Patent ID: 8624520
Filing Date: 2014-01-07
Classification: G09G,H05B,Y02B

Abstract:
1. An electrical appliance comprising: a lighting device ( 8 ) having light emitting diodes ( 12 ) and a power supply unit ( 2 ), wherein the power supply unit ( 2 ) has a mains connection ( 7 ), a DC voltage/AC voltage converter ( 15 ) and a high-frequency transformer ( 16 ), wherein the lighting device has a current balancing network ( 17 ) for controlling the light emitting diodes ( 12 ) that is connected to the high-frequency transformer ( 16 ), the light emitting diodes ( 12 ) are collected in individual LED strings ( 11 ) and each of the LED strings ( 11 ) has at least one of the light emitting diodes ( 12 ), wherein each of the LED strings ( 11 ) is disposed in a circuit branch ( 19 ) of the current balancing network ( 17 ) and the circuit branches ( 19 ) are connected in parallel, wherein in each of the circuit branches ( 19 ), the LED string ( 11 ) is connected to an output of a bridge rectifier ( 20 ), one input pole of the bridge rectifier ( 20 ) is connected to the high-frequency transformer ( 16 ) and an other input pole of the bridge rectifier ( 20 ) is connected to a primary winding ( 22 ) of a balancing transformer ( 23 ) and a secondary winding ( 26 ) of the balancing transformer ( 23 ) is connected in series to secondary windings ( 26 ) of balancing transformers ( 23 ) in the parallel circuit branches ( 19 ) in a closed conductor loop ( 27 ), and a controlling device ( 33 ) having a signal receiver ( 34 ) by which the primary-side current supply of the power supply unit ( 2 ) is controllable using control lines ( 35 ).