Citation :

Dzhunusbekov Erlan, Orazbayev Sagi, "An Improved Hybrid LED Driver," International Journal of Engineering Trends and Technology (IJETT), vol. 74, no. 2, pp. 113-124, 2026. Crossref, https://doi.org/10.14445/22315381/IJETT-V74I2P108

Abstract

The continuous improvement of solid-state lighting technologies demands efficient and reliable LED drivers capable of minimizing switching losses while maintaining high power quality. Even a slight improvement in efficiency can have a significant economic impact, given the widespread adoption of LED lighting. This paper presents an experimental investigation of an improved hybrid LED driver that combines dynamic LED string reconfiguration with a low-power auxiliary switching stage to enhance efficiency. The proposed architecture employs protective diodes connected in series with MOSFETs, which effectively reduce switching stress without introducing significant conduction losses. A 200 W laboratory prototype with five LED strings was developed and tested under input voltages of 160-270 Vac at 50 Hz. Simulation and experimental results demonstrate good agreement, confirming the theoretical predictions. The prototype achieved a peak efficiency of 98.6% at 230 VAC, with a power factor of 0.98 and a total harmonic distortion of 11%. The experimental study confirms the practical feasibility and relative simplicity of the proposed improved hybrid driver. The switching transients and voltage stresses on transistors and diodes were significantly reduced. Low switching losses and the limited conduction losses of the protection diodes make it feasible to achieve future monolithic integration, combining not only the power transistors and control circuitry but also the protection diodes within a single chip.

Keywords

Capacitorless LED driver, Direct AC LED module, Hybrid LED driver, High voltage LED driver, LED street lighting.

References

[1] Osram, Reliability and Lifetime of LEDs Appication Note, 2013. [Online]. Available: https://www.osram.com/Graphics/XPic6/00102625_0.pdf

[2]     [2] Hui Zhang, “Reliability and Lifetime Prediction of LED Drivers,” 2017 14^th China International Forum on Solid State Lighting: International Forum on Wide Bandgap Semiconductors China (SSLChina: IFWS), Beijing, China, pp. 24-27, 2017.
       [CrossRef] [Google Scholar] [Publisher Link]

[3] Xiaohui Qu et al., “A Lifetime Prediction Method for LEDs Considering Real Mission Profiles,” IEEE Transactions on Power Electronics, vol. 32, no. 11, pp. 8718-8727, 2016.
[CrossRef] [Google Scholar] [Publisher Link]

[4] Murat Demir, Ali Bekir Yildiz, and Tayfun Ağir, “Observation of the Effects of Electrostatic Discharge and Lightning Surge on the Reliability of a LED Circuit Driven by Half-Bridge Converter,” 2018 International Symposium on Power Electronics, Electrical Drives, Automation and Motion (SPEEDAM), Amalfi, Italy, pp. 1073-1078, 2018.
[CrossRef] [Google Scholar] [Publisher Link]

[5] P. Watté et al., “Reliability of Electronic Drivers: An Industrial Approach,” 2021 18^th China International Forum on Solid State Lighting & 2021 7^th International Forum on Wide Bandgap Semiconductors (SSLChina: IFWS), Shenzhen, China, pp. 246-249, 2021.
[CrossRef] [Google Scholar] [Publisher Link]

[6] A.P. Sachintha, and G. De Vas Gunawardena et al., “LED Driver Useful Life: New Research on Multiple Component Degradation and Their Effects on Driver Life,” Lighting Design+ Application, vol. 53, no. 5, pp. 56-58, 2023.
[CrossRef] [Google Scholar] [Publisher Link]

[7] H. Niu et al., “Lifetime Prediction of Aluminum Electrolytic Capacitors in LED Drivers Considering Parameter Shifts,” Microelectronics Reliability, vol. 88-90, pp. 453-457, 2018.
[CrossRef] [Google Scholar] [Publisher Link]

[8] Bo Liu et al., “Consistency and Degradation of Electrochemical Double Layer Capacitors under Calendar Ageing,” 2020 Global Reliability and Prognostics and Health Management (PHM-Shanghai), Shanghai, China, pp. 1-5, 2020.
[CrossRef] [Google Scholar] [Publisher Link]

[9] K.I. Hwu, and W.C. Tu, “Controllable and Dimmable AC LED Driver Based on FPGA to Achieve High PF and Low THD,” IEEE Transactions on Industrial Informatics, vol. 9, no. 3, pp. 1330-1342, 2013.
[CrossRef] [Google Scholar] [Publisher Link]

[10] Yutsung Yeh et al., “AC Direct Multiple-String LED Driver with Low THD and Minimum Components,” 2015 International SoC Design Conference (ISOCC), Gyeongju, Korea (South), pp. 117-118, 2015.
[CrossRef] [Google Scholar] [Publisher Link]

[11] Hongbo Gao et al., “An Electrolytic-Capacitorless and Inductorless AC Direct LED Driver with Power Compensation,” 2015 IEEE 2^nd International Future Energy Electronics Conference (IFEEC), Taipei, pp. 1-5, 2015.
[CrossRef] [Google Scholar] [Publisher Link]

        [12] Hui Zhang, “Developing Highly Reliable LED Luminaries for High Temperature Applications using AC-Direct Driving LED Technology,” 2018 IEEE Applied Power Electronics Conference and Exposition (APEC), San Antonio, TX, USA, pp. 3466- 3470, 2018.
        [CrossRef] [Google Scholar] [Publisher Link]

        [13] Yuichi Noge, “Experimental Verification of a Linear AC LED Driver with a Light Flicker Compensating Circuit and High Power Factor Operation by Modulating the Current Regulator,” IEEJ Transactions on Industry Applications, vol. 139, no. 9, pp. 814-821, 2019.
        [CrossRef] [Google Scholar] [Publisher Link]

[14] Seong Jin Yun, Yong Ki Yun, and Yong Sin Kim, “A Low Flicker TRIAC Dimmable Direct AC LED Driver for Always-on LED Arrays,” IEEE Access, vol. 8, pp. 198925-198934, 2020.
[CrossRef] [Google Scholar] [Publisher Link]

[15] San-Fu Wang et al., “Ultra-Low Percentage Flicker High-Efficiency Direct AC LED Driver using Constant Power Technology,” IEEE Access, vol. 11, pp. 97400-97407, 2023.
[CrossRef] [Google Scholar] [Publisher Link]

[16] Hsiao-Hsing Chou, “Design and Implementation of the Linear LED Driver,” IEEE Transactions on Circuits and Systems II: Express Briefs, vol. 70, no. 3, pp. 1059-1063, 2023.
[CrossRef] [Google Scholar] [Publisher Link]

[17] Lisong Li, Yuan Gao, and Philip K.T. Mok, “A Multiple-String Hybrid LED Driver with 97% Power Efficiency and 0.996 Power Factor,” 2016 IEEE Symposium on VLSI Technology, Honolulu, HI, USA, pp. 1-2, 2016.
[CrossRef] [Google Scholar] [Publisher Link]

[18] Yuan Gao et al., “A Hybrid LED Driver With Improved Efficiency,” IEEE Journal of Solid-State Circuits, vol. 55, no. 8, pp. 2129-2139, 2020.
[CrossRef] [Google Scholar] [Publisher Link]

[19] Kwun-Hok Chong, Yuan Gao, and Philip K.T. Mok, “A Customized AC Hybrid LED Driver With Flicker Reduction for High Nominal Range Applications,” IEEE Transactions on Circuits and Systems II: Express Briefs, vol. 68, no. 5, pp. 1635-1639, 2021.
[CrossRef] [Google Scholar] [Publisher Link]

[20] ON Semiconductor, Power Factor Correction (PFC) Handbook, Application Note HBD853/D, 2014. [Online]. Available: https://www.onsemi.com/pub/collateral/hbd853-d.pdf

[21] Sam Abdel-Rahman, Franz Stückler, and Ken Siu, “PFC Boost Converter Design Guide,” Infineon Application Note, 2016.
        [Google Scholar]