converted output voltage at an output/input conversion ratio that is determined by the switching operation of said switching element, the converter delivering the converted output voltage to a load, said DC-DC converter further comprising: a reverse current detector for detecting a reverse current which flows from an output of the converter to an input of the converter, and a reverse current suppressor, the reverse current suppressor controlling the switching operation of said switching element so as to increase the output/input conversion ratio when a reverse current is detected by the reverse current detector, thereby suppressing the reverse current.

Abstract: An object is to provide a word line boosting circuit which, regardless of varying value of the power-supply voltage, can generate a boosted voltage within a range between upper and lower limit values of threshold voltage distribution of semiconductor non-volatile memory elements. A drain boosting circuit (VCa) has a plurality of series-connected boosting stages and the number of parallel-connected capacitors is varied in each stage depending on the value of the power-supply voltage (Vcc). Comparators (OP1) to (OP3) detect resistor-divided voltage values to detect the power-supply voltage (Vcc). A decoder (DCa) generates operation signals (S1a) to (S3a) in accordance with the combination of outputs of the comparators (OP1) to (OP3), thus determining which capacitors should be connected in parallel.

Abstract: A charge pump DC/DC converter with reduced noise at the input voltage source is provided. The present invention includes buck and boost DC/DC converters with added circuitry coupled between the input voltage and the switches which maintains a substantially constant input current on both phases of the charge pump clock. The added circuitry reduces input current variations to provide reduced noise at the input voltage source. Feedback loop circuitry coupled between the output node and the added circuitry varies the current through the switches to control the output current of the DC/DC converter in order to maintain the output voltage at the regulated value. The added circuitry may comprise a variable resistor, current mirror, or current mirrors.

Abstract: A high voltage direct current transmission system has a first and a second converter station coupled to each other via a direct current link, each converter station with a voltage source converter. The first converter station has a first voltage sensing device for sensing its direct voltage, and a voltage controller for control of its direct voltage. The second converter station has an active power controller for control of its active power flow in dependence on a reference value therefor. The voltage controller controls the direct voltage of the first converter station in dependence on only a sensed instantaneous value of the direct voltage and a first voltage reference value therefor, for a voltage control that is independent of the flow of active power through the first converter. The second converter station includes a second voltage device for sensing its direct voltage.

Abstract: In an upconverter operating in the transient mode, an offset signal is added to the signal at the current sensing pin of the control IC. The upconverter generates a comparatively low THD even if the supply voltage and/or the power supplied by the upconverter are varied over a wide range.

Abstract: The present invention relates to a current limiting circuit for controlled semiconductor power components, in particular to a current limiting circuit for power transistors which is independent of its voltage supply. A current limiting circuit for controlled semiconductor power components, in particular for power transistors, with a sense resistor, which is connected in series with the main current path of the controlled semiconductor power component, generating a voltage drop proportional to the current through the controlled semiconductor power component. A current mirror circuit device has a first current source device for generating a first current between a first and a second reference-ground potential. A second current source device generates a second current between the control potential of the control terminal of the semiconductor power component and a third reference-ground potential.