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This paper outlines the various driving and control techniques for Light Emitting Diodes (LEDs). LEDs should be driven from a constant current source. High power LEDs are usually driven from a switching regulator, for reasons of efficiency. The types of drivers described include Buck (step-down), Boost (step-up) and Buck-Boost (step-up or step-down). Isolated drivers and Power Factor Correction (PFC) circuits are also described. This brief paper can only describe the basic outline of these circuits, but this should be sufficient to allow the basic principles to be understood.

This paper presents the design and modeling of power electronic converters such as buck–boost and Ćuk operated under continuous conduction mode (CCM). The open-loop behavior of buck–boost and Ćuk converters needs modeling and simulation using modeled equations. The closed-loop control of these converters has a propositional–integral–derivative (PID) controller. PID controller parameters are obtained from Ziegler–Nichols step response method. These converters can be analyzed using the state equation. The MATLAB/SIMULINK tool is used for simulation of those state equations. Ćuk and buck–boost converters are designed and analyzed. The mathematical model of power Converter for simulation has been carried out using SIMULINK with/without any Sim Power System Elements. The open- and closed-loop results are compared.