Design Of A High-power LED Drive Chip Based On CMOS Technology

As a fourth-generation high-power LED light source to replace the traditional electric lighting has become a major trend. As an important supporting industries of semiconductor lighting industry, high-power LED driver control circuit also attracted the attention of the industry.This paper designed a high-power LED driver controller based on CMOS technology. The main design targets of the chip are as follows: When the input voltage is 5 V, the average output current is stabilized at 350mA. When the input voltage range is from 4.5V to 5.5V and the tempreture range is from 0℃to 100℃, the fluctuation of average output current is less than 5%.The core circuits of the high-power LED drive controller includes current source bias ciruit,reference source,error amplifier,triangle-wave generator,In-phase amplifier,filter circuit,comparator and control circuit. These core circuits constituite a negative feed back part of the circuit structure to achieve the fuctuion that output is a constant current. In order to ensure the circuit to work, the paper also recommended a peripheral circuits of the chip(including the sample resistance and power management). According to demand, we can change the ratio relationship of width and length of the power switch in the external circuit to achieve a different output constant current.Based on CSMC's 0.5μm techonology, use Cadence software and Hspice software to implemente the circuit design and simulation. Use Mentor tools IC Station and Calibre to design and authenticate the layout. Simulation results show that the output PWM signal of the driver controller chip is achieved and the output current is constant equalt to 350mA. Finally the paper also provides a test program for the chip.