A Cfl Half-bridge Power Electronic Ballasts Drive Chip Design

High voltage IC and smart power IC are the main branches of power IC. It is the result of the combination of microelectronics and power electronics. HVIC makes it possible to fabricate high voltage devices and low voltage control circuit in one chip. It also makes power IC simpler and the price, weight and volume of power IC decrease. High voltage monolithic integrated circuit can be used in many fields, for example, telecommunication, remote control, display driver and automobile. New government energy-efficiency programs are further reshaping HVIC designs.The objective of this work is to design a half-bridge power IC for CFL lamps. The chip has characteristics of built-in RC oscillator circuit, power supply control circuit, driver circuit and two half-bridge power transistors, integrated low-voltage supply, integrated bootstrap diode. Also, the IC features a soft start function, an adjustable internal oscillator frequency and internal drive function with a high-voltage level shifter for driving the half-bridge. To guarantee an accurate 50% duty cycle, the oscillator signal is passed through a divider before being fed to the output drivers. The non-overlap time is defined as the time that both MOSFETs are not conducting.In this dissertation, the mode operations of the proposed ballast circuits are analyzed in accordance with the conducting conditions of the power switches. The equivalent resistance model of fluorescent lamp(CFL) is implemented to calculate the performances of the ballast-lamp circuit at steady-state. Also it introduces the fundamentals of electronic ballast, especially application theory and internal blocks of the chip. Then it presents the details of the circuit design and simulation results, including reference, oscillator, glow time control, pulse-generate, shifter, HS-driver and supply control. At last, the thesis introduces the layout of the transistors.