Design And Implementation Of LED Constant-current Driver Control Chip Based On Source Driver

With the continuous progress of technology,rapid development of the industry,as well as the continuous promotion and application of the semiconductor industry,the applications of Light-Emitting Diode(LED)continue to enrich human life.With the advantages of practicability,environmental protection,safety,long service life,low power consumption,less heat dissipation and high brightness,the new LED devices have been widely used in home lighting,road marking,indoor and outdoor decoration,background light source and other fields.Due to the driving characteristics of LED are different from the driving mode of traditional lighting equipment,it is very important for a LED equipment to design a good driver power.This paper aims to design and implement a LED driver power control chip based on BICMOS technology.The specific circuit design,layout design and chip packaging and testing are presented.The final test results show that the designed LED chip with non-isolated buck structure and source driver basically meets the design requirements,and can achieve a higher constant current precision with less peripheral devices.This paper first briefly investigates the basic concept and principle of LED,analyzes the classification and design elements of LED driver power,and the development status of LED lighting industry.Secondly,the design target and work parameters of the chip,the whole framework of the chip and the typical application circuit are given.On this basis,the specific design processes of sub circuit modules,including bandgap reference circuit,bias circuit,VCC clamp circuit,UVLO circuit,line voltage compensation circuit,OCP circuit,degaussing detection circuit,oscillator circuit,logic circuit,and LED short circuit protection circuit and OTP protection circuit,are given,the functions and parameters of each module are also analyzed,and the simulation results of each sub module and the whole chip are presented.Subsequently,this paper analyzes the production process characteristics of the chip and the structure of various types of devices,and fulfills the module design,layout of the overall layout design,the DRC verification,LVS verification,PEX and post simulation verification of the layout.Finally,the chip is packaged and the finished products are tested,including the startup circuit test,normal waveform test,output short circuit protection test,conversion efficiency test,line voltage regulation and load regulation test and the ESD chip test.The test results show that the designed chip reaches the predetermined target.