Review of Dimming Techniques for Solid-State LED Lights

LEDs lights have numerous advantages as compared to conventional lighting sources and are becoming popular these days. Depending upon the application requirement brightness of the LEDs needs to be controlled. The brightness is controlled by controlling the forward current flowing through the LED. In this paper, different techniques used for dimming the brightness of LED lamps are reviewed. DC-DC SEPIC converter which is a fourth-order converter is used as driver to compare different techniques. Modeling of the SEPIC converter with LED modeled as resistive load is also presented. It is showed that PWM and pulse current techniques exhibits better dimming as compared to other dimming techniques discussed in this paper. Pulse current driving technique is the extension of the PWM technique. In order to verify the performance of dimming techniques simulation are carried out in MATLAB/SIMULINK environment.