An area-saving and high power efficiency charge pump built in a TFT-LCD driver IC

• Published in: Journal of semiconductors Vol. 30; no. 9; pp. 129 - 134
• Main Author: 郑然 魏廷存 王佳 高德远
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.09.2009
• Subjects: LCD驱动器; TFT; 内置; 功率效率; 收费; 电荷泵; 驱动IC; 驱动集成电路
• ISSN: 1674-4926
• DOI: 10.1088/1674-4926/30/9/095015

An area-saving and high power efficiency charge pump is proposed, and methods for optimizing the operation frequency and improving the power efficiency are discussed. Through sharing coupling capacitors the proposed charge pump realizes two DC-DC functions in one circuit, which can generate both positive and negative high voltages. Due to sharing of the coupling capacitors, as compared with a previous charge pump designed by us for a TFT-LCD driver IC, the die area and the amounts of necessary external capacitors are reduced by 40% and 33%, respectively. Furthermore, the charge pump＇s power efficiency is improved by 8% as a result of employing the new topology. The designed circuit has been successfully applied in a one-chip TFT-LCD driver IC implemented in a 0.18 μm low/mid/high mixed-voltage CMOS process.