Patent application number | Description | Published |
20080211423 | Multiple-Light Discharge Lamp Lighting Device - To provide a multiple-light discharge lamp lighting device that stabilizes and equalizes tube current of a plurality of discharge lamps without arranging a Ballast element to the secondary side of an inverter transformer with low costs. A multiple-light discharge lamp lighting device | 09-04-2008 |
20090051298 | Multiple discharge lamp lighting device - A multiple discharge lamp lighting device in which lamp current of discharge lamps is equalized by using a circuit structure having transformers on both sides of the discharge lamps and in which the number of parts can be reduced. A multiple discharge lamp lighting device | 02-26-2009 |
20090160349 | Electronic stabilizer circuit for suppressing startup instabilities in cold cathode fluorescent lamps - According to the present invention an electronic stabilizer circuit for suppressing startup instabilities when supplying a cold cathode fluorescent lamp with current is proposed which is connected in series with a power supply line of the cold cathode fluorescent lamp. The stabilizer circuit has variable impedance which is automatically adjusted depending on the magnitude of the lamp current thus limiting the lamp current to a certain current threshold. | 06-25-2009 |
20090184661 | Electronic circuit for operating a plurality of gas discharge lamps across a common voltage source - The proposed circuit makes it possible to operate a plurality of gas discharge lamps, particularly cold cathode tubes, across a common voltage source. The circuit reduces the resistance tolerance of the lamp characteristic curves through controlled debalancing of the lamp currents with the aid of debalancing modules. Through the active reduction in the resistance tolerance, the requirements placed on the electric strength of the balancing transistors as well as energy losses of the balancing circuit are reduced. | 07-23-2009 |
20090322249 | METHOD FOR CONTROLLING A HIGH-FREQUENCY TRANSFORMER - A method for controlling a high-frequency transformer by which the acoustic transformer noises occurring during intermittent operation (burst operation) are reduced. This is achieved according to the invention by halving a length of the first and the last pulse of an AC voltage pulse train or the first and the last half-wave in the ON interval (Tn). This goes to avoid magnetizing peaks in the core that cause a major part of the background noise. | 12-31-2009 |
20100327771 | METHOD FOR CONTROLLING GAS DISCHARGE LAMPS - The invention relates to a method and a device for controlling gas discharge lamps using a direct current/alternating current inverter (DC/AC inverter) that is operated at a predetermined frequency and that generates an AC output voltage U for operating the gas discharge lamps from a DC input voltage which has a residual ripple. According to the invention, the DC/AC inverter is operated in zero voltage switching (ZVS) mode, wherein the DC input voltage is used as the control variable for the lamp current I | 12-30-2010 |
20110266964 | ELECTRICAL APPLIANCE HAVING A LIGHTING DEVICE HAVING LIGHT EMITTING DIODES - An electrical appliance, particularly a television or a monitor, having a lighting device ( | 11-03-2011 |
20120281435 | DC-DC CONVERTER - A DC-DC converter ( | 11-08-2012 |
20130094250 | DOWN CONVERTER - A down converter for converting an input DC voltage (Vin) into a lower output DC voltage (Vout). The down converter has on the primary side ( | 04-18-2013 |
20130293125 | Control Circuit For LED Backlighting - The invention describes a control circuit for backlighting having a plurality of control channels in each of which a light emitting diode string is controlled. The control circuit has a balancing device for balancing the currents in the individual control channels, and a control unit that is connected to a power factor correction circuit (PFC), to a bridge circuit and to a primary-side current measuring device. Each control channel has a switch for switching the light emitting diode string that is connected to a separate dimming signal. The control circuit furthermore has at least one smoothing capacitor and one current limiter that limits the charging current for the smoothing capacitor. The control unit is additionally designed such that if all the dimming signals are logical ON, the output voltage of the PFC is regulated with the aid of the current measuring device such that the current on the primary side corresponds to a pre-determined setpoint value and that as soon as at least one dimming signal is logical OFF, the output voltage of the PFC is kept constant at its last value (FIG. | 11-07-2013 |