Abstract: The control circuit comprises a source of dc voltage, a first electronic switch, interposed between a first terminal of the voltage source and a corresponding first terminal of the load, a second electronic switch, interposed between the other or second terminal of the load and the other or second terminal of the source, a current recirculation device, including a diode connected between the said first terminal of the load and the other or second terminal of the voltage source to allow a circulation current in the load when the first switch is open, and a control circuit arranged to control the switches in a predetermined manner. The recirculation device further includes a third electronic switch disposed between the first terminal of the load and the other or second terminal of the voltage source, and the control unit is arranged to control this third switch in a synchronous manner, but in phase opposition, in relation to the first switch.

Abstract: The invention finds application in the field of power supplies for valve actuators, and particularly relates to a wide voltage range stabilized switching power supply for valve actuators, of the type that comprises a filter 2, a diode bridge 3, an array of capacitors 5, an auxiliary power supply stage 6, formed by a switch mode circuit, having an operating range of 21 to 380 VDC, which generates the supply voltages required for the internal operation of the power supply, a full-bridge power stage 7, which receives an input voltage in the range of 120 VDC to 373 VDC, and generates the three stabilized output voltages required for supplying the load, and a boost stage 4, located upstream from the power stage 7, which allows to increase the voltage to a value in the range of 120 VDC to 373 VCC, whenever it is below such range.

Abstract: System and method for protecting an integrated circuit. The system includes a first transistor coupled to a first voltage and a second voltage, a second transistor coupled to the gate of the first transistor and the first voltage, a third transistor coupled to the gate of the second transistor and the first voltage, and a capacitor coupled to the gate of the second transistor and the second voltage. The first voltage is provided to the integrated circuit, the gate of the third transistor is configured to receive a first control signal, the gate of the second transistor is configured to receive a second control signal, and the second control signal is capable of turning off the second transistor a time period after the third transistor is turned off.

Abstract: An ESD protection circuit for an input/output pad of an IC is disclosed with discharge paths to both a power rail and ground. The ESD circuit is arranged with NMOS and PMOS transistors arranged with their drains connected to the pad. However, the drain capacitances have voltage sensitivities that compensate or cancel each other, and with proper sizing the capacitance load on the pad can be made substantially constant over a given voltage range. By providing a discharge path to a power rail, the ESD circuit may be designed to be more tolerant of overvoltages on the power rail.

Abstract: A current sensing transformer having a low impedance primary winding is connected in series with a filter and load circuit supplied with output current by a high frequency switching PWM power supply such as a sinewave dimmer. Sensed output current is supplied to a microprocessor based programmable controller. The controller performs a routine including a family of overcurrent tests. Tests of the family are satisfied by the presence of different output current values for different time durations. At least one of the tests is enabled only at low requested output voltages or dimming levels. In response to satisfaction of any of the tests, a series power switching stage of the power supply is rendered nonconductive to shut down the power supply.

Abstract: The invention concerns an electrical circuit for limiting the switching-on current through a load during a switching-on process, comprising an electrical component which is connected in series to the load. To ensure current limitation which is independent of the load and of the value of the supply voltage, and simultaneously to avoid switching current peaks and minimize dissipated heat, the current-limiting component is in the form of an active component which has an internal resistance, and which is controlled by a timing element in such a way that the internal resistance of the component is reduced during a switching-on process.

Abstract: A three-phase filter has first, second, and third power source connectors and first, second, and third load connectors. A separate phase line filter is connected between each pair of power source and load connectors. Each phase line filter includes a line winding connected between the power source and load connectors for a phase line and includes a first shunt winding, resistor and capacitor connected in series between that load connector and the load connector for another phase line. The line and shunt windings for a given phase line filter are wound on a core in directions so that one winding produces magnetic flux having an opposite polarity to the magnetic flux produced by the other winding. The magnetic coupling of those windings, mitigates harmonic currents that otherwise flow in either direction between the power source and load connectors.

Abstract: A three-terminal snapback device is utilized with a control circuit to provide a low snapback voltage that is protected from non-ESD voltage spikes and ripples. In response to a fast edge, the control circuit lowers the snapback voltage, unless a status signal indicates that normal operating voltages are present, and raises the snapback voltage a predefined time later. If the fast edge represents an ESD pulse, SCR operation is initiated at the lowered snapback voltage. If the fast edge represents a power on sequence, the maximum voltage is less than the momentarily lowered snapback voltage and therefore insufficient to initiate SCR operation. Further, once normal operating voltages are present, the control circuit continuously maintains the raised snapback voltage so that a non-ESD voltage spike or ripple can not improperly turn on the snapback device.

Abstract: An apparatus is disclosed that drives an inductive load according to a control signal from an external controller transmits temperature data to it for indicating a condition of the inductive load through a line driver. The external controller regenerates the control signal according to the temperature data. According to the control signal, the apparatus operates a pair of power supply circuits to complementarily supply power to the load. Thermal conditions of the power supply circuits and the line driver are monitored for detecting an overheat condition. The transmission of temperature data to the external controller is enabled as long as no overheat condition is detected in both of the power supply circuits and line driver. If an overheat condition is detected in at least one of the power supply circuits and line driver, heat protection is performed and the overheat condition is communicated to the external controller.

Abstract: A control circuit (1) includes two input terminals (2, 3) for respectively electrically connecting with the active and neutral conductors (4, 5) of a mains power source (6). Two output terminals (7, 8) electrically connect with a load in the form of a two pin domestic electrical appliance (9). Conductors (4, 5) terminate at a domestic power outlet socket, and terminals (7, 8) are incorporated into a two pin plug for insertion into that socket. That is, terminals (7, 8) include elongate bundled conductors for extending between the outlet socket and the circuit. Appliance (9) has a conductive component, in this instance a housing (10) that, under normal operating conditions, is electrically insulated or otherwise electrically isolated from conductors (4, 5). The housing provides a reference point for circuit (1), and is electrically connected to that circuit by way of a conductor (11).

Abstract: The present invention is a method and system for providing improved isolation for power supplies while minimizing power dissipation. A body diode of a MOSFET may be utilized with a comparator circuit. The comparator circuit may detect current flow across the MOSFET and may turn the MOSFET on. This may shunt the diode with a low drain to source resistance limiting power dissipation across the diode to an amount of the drain to source current squared (Ids2) times the drain to source resistance of the MOSFET when on (RDSon). Use of the comparator circuitry may reduce the time delay associated with turning the MOSFET off to prevent a high reverse inrush current within a power supply.

Abstract: A self-excited DC-DC converter comprises a switching element that chops a direct-current input voltage; a smoothing circuit that smoothes the chopped voltage to generate a DC output voltage; a switching control signal generation circuit that generates a switching control signal for the on/off control of the switching element by comparing a feedback voltage of the output voltage and a comparison voltage; an output correction circuit that adjusts the comparison voltage according to an error between the feedback voltage and the reference voltage and, when the output current is in the overcurrent state, reduces the level of the comparison voltage; an overcurrent protection signal generation circuit that, when the output current is in an overcurrent state, generates an overcurrent protection signal for turning off the switching element regardless of the switching control signal; and a delay circuit that delays the overcurrent protection signal. Also, a switching control circuit is provided therein.

Abstract: A panel is provided on a front side of an electronic device. A driving unit opens and closes the panel. A position detecting unit detects whether the panel is open. An object detecting unit detects whether there is an object on the panel when the panel is open. A control unit controls the driving unit not to close the panel when there is an object on the panel.

Abstract: A method and apparatus for dechucking a substrate is provided. In one embodiment, a processing chamber is provided that includes a grounded chamber body having a substrate support assembly disposed in an interior volume. A dechucking circuit selectively couples the substrate support assembly to ground or to a power source. In another embodiment of the invention, a method for dechucking a substrate includes the steps of completing a plasma process on a substrate disposed on a grounded substrate support assembly, disconnecting the substrate support assembly from ground, and applying a dechucking voltage to the substrate support assembly.

Abstract: An electric circuit for capacitive sensor elements of a touch switch can be designed as a switch capacitor circuit and van be provided with a micro controller. The sensor elements are provided in sensor branches with a charging capacitor. In addition, a reference branch is provide. It contains a reference capacity and a reference charging capacitor, which have capacities that correspond to those of the sensor branches. By comparing the number of charge transfer processes required to reach the switching threshold in the sensor branch and the reference branch, fluctuations of the supply voltage, and consequently the switching threshold itself, can be compensated for.

Abstract: A method and apparatus control a power converter (20) of a motor drive system. The power converter (20) is controlled during a first operating mode by applying a current control scheme, which sets power converter commands to control active and reactive current components flowing from the power converter (20) to the motor (30) to achieve desired motor speed; and a fault protection scheme is executed during a second operating mode. The fault protection scheme generates power converter commands to reduce the active current component flowing from the power converter (20) to the motor (30) is substantially zero. The first operating mode will be resumed upon receiving the restart command if the motor speed is above a pre-set shutdown threshold.

Abstract: In a plasma reactor having an electrostatic chuck, wafer voltage is determined from RF measurements at the bias input using previously determined constants based upon transmission line properties of the bias input, and this wafer voltage is used to accurately control the DC wafer clamping voltage.

Abstract: A vehicle electronic key system that may be lent to a third person without having to worry about how the key would be used. The key system includes a portable key and a control unit installed in a vehicle. When the vehicle owner does not want the third person to use a certain accessory, the owner registers a restriction code in the key. The restriction code is registered only when a fingerprint input from an input device matches the owner's fingerprint that is pre-registered in the key. The registration of the restriction code prohibits operation of the accessory.

Abstract: A universal interface circuit and an associated method are provided that can supply a computer logic circuit, such as the components mounted upon an adapter card, with first and second inputs having first and second predetermined voltage levels, respectively, based upon power drawn from both first and second supply voltages. The interface circuit typically includes a first power supply circuit for providing the first input having the first predetermined voltage level in response to the first supply voltage. Additionally, the interface surface includes a regulator for generating an output having the second predetermined voltage level in response to the first supply voltage. The interface circuit further includes a second power supply circuit for providing an output that also has the second predetermined voltage level, albeit in response to the second supply voltage.

Abstract: A tri-phase surge protector comprises a first zinc oxide ceramic body; a first electrode layer on a surface of the first zinc oxide ceramic body and having a first electrode, and the first electrode includes a first terminal; a second electrode layer on another surface of the first zinc oxide ceramic body; a second zinc oxide ceramic body on the second electrode layer; a third electrode layer on another surface of the second zinc oxide ceramic body and having a second electrode, and the second electrode includes a second terminal; a third zinc oxide ceramic body on the second electrode layer and at the second zinc oxide ceramic body; and a fourth electrode layer on another surface of the third zinc oxide ceramic body and having a third electrode, and the third electrode includes a third terminal. The invention also discloses a method for manufacturing a tri-phase surge protector.