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.

fYear

2006

fDate

Sept. 2006

Firstpage

1

Lastpage

6

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;

fLanguage

English

Publisher

ieee

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

Type

conf

DOI

10.1109/INTLEC.2006.251597

Filename

4018099