Conference

LED driver for automotive exterior lighting application
Romeo Letor, STMicroelectronics, China
Donato Tagliavia, STMicroelectronics, China
Luc Dang, STMicroelectronics, China

New automotive front light systems using high brightness white LEDS requires dedicated LED drivers. LED characteristics, driving methodology, low consumption, low emission, fault tolerance, diagnostics and compatibility with existing automotive body controllers are the main topics concerned. This paper illustrates system solutions with a new LED driver designed on purpose.

Dual-Mode Buck Control Circuit with Constant Power Regulation for HID Electronic Ballasts
Hongying Ding, International Rectifier, United States of America
Tom Ribarich, International Rectifier, United States of America

High-intensity discharge (HID) lamps have excellent characteristics with high efficacy, good color rendering and long lifetime. Electronic ballasts are used to control HID lamps but are typically complex due to the extensive lamp requirements they must fulfill. This paper describes a novel dual-mode buck circuit used to control HID lamps. This paper introduces the designer to the basic HID lamp requirements, presents the complete electronic HID ballast topology, describes the new buck circuit dual-mode control method, and provides the control circuit schematic with experimental results. HID lamps have unique electrical characteristics and require a careful and specific control solution. A fundamental understanding of these items will help the designer gain further insight to the nature of HID lamps and the circuits used to control them.

14:00

Design and Implementation of high efficiency power structures for LED street lights
Albert Chen, Fairchild Semiconductor, China
Charlie Wang, Fairchild Semiconductor, China
Bell Zhong, Fairchild Semiconductor, China
Jason Sun, Fairchild Semiconductor, China

This paper will explore the history and developments in LED street light applications and the role of power supplies in these applications. It will examine the methods for improving efficiency from a design standpoint and how this is implemented in actual street light applications. It will also delve into the structure and design of LLC resonant converters and demonstrate experimental results showing efficiency improvements through innovative semiconductor solutions and design.