Abstract: The present invention relates to a power control apparatus. A feature of the power control apparatus of the present invention is that it discriminates whether an input signal in a circuit block to be controlled is active or inactive, and when it is determined that the input signal is inactive, it outputs a power-down signal to power down the circuit block.

Abstract: A lamp ballast circuit which provides a magnetizing inductance to a lamp ballast circuit transformer. A DC voltage and current supply source energize a pair of transistors which provide an AC voltage and current. The transformer includes a primary winding that receives the AC voltage and current. At least one lamp is coupled to the transformer secondary winding via a capacitor. The circuit has an optimal magnetizing inductance such that the transformer input voltage and current are substantially in phase with each other, thereby substantially reducing or eliminating the reactive power transferred through the output transformer. In a preferred embodiment, the magnetizing inductance, L102, is given as: L&khgr;=[1−(&ohgr;sC1R1)2]/n2&ohgr;s2C1, wherein &ohgr;s is an operating frequency, C1 is the capacitance of the capacitor, R1 is the resistance of the at least one lamp, and n is the secondary-to-primary side turns ratio of the transformer.

Abstract: A control system for controlling a solenoid valve driver used to drive a valve of a compression cylinder, including a power supply, a controller, and a first switching device having a first terminal connected to a first output terminal of the power supply, a second terminal connected to a coil of the solenoid valve driver, and a control terminal connected to a first output terminal of the controller.

Abstract: A programming circuit is coupled to an input/output pin of a device and is operative to generate a selected one of a plurality of electrical stimuli, such as a programming voltage, high and low logic levels, and a high impedance output, to the device in selected electrical state, without affecting normal device operation. The programming circuit includes a switchmode power converter, a linear regulator, and a control circuit. The programming voltage is generated by the switchmode power converter only when required for programming the device. The linear regulator includes a transistor having its collector-emitter path coupled in circuit with the switchmode converter and an output node, as well as to a voltage divider network. The voltage divider network is coupled to the control input of a precision shunt regulator device, which supplies a base reference for the transistor to establish the value of a voltage to be applied provided from the output node to the device.

Abstract: The invention provides a circuit for supplying electric power to a load using a high voltage battery, the circuit supplying a dark current when the load is not being operated. A high voltage load and a low voltage load are attached to a battery and electric power is supplied to the low voltage load through a main DC-DC converter and a sub DC-DC converter. When an ignition switch is OFF, only the sub converter supplies the dark current to the low voltage load and the main DC-DC converter is turned OFF. When the ignition switch is ON, the main DC-DC converter supplies required electric power. Since a low-capacity sub DC-DC converter supplies the dark current, the battery discharge can be prevented.

Abstract: A system and method for reducing a DC magnetic flux bias in a transformer and a power converter employing the system or the method. The power converter has a full bridge switching circuit coupled across a primary winding of a transformer and a hybridge rectifier circuit coupled across a secondary winding of the transformer. The transformer is subject to the DC magnetic flux bias as a result of an imbalance in the hybridge rectifier circuit. In one embodiment, the system includes: (1) a sensor configured to develop a signal representing the DC magnetic flux bias in the transformer; and (2) a controller, coupled to the sensor, configured to operate the full bridge switching circuit as a function of the signal thereby to reduce the DC magnetic flux bias.

Abstract: In a battery charger for charging a plurality of battery cells connected in series with each other with a constant current in a batch manner, the present invention is intended to suppress the generation of heat in cell shunt circuit sections which are provided as overheat protective measures for the individual cells. Surplus energy, which is generated in the cell shunt circuit sections by the product of a cell voltage and a shunt current and which becomes a heat generating source, is regenerated to a charger side via a flyback transformer provided in each of the cell shunt circuit sections, thereby suppressing heat generation.

Abstract: A switchable power supply includes a moveable electrical plug holding member that has a first position, which places an electrical plug pair in position for use with a first voltage standard, and a second position, which places the electrical plug pair in position for use with a second voltage standard. A switch is in a first state when the moveable electrical plug holding member is in the first position and is in a second state when the moveable electrical plug holding member is in the second position. When the switch is in the first state, a voltage modifier circuit generates a first output voltage and when the switch is in the second state, the voltage modifier circuit generates a second output voltage.

Abstract: A switching power supply circuit formed by providing a complex resonance type converter with a power factor improving circuit feeds back a voltage resonance pulse voltage generated in a primary-side voltage resonance converter to fast recovery type diodes via a tertiary winding or the tertiary winding and a series resonant capacitor by magnetic coupling to thereby improve a power factor to 0.9, and achieves an improvement in AC/DC conversion efficiency and a reduction in a ripple component of a direct-current output voltage by voltage doubler rectifier operation. Also, a first rectifier circuit and a second rectifier circuit shunt the current to be stored in a smoothing capacitor, so that a range of zero volt switching operation is not narrowed even when the power factor is improved.

Abstract: A system and method for developing a cost efficient electronic power supply system that handles a range of supported electronic circuits is provided. The electronic power supply system adaptively configures the power applied to electronic circuits. Thereby, eliminating redesign of a power supply system when a newly developed or different electronic circuit is implemented. When an electronic circuit is attached to the electronic power supply, a controller confirms electronic circuit presence and queries for electronic circuit power on requirements. As more electronic circuits are added, the controller examines each electronic circuit power on requirements and determines if a power conflict is present. If a conflict exists, the controller will not supply power to the electronic circuits until the conflict is resolved.

Abstract: An integral DC to DC converter for converting at least one input DC voltage into at least one output DC voltage is provided. The integral DC to DC converter includes a first input capacitor and a second input capacitor for providing the at least one input DC voltage, a DC to AC circuit, a transformer, a rectifying circuit, a filtering capacitor, two input DC voltage switching elements and an output voltage switching element. The integral DC to DC converter is implemented by switching the switching elements.

Abstract: A method for gauging a battery voltage of a portable terminal is disclosed, in which low voltage alarm and power cutoff time are determined by obtaining characteristic of a discharge curve slope of the battery, thereby improving reliability of the battery and increasing its available time. The method includes the steps of converting an analog voltage value, sampling the converted digital voltage value at a constant period, comparing the sampled digital voltage value with a predetermined number of previously sampled digital value to obtain a value of a discharge curve slope of the battery, and displaying remaining state of the battery depending on the obtained slope value.

Abstract: A load actuation circuit is provided which is capable of placing a limit on load current to a load below a predetermined value with high accuracy. In the load actuation circuit, a series circuit comprising a detection transistor and an NPN transistor is connected in parallel with an output transistor for supplying a load current to the load, and a diode is placed between the gates of the output transistor and the detection transistor for producing a voltage drop equal to a voltage drop in the NPN transistor. In addition, a constant-current circuit for supplying a constant current is connected to the gate of the detection transistor, and another transistor for constituting a current mirror circuit together with the NPN transistor is connected to the gate of the output transistor. This circuit arrangement prevents a limit value of the load current from fluctuating due to the non-uniformity of circuit elements or the like, thus achieving high-accuracy load-current limitation.

Abstract: The present invention provides electronic equipment that can shut off and supply power to a primary power supplying circuit by automatic operations, directly shut off power to the primary power supplying circuit by easy manual operations based on the operator's will, and never fails to zero power consumption of the primary power supplying circuit during no use.

Abstract: The invention relates to a DC/DC converter including a charge pump circuit comprising one or more capacitors and a plurality of controllable switches connected thereto, the controllable switches being controllable by a control circuit so that the capacitors is/are alternatingly switched in a charging and discharge phase; a first current source set to a predetermined base current located either in the discharge or charging path of the charge pump circuit and a second current source connected in parallel thereto; and a regulator circuit for generating a first control signal representing the difference between a voltage characterizing the output voltage and a first reference voltage and controlling the second current source when the charge pump circuit is active so that the controllable current is reduced or increased with an increase and reduction respectively in the difference to track the voltage characterizing the output voltage in accordance with the first reference voltage; and for generating a second cont

Abstract: This device for protecting a line (10, 12) of a network of supply lines comprises two protective relays (18, 20; 22, 24) furnished with means for detecting faults and a circuit breaker adapted so as to disconnect the line from the network of lines in the presence of a fault, each relay being adapted so as to monitor a first zone (Z1) of the line corresponding to a zone of certain detection of a fault (10, 12) and at least one second zone (Z2) juxtaposed with the first zone and corresponding to a zone of uncertain detection of a fault. At least one of the relays comprises means for detecting the opening of the circuit breaker associated with the other relay in response to a detection, by the latter, of a fault in the first zone in such a way as to cause the opening of the circuit breaker associated with the said at least one relay (18, 20; 22, 24).

Abstract: A DC-to-DC converter and a method thereof is provided. The DC-to-DC converter includes a power supply for providing a first direct current, a first capacitor, a first switch assembly for converting the first direct current into a first alternating current, a transformer for converting the first alternating current to a second alternating current, a rectifying circuit for converting and rectifying the second alternating current to a second direct current, a filtering circuit, and a range winding assembly for adjusting the output voltage of the second direct current in response to the voltage drop of the first direct current.

Abstract: An arc fault detector includes an average instantaneous current generator which averages the current over the fundamental period and produces a substantial output only where there are substantial variations in waveform between half-cycles which is indicative of an arc. To discriminate over inrush currents, a pulse generator generates a pulse in response to the step increase in current caused by striking of an arc. An output circuit generates an arc signal when the time attenuated accumulation of pulses occurring in half-cycles in which the average instantaneous current is above a selected threshold reaches a predetemiined level. To further discriminate over dimmers during turn on of a cold tungsten bulb, die ANDing with the average instantaneous current is delayed until a time attenuated accumulation of the pulses reaches a threshold value. The average instantaneous current can be approximated by a bandpass filter with a center frequency below the fundamental of the ac current.

Abstract: The inverter circuit can be structured by a simple structure as follows: an inductive element (the primary winding) 23 whose one end is connected to a DC power source 21; the first capacitor 24 connected in parallel with it; a serial circuit of the second switching element 27 and the second capacitor 25; a common connection point to which the primary winding 23, the first capacitor 24, and the other end of the serial circuit are connected; and the first switching element 26 to open and close control between the DC power source 21 and the other portion, are provided, and a drive signal generating means (resistance) is connected between the control terminal of the second switching element 27 and the common connection point.

Abstract: A buck switching DC-to-DC regulator having a resistor and capacitor in combination across the storage inductor to measure output current and voltage. The resistor connects to the input of the inductor and the capacitor to the output of the inductor. The junction of the resistor and capacitor connects to an error amplifier for controlling the switching regulator. The regulator may be paralleled for more output current by connecting the outputs together and providing a common reference voltage to all the regulators.