Design of a high power LED constant current driver

In this paper, a high power LED constant current drive circuit based on BUCK circuit is designed. The circuit has the characteristics of wide input voltage range (6V~42V), high efficiency, high integration, high reliability, small volume and so on. Inside the circuit integrated 1.5A power PMOS; In order to improve the reliability of the system, the circuit is integrated with LDO module, bias current module, digital dimmer module, overtemperature protection module, logic control module and driver module. Through Cadence software for basic circuit module and system parameters of the simulation and optimization, the results show that the control circuit based on conduction time control mode to achieve the high precision, and has a wide range of input voltage, low voltage reference source and PWM dimming function, such as driving current can be up to 1.5 A, and no compensation will be able to steady work.