Total Harmonic Distortion Adjustment Method and Circuit for LED AC Direct Driver IC

A novel scheme of total harmonic distortion (THD) adjustment for light-emitting diode (LED) alternating current (AC) direct driver integrated circuit (IC) is presented. The current flowing through the LED strings can be changed by using a plurality of THD adjustment modules and external resistors RTDs corresponding thereto. Consequently, the THD is adjusted. In addition, RTDs can be changed by users to achieve a small THD in different situations, like different AC power supply and different voltage drop distribution scheme of the LED strings. The proposed THD adjustment scheme is implemented in a 1μm high-voltage Bipolar-CMOS-DMOS process. Simulation results show that the proposed method can significantly reduce THD and is suitable for all types of cases.

[1]  Tsutomu Yoshihara,et al.  AC direct multiple-string LED driver with low THD and minimum components , 2015, 2015 International SoC Design Conference (ISOCC).

[2]  Junsik Kim,et al.  A soft self-commutating method using minimum control circuitry for multiple-string LED drivers , 2013, 2013 IEEE International Solid-State Circuits Conference Digest of Technical Papers.

[3]  Chunyan Feng,et al.  Self-adaptive load technology for multiple-string LED drivers , 2013 .

[4]  Dianguo Xu,et al.  A high-power-factor integrated-stage AC-DC LED driver based on flyback-class E converter , 2017, 2017 IEEE Industry Applications Society Annual Meeting.

[5]  Yuan Gao,et al.  22.8 An AC-input inductorless LED driver for visible-light-communication applications with 8Mb/s data-rate and 6.4% low-frequency flicker , 2017, 2017 IEEE International Solid-State Circuits Conference (ISSCC).

[6]  Yuan Gao,et al.  An AC Input Switching-Converter-Free LED Driver With Low-Frequency-Flicker Reduction , 2017, IEEE Journal of Solid-State Circuits.

[7]  Philip K. T. Mok,et al.  A multiple-string hybrid LED driver with 97% power efficiency and 0.996 power factor , 2016, 2016 IEEE Symposium on VLSI Technology.