The Driver Chip Design Of CFL

High voltage IC and smart power IC are the main branchs 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.It can be used in many fields,such as telecommunication,remote control,display driver and automobile.As the environmental awareness has been enhanced,goverment's energy-efficiency requirements are getting higher.And this promotes the future development of HVIC design.The objective of this work is to design a half-bridge power driver IC for CFL lamps.The major function of this chip is to realize a DC-AC reverse of half-bridge which can start up the CFL and matain it lighting. The chip has characteristics of low voltag power supply,built-in RC oscillator circuit, control circuit,driver circuit and two half-bridge power transistors.And the IC features a soft start function,a bootstrap fuction,an adjustable internal oscillator frequency,dead time function,a accurate 50% duty cycle control and internal drive function with a high-voltage level shifter for driving the half-bridge.In this dissertation,the properties of CFL,and fundamentals of electrical ballast are analyzed carefully.The principle of half-bridge architecture have been studyed intensively according to the equivalent model of fluorescent lamp. Also the application theory and internal blocks of the chip are introduced.Then details of the circuit design and simulation results are presented,including LDO,POR,Bandgap reference,oscillator, Frequncy-sweep, shifter, non-overlap control, driver.Besides,the fundamentals and layout of the devices are displayed.Finally the testing results of the chip are introduced.