| Patent Number |
Title Of Patent |
Date Issued |
| 7067994 |
Electronic ballast with overvoltage monitoring |
June 27, 2006 |
| An electronic ballast for at least one gas discharge lamp (LA), preferably for a fluorescent tube, having a rectifier circuit (2) connectable to a supply voltage source, a smoothing circuit (3) connected to the output of the rectifier circuit (2) for generating an intermediate circuit vo |
| 7057358 |
Electronic ballast and operating method for a gas discharge lamp |
June 6, 2006 |
| In an electronic ballast the output d.c. voltage (U) of a PFC intermediate circuit (3) is to be regulated. The intermediate circuit (3) has a clocked switch (S) which is controlled by a regulation circuit (7). The regulation circuit (7) includes two counters (Z1, Z2). The counter (Z1) |
| 6909246 |
Electronic ballast and electronic transformer |
June 21, 2005 |
| An electronic ballast which includes a resonant load circuit (L1, C1) in series with a discharge lamp (LA), the resonant load circuit being supplied by an inverter (S1, S2) which outputs variable alternating voltages at frequencies above 200 KHZ. Alternatively, an electronic transfor |
| 6876158 |
Electronic ballast with full bridge circuit |
April 5, 2005 |
| An electronic ballast for controlling the operating behavior and brightness of a gas discharge lamp, includes a full bridge circuit fed with a d.c. voltage (U.sub.BUS). The gas discharge lamp is connected as a load of the full bridge circuit, and a control circuit in each case switches o |
| 6826059 |
Drive for light-emitting diodes |
November 30, 2004 |
| A circuit and a method for controlling light emitting diodes (D1, D2) for illumination involve an inverter whose output frequency can be varied. The inverter includes two electronic switches (S1, S2) which convert an applied direct current voltage (U.sub.o) into an alternating voltage. A |
| 6765354 |
Circuitry arrangement for the operation of a plurality of gas discharge lamps |
July 20, 2004 |
| A circuitry arrangement for operating n gas discharge lamps, n being a whole number greater than 1, includes a single inverter, fed with d.c. voltage, for generating an a.c. voltage alterable in its frequency, delivered to a load circuit arranged at the inverter's output. The load ci |
| 6747423 |
Circuit configuration to operate a gas discharge lamp |
June 8, 2004 |
| In a circuit configuration to operate a gas discharge lamp (LA) the lamp (LA) is arranged in a full bridge circuit. A control circuit in normal operation actuates the four switches (S1-S4) in such a way that it changes over with a first frequency (f1) alternately between a first and a se |
| 6747420 |
Drive circuit for light-emitting diodes |
June 8, 2004 |
| The invention relates to a control circuit for at least one light-emitting diode (1) for adjusting the current and/or the voltage of the light-emitting diode (1) to a desired value adjusted by means of a controller (3), the current, the voltage and/or the luminescence of the light-em |
| 6577079 |
Electronic ballast with intermediate circuit regulation |
June 10, 2003 |
| An electronic ballast for at least one gas discharge lamp (LA) comprises a rectifier circuit (2) connectable to an a.c. voltage source (U.sub.0), a smoothing circuit (3), connected to the output of the rectifier circuit (2), for generating an intermediate circuit voltage (U.sub.z), and a |
