Active EMI Reduction Using Chaotic Modulation in a Buck Converter with Relaxed Output LC Filter

Electronics

HaiAu Huynh¹  SoYoung Kim¹  VanHa Nguyen²  Hanjung Song² 

[1] Department of Electronic, Electrical and Computer Engineering, College of Information and Communication Engineering, Sungkyunkwan University, Suwon, Gyeonggi-do 16410, Korea;Department of Nanoscience and Engineering, Nano Circuit Design Laboratory, Inje University, Gimhae, Gyeongsangnam-do 05834, Korea;

关键词: electromagnetic interference;    chaotic PWM;    DC-DC buck converter;    CMOS chaotic circuit;    triangular ramp generator;    spread-spectrum technique;    system in package;   

DOI  :  10.3390/electronics7100254

来源: DOAJ

【 摘 要 】

DC-DC buck converters are widely used in portable applications because of their high power efficiency. However, their inherent fast switching releases electromagnetic emissions, making them prominent sources of electromagnetic interference (EMI). This paper proposes a voltage-controlled buck converter that reduces EMI by using a chaotic pulse-width modulation (PWM) technique based on a chaotic triangular ramp generator. The chaotic triangular ramp generator is constructed from a simple on-chip chaotic circuit linked with a symmetrically triangular ramp circuit. The proposed converter can thus operate in the chaotic mode reducing the EMI without requiring any EMI filters. Additionally, using the triangular ramp signal can relax the requirement for a large LC output filter in chaotic mode. The effectiveness of the proposed scheme was experimentally verified with a chaotic triangular ramp generator embedded in a voltage-mode controller buck converter using a 0.18 µm Complementary Metal Oxide Semiconductor (CMOS) process. The measurement results from a prototype showed that the EMI improvement from the proposed scheme is approximately 14.53 dB at the fundamental switching frequency with respect to the standard fixed-frequency PWM reference case.

【 授权许可】

Unknown