LIGHT SOURCE CIRCUIT, BALANCED TRANSFORMER CIRCUIT, LIGHT EMITTING PANEL, AND CONTROLLING METHOD OF BALANCED CURRENT

摘要

PROBLEM TO BE SOLVED: To provide a controlling method of a balanced current serving for cost efficiency and regulating electric current of a color LED of each group in a light source of a backlight in such a manner as to effectively balance them, and provide a device including a light source circuit.

SOLUTION: A light source circuit supplies an electric current by using a plurality of transformers and drives a plurality of LEDs connected with a plurality of current paths. Each transformer has one current supply coil and one induction coil each having the turn ratio of the coils. The turn ratio of the coil is obtained on the basis of each of the turn ratios of the current supply coil and the induction coil. The current supply coil is used to provide output currents to different current paths, and the induction coil is connected with the induction coil of the other transformer to form a current loop. The relationship of the output current of each transformer and the other transformer is determined by turn ratios of the coils of the transformers connected with each other. The luminance of each LED is determined by the current of the current path.

COPYRIGHT: (C)2007,JPO&INPIT