Abstract: A multi-level voltage regulator system/method providing discrete regulation of a DC-DC intermediate bus converter (IBC) output voltage (Vout) is disclosed. The disclosed system/method allows IBC Vout to be regulated in discrete steps during periods where IBC input voltage (Vin) falls below nominal operating values. Rather than shutting down or degrading IBC Vout in an unpredictable non-linear fashion based on IBC input/loading, IBC Vout is regulated in fixed discrete steps, allowing IBC-connected point-of-load (POL) converters to obtain stable power input that is well-defined over IBC Vin. IBC operating parameters may define multi-dimensional operational state spaces of IBC Vout regulation that ensure optimum power flow to attached POLs while maintaining operational stability within the IBC regulator. Instabilities in IBC /POL performance across variations in IBC Vin, load transients, POL loading, and environmental variables may be prevented using Vin voltage step hysteresis.

Abstract: The improved DC-DC converter apparatus includes a primary side circuit and a secondary side circuit that is galvanically isolated from the primary. The primary side induces a voltage in the secondary side that provides an output voltage for driving POLs. A controller in the primary senses a reflected output voltage signal that is coupled from the secondary and is proportional to the secondary output voltage with respect to a voltage regulation point determined by either a voltage divider circuit or the zener voltage in the secondary. The voltage regulation point is established by wide-tolerance electrical components, such as a zener diode, a resistor, or a combination, connected in the coupling device circuit.

Abstract: A controller controls a voltage-source power converter and a current-source power converter based on a detection value of a rail voltage input to the voltage-source power converter and a detection value of a charging voltage output from the current-source power converter, at the time of charging operation.

Abstract: A controller controls a voltage-source power converter and a current-source power converter based on a detection value of a rail voltage input to the voltage-source power converter and a detection value of a charging voltage output from the current-source power converter, at the time of charging operation.

Abstract: An LED drive device whose power dissipation can be effectively reduced without halting current supply to an LED row as well as an LED illuminating device with the LED drive device incorporated therein. When an LED 21A making up an LED row 3A has developed a short-circuit fault, a voltage corresponding to a forward voltage which has been applied to the faulty LED 21A is impressed additionally to an FET 31A for electric power consumption thereof to increase to not less than a certain value. At this time, a power limiting circuit 6A varies a potential, being a reference value of a constant current circuit 7A, at a connecting point between voltage dividing resistors 46A, 47A and then continues to supply a certain level of a current IF1 to the LED row 3A so as to keep the remaining fault-free LEDs 22A to 26A lighting. Consequently, in the event of a short-circuit fault of the LED 21A, the adverse effect caused by discontinuing the current supply to the LED row 3A can be swept away.

Abstract: A number of cells can be determined before control for a battery without providing cell number setting and input means. The cell number determination device comprises voltage measuring units that select an “i”th cell among cells that are connected in series and that configure a battery, and that measure a voltage value between a terminal in which the “i”th cell and an (i?1)th cell, which is in one location higher than the “i”th cell, are connected and a ground potential line, voltage comparators that determine an existence, nonexistence or normality of the cells by comparing a voltage value of an (i+1)th cell that is in one location lower than the “i”th cell with the voltage value of the “i”th cell measured by the voltage measuring units and a cell number determination unit that determines a number of assembled cells and normal cells and cell assembled locations in the battery.

Abstract: A load drive device capable of expanding a range of an output power by improving a linearity thereof when the output power varies.

Abstract: A DC-DC converter includes a current-source power converter that converts direct current into alternating current; a transformer that transforms the voltage of the alternating current output from the current-source power converter; a rectifier that converts the alternating current the voltage of which has been transformed by the transformer, into direct current; and a capacitor that is connected in series with winding of the transformer on the rectifier side, and blocks a direct-current component from being applied to the transformer.

Abstract: The present invention provides a non-intrusive method for dissipating heat from open-frame DC-DC power converters where bottom side components are exposed. A thermal interface material is placed between the motherboard to which the power converter is soldered and power dissipating and temperature sensitive components on the bottom of the power converter. The thermal interface material fills the gap between the power converter components and the motherboard, thereby providing a heat conductive path for dissipating heat from the power converter to the motherboard.

Abstract: A discharge lamp lighting device capable of preventing magnetic saturation of an inductor connected with an output of an inverter. An inverter 12 comprises a first set of switching elements 32, 33 for switching an output voltage of the inverter 12 to a positive polarity and a second set of switching elements 31, 34 for switching the output voltage thereof to a negative polarity. At the start-up of a lamp 20, each of the switching elements 31 to 34 is allowed to perform switching operations in such a pattern that after turning on and off the first set of the switching elements 32, 33 more than once, the second set of switching elements 31, 34 are allowed to turn or and off more than once. Accordingly, energy stored in the inductor 37 is discharged during a temporary off-period, thus permitting the inductor 37 to be prevented from being magnetically saturated.

Abstract: A reusable period of a battery can be maintained for a long time by recharging while avoiding abnormal heating of the battery due to over discharge. A battery protection circuit comprises a control part that cuts off a discharge switch which is a discharge path to a load for a battery when a voltage value of the battery is equal to or less than a first threshold value, or when the voltage value of the battery is less than the first threshold value, wherein the control part cuts off a power switch as a power supply path to the control part itself when the voltage value of the battery is equal to or less than a second threshold value, or when the voltage value of the battery is less than the second threshold value which is lower than the first threshold value.

Abstract: A power supply control device for controlling power supply to a pair of terminals to which a load is connected, comprising a voltage measuring part for measuring a voltage which has a predetermined relationship with the voltage of the pair of terminals, a short circuit detecting part for detecting whether a short circuit exists between the pair of terminals based on the measured voltage and for making power supply to the pair of terminals stop when existence of a short circuit is detected, and a constant current supplying part for supplying a constant current though the pair of terminals; wherein the short circuit detecting part is configured to detect that the previously detected short circuit is eliminated when the voltage measured by the voltage measuring part is equal to or greater than a predetermined threshold value upon supplying the constant current through the pair of terminals.

Abstract: A primary circuit turns on switching elements and generates energy from a direct-current power supply to a secondary circuit through a transformer. The secondary circuit charges a driven element using the energy obtained from the primary circuit through the transformer, turns on a switching element, discharges the energy accumulated in the driven element, and generates the energy in the primary circuit through the transformer. The primary circuit returns the energy obtained from the secondary circuit to the direct-current power supply.

Abstract: An edgewise coil achieves positioning of both end portions and accurate and reliable conduction with respect to a circuit board in a simple configuration, and can be downsized. The edgewise coil is usable in a conductor. The edgewise coil includes a base material and a coil member fixed at both end portions to the base material and including an external wound-wire portion placed on the base material and an internal wound-wire portion extending in the base material.

Abstract: Even if a network setting changes due to power interruption or the like, communication for controlling the operating status of load devices of an uninterruptible power supply is enabled to continue. A network communication system (1) for the uninterruptible power supply comprises UPS member controllers (12 and 13) and a UPS group controller (11) which are connected in a network (2) to control the operating status of the load devices (3) of the uninterruptible power supply (1). The UPS group controller (11) and the UPS member controllers (12 and 13) execute data communication according to a predetermined communication protocol (Internet Protocol or the like) through the network (2), and these controllers transmit/receive data in which specific identification information issued for each of the UPS member controllers (12 and 13) is added to control data as communication data in the data communication according to the predetermined communication protocol.

Abstract: There is provided a digital controller which can reduce a variation in output voltage as compared to the conventional digital controller at the time of abrupt changes in load and in input of a power amplifier. The digital controller is built in the power amplifier for supplying an output voltage vo to a load and is equipped with a manipulated variable calculating unit which detects the output voltage vo to calculate a manipulated variable ?1 and a signal generating unit which converts the manipulated variable ?1 into a signal for making the power amplifier operate. A feedforward function from an equivalent disturbance qy caused by the variation in the load is replaced by a feedback function from the output voltage vo and the manipulated variable ?1, thereby allowing a transfer characteristic from the disturbance qy to the output voltage vo to result in a quadratic differential characteristic.

Abstract: An edgewise coil achieves positioning of both end portions and accurate and reliable conduction with respect to a circuit board in a simple configuration, and can be downsized. The edgewise coil is usable in a conductor. The edgewise coil includes a base material and a coil member fixed at both end portions to the base material and including an external wound-wire portion placed on the base material and an internal wound-wire portion extending in the base material.

Abstract: It is an object of the invention to provide a substrate which allows visual confirmation of the joint state and improvement of reliability of the joint between the components and the substrate to be mounted. The substrate is configured to mount a component having a planer terminal and include a land subjected to solder joint with respect to the terminal of the component. A substrate includes notched portions formed by notching parts of the lands in the direction away from an end surface forming the space. The each land on the substrate includes a first land formed on the substrate and a second land formed of an end surface of the notched portion in the direction of thickness of the substrate. Therefore, visibility of parts of terminals of components is secured utilizing penetration of the notched portions at the time of soldering, so that the joint state of soldering can be visually confirmed.

Abstract: A switching power supply device ensuring no voltage dip is caused by a sink current even if started with output voltage accumulated. When input voltage Vi is reapplied with output voltage Vo accumulated, supplying PWM signals to main switching element 9 and rectifying switching elements is stopped by output detection circuit 21 until a voltage produced by dividing output voltage Vo decreases to a first threshold allowable for energy caused by a sink current. Accordingly, inflow of the sink current immediately after reapplication of input voltage and the subsequent voltage dip are inhibited. Afterward, when the voltage produced by dividing the output voltage Vo decreases to the first threshold and then main switching element starts operating by PWM signal from control circuit 22, drive detection circuit 31 detects this condition to permit supplying PWM signal to rectifying switching elements 10, enabling inhibition of the subsequent inflow of the sink current.

Abstract: A discharge lamp lighting device capable of preventing magnetic saturation of an inductor connected with an output of an inverter. An inverter 12 comprises a first set of switching elements 32, 33 for switching an output voltage of the inverter 12 to a positive polarity and a second set of switching elements 31, 34 for switching the output voltage thereof to a negative polarity. At the start-up of a lamp 20, each of the switching elements 31 to 34 is allowed to perform switching operations in such a pattern that after turning on and off the first set of the switching elements 32, 33 more than once, the second set of switching elements 31, 34 are allowed to turn or and off more than once. Accordingly, energy stored in the inductor 37 is discharged during a temporary off-period, thus permitting the inductor 37 to be prevented from being magnetically saturated.