| The energy crisis, caused by rapid economic development, brings about the use of energy conservation technology as the government and people's hot topic. The semiconductor lighting LED with high efficiency, energy conservation, environmental protection, long-lifetime, easy maintenance, is expected to become a new lighting source after the incandescent lamp and fluorescent lamp. Its average annual growth rate of the global market is more than 20%. Our national Semiconductor lighting project was in full swing in 2003. White LED has entered the illumination market with the support of the government, and will promote comprehensively during "11.5" plan. The research of white-LED driving chip has great practical significance.This lighting driving chip in this thesis belongs to boost charge pump type. The chip is fabricated in 0.6μm standard CMOS process. It makes possible the compatible integration of clock-control,charge pump,constant current driver and power device with conventional CMOS signal processing circuit. It can work in low voltage supply (2.4V),and can drives a semiconductor light working under 3.5V DC voltage and 100mA DC current, with constant current despite of changes in voltage supply or temperature. The key problem of the design is the reasonable choice of charge pump's operating frequency, MOSFET switches' W/L, transmission capacitance, the timing control.This paper comprises five chapters. Chapter â… is briefed on the development and driven approach of white LED; Chapter â…¡ says the charge pump's types and operating principles; Chapter â…¢ is expounded the circuit design of this chip; Chapter â…£ will introduce the chip test and its characteristic analysis; Chapter â…¤ is the summary and some improvements vision.The current research on LED driver with charge pump is in close connection with the development of market dynamics, and can drive for miner's lamp, flashlight, reading lamp. Its design principles can also be used to promote to higher power led driven.
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