A Wide Frequency Range LLC Resonant Controller IC with a Phase-Domain Resonance Deviation Prevention Circuit for LED Backlight Units

Park, YoungJun;Kim, Hongjin;Chun, Joo-Young;Lee, JooYoung;Pu, YoungGun;Lee, Kang-Yoon

  • Received : 2014.10.25
  • Accepted : 2015.03.06
  • Published : 2015.07.31


This paper presents a wide frequency range LLC resonant controller IC for LED backlight units. In this paper a new phase-domain resonance deviation prevention circuit (RDPC), which covers a wide frequency and input voltage range, is proposed. In addition, a wide range gate clock generator and an automatic dead time generator are proposed. The chip is fabricated using 0.35 μm BCD technology. The die size is 2 x 2 mm2. The frequency of the clock generator ranges from 38 kHz to 400 kHz, and the dead time ranges from 300 ns to 2 μs. The current consumption of the LLC resonant controller IC is 4 mA for a 100 kHz operation frequency using a supply voltage of 15 V.


Backlight unit;Clock generator;Dead time;LED driver;LLC resonant controller;Prevention Circuit (RDPC);Resonance Deviation;Wide range


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