Optimum power-saving method for power MOSFET width of DC-DC converters

• Published in: IET circuits, devices & systems Vol. 1; no. 1; pp. 57 - 62
• Main Authors: CHEN, K.-H, CHIEN, C.-C, HSU, C.-H, HUANG, L.-R
• Format: Journal Article
• Language: English
• Published: Stevenage Institution of Engineering and Technology 01.02.2007; John Wiley & Sons, Inc
• Subjects: Applied sciences; Circuit properties; Circuits; Converters; Dynamics; Electric, optical and optoelectronic circuits; Electronic circuits; Electronic equipment and fabrication. Passive components, printed wiring boards, connectics; Electronics; Exact sciences and technology; Gates (circuits); MOSFETs; Optimization; Other multijunction devices. Power transistors. Thyristors; Reduction; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Signal convertors; Switching; Transistors; Performance evaluation; MOSFET; Power converter; Gate voltage; Direct current convertor; Driver; Power electronics; Switching convertors; Power transistor; Step down convertor; Low voltage; Error correction; Correcting circuit
• ISSN: 1751-858X; 1751-8598
• DOI: 10.1049/iet-cds:20050331

An optimum power metal-oxide-semiconductor field effect transistor (MOSFET) width technique is proposed for enhancing the efficiency characteristics of switching DC-DC converters. By implementing a one-cycle buck DC-DC converter, it is demonstrated that the dynamic power MOSFET width controlling technique has a much improved power reduction whether the load current is light or heavy. The maximum efficiency of the buck converter is ∼ 92% with a 3% efficiency improvement for the heavy load condition. The efficiency is further improved by ∼ 16% for the light load condition as a result of the power reduction from the large power MOSFET transistors. Also, proposed is a new error-correction loop circuit to enable a better load regulation than that of previous designs. Compared with the adaptive gate driver voltage technique, the optimum power MOSFET width can achieve a significant improvement in power saving. It is also superior to the low-voltage-swing MOSFET gate drive technique for switching DC-DC converters.