Patent ID: 7253564
Filing Date: 2007-08-07
Classification: H05B

Abstract:
1. A lamp current balancing device comprises: an electronic power switch, a transformer, a current transformer and a pulse width modulation (PWM) IC; the transformer having a primary side connected to the electronic power switch and both ends of a secondary side connected to one end of each one of two lamps respectively, with another end of each one of two lamps connecting to one end of a primary side of the current transformer respectively, the PWM IC being coupled between a secondary side of the current transformer and the electronic power switch; the current transformer detecting an operating current of the two lamps and feeding back the operating current to the PWM IC, the PWM IC receiving and processing the operating current to obtain a control signal, then outputting the control signal to the electronic power switch to control a pulse width outputted by the electronic power switch, thereby controlling and maintaining a uniform brightness of the lamps.