Compact-Size and High-Conversion-Efficiency Regulator for Alternating-Current-Operated Light-Emitting Diodes

A compact-size and high-conversion-efficiency regulator used to stabilize the luminous flux of alternating-current-operated light-emitting diodes (ACOLEDs) is proposed. The presented regulator is composed of a full-bridge rectifier and a power switch to supply directly from ac power source for the ACOLEDs without any ac/dc converter. Commonly adopted pulsewidth modulation techniques are utilized to regulate the input power fed into ACOLEDs. Design guidelines and experimental results of the prototyping regulator for an 8-W ACOLED operating under different input ac voltages (110 ±10 V_rms, 60 Hz) are provided. According to the experimental results, the advantages of the proposed regulator include simplified design, compact size, high conversion efficiency, and low cost. Since no magnetic component is required in the presented system, therefore, it can easily be fabricated into the same ACOLED chip in the future.