Integrated Lighting Unit with Regulated Pulse Current

• Main Authors: Ming-Shian Lin, 林明憲
• Other Authors: Chern-Lin Chen
• Format: Others
• Language: en_US
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/00936841798014954376

博士 === 國立臺灣大學 === 電子工程學研究所 === 101 === This dissertation presents an integrated lighting unit with regulated pulse current for low-power application. A white LED with a regulated pulse current driver integrated in one chip, which is named a lighting unit in this dissertation. Such a combination reduces the packaging costs and the size of the device as well as increases the luminous density. In addition, as the pulse current is directly driven without passing through multiple packages, the parasitic effects can be greatly reduced. Based on previous literatures and the relative theory, we develop a lighting unit by bonding the LED and its driver with a wire interconnection and with vertical stack integration architecture to achieve better luminous efficacy and lower junction temperature. The white LED is synthesized by a blue LED with yellow phosphor and this driver is fabricated with 0.5μm CMOS process. Two control signals are used in the proposed driver to modulate the pulse current. One signal modulates the amplitude of pulse current and the other modulates the pulse current frequency. The proposed driver only needs a sensing resistor for a closed loop without other compensation capacitors for stability consideration. This lighting unit has several advantages, such as compact size, low power consumption, high reliability and long lifetime. Therefore, it is suitable for portable application. In this dissertation, the basic operating principles of the regulated pulse current driver are described in detail, along with some experimental results to verify the feasibility of the proposed scheme.