LED Permanent Emergency Lighting System Based on a Single Magnetic Component

The use of high-efficiency LEDs in low-power lighting applications is growing continuously due to new advances in LED features. The lifetime of a low-power fluorescent lamp is around 5000 h. This implies short lamp-replacement times and high maintenance costs. The use of high-efficiency LEDs reduces drastically the maintenance costs due to the long lifetime (>50 000 h). One of the applications where using LED is very interesting is permanent emergency light systems. Generally, these circuits are based on a two-stage design, using two magnetic cores. This paper presents offline power LED driver and battery charger integrated in one magnetic core topology. Besides, the converter allows driving the LEDs in case of a line failure and it complies with the IEC 61000-3-2 Class C Standard.