Title :
An LED Drive Circuit with Constant-Output-Current Control and Constant-Luminance Control
Author :
Nishikawa, Masahiro ; Ishizuka, Yoichi ; Matsuo, Hirofumi ; Shigematsu, Kyohhei
Author_Institution :
Nagasaki Univ.
Abstract :
A single LED is very small, and their luminance is related to the amount of driving current. Sufficient luminance for an illuminator requires many LEDs to be connected together and a constant current supplied to each LED. Therefore, the LED drive circuit must have constant-output-current control and/or constant-luminance control. We propose an LED drive circuit that consists of a boost-type DC-DC converter with constant-output-current control and constant-luminance control. This circuit is a switching regulator-type circuit controlled by pulse width modulation (PWM). Both the power and the constant-current control can be provided by a single system, without any ballast resistor or auxiliary current control circuit
Keywords :
DC-DC power convertors; PWM power convertors; brightness; driver circuits; electric current control; light emitting diodes; optical variables control; power control; switching convertors; LED drive circuit; PWM control; boost-type DC-DC converter; constant-luminance control; constant-output-current control; power control; pulse width modulation control; switching regulator-type circuit; Control systems; Current supplies; DC-DC power converters; Electronic ballasts; Light emitting diodes; Pulse circuits; Pulse width modulation; Resistors; Space vector pulse width modulation; Switching circuits;
Conference_Titel :
Telecommunications Energy Conference, 2006. INTELEC '06. 28th Annual International
Conference_Location :
Providence, RI
Print_ISBN :
1-4244-0430-4
Electronic_ISBN :
1-4244-0431-2
DOI :
10.1109/INTLEC.2006.251597
