Abstract:

In this study, a driver system for high-power light-emitting diodes (LEDs) is presented. The proposed driver system is based on flyback converter topology, and it uses single-stage power factor correction with microcontroller support. The driver has two main parts; a source for an LED array, and a control unit including sensors. Instead of using conventional constant voltage or constant current driver topologies, the proposed system adjusts the output voltage by considering the LED parameters, the number of serial and parallel LEDs on the load array, and the data from sensors. Via the current sensor, the output current is measured at specific periods and limited by the microcontroller according to the LED load. Moreover, the microcontroller can detect an open circuit condition on the LED array by following current changes. A temperature sensor and a light-dependent resistor (LDR) are used to increase the lifetime of LEDs.

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