METHOD OF CONTROLLING SUPPLY SOURCE VOLTAGE, AND MULTI-CHANNEL LIGHT-EMITTING DIODE DRIVING CIRCUIT AND MULTI-CHANNEL SYSTEM USING THE SAME

摘要

PPROBLEM TO BE SOLVED: To provide a multi-channel light-emitting diode (LED) driving circuit that supplies voltages optimized for respective channels each including an LED string formed by coupling a plurality of LEDs in series. PSOLUTION: The multi-channel LED driving circuit includes an LED array, a DC-DC converter, and a dynamic room control block, wherein the LED array includes N LED channels each having a plurality of LEDs connected in series. The DC-DC converter generates a supply source voltage corresponding to a second reference voltage. The dynamic room control block compares channel voltages of common nodes of the N LED channels and the current drivers with combination voltages of a first reference voltage and a hysteresis voltage, and generates a second reference voltage in response to at least one dimming signal that defines a time period during which a predetermined current flows to the current drivers through the N LED channels. PCOPYRIGHT: (C)2011,JPO&INPIT