Title :
A High-Efficiency Wide-Input-Voltage Range Switched Capacitor Point-of-Load DC–DC Converter
Author :
Ng, Vincent W. ; Sanders, S.R.
Author_Institution :
Volterra Semicond., Fremont, CA, USA
Abstract :
The traditional inductor-based buck converter has been the default design for switched-mode voltage regulators for decades. Switched capacitor (SC) dc-dc converters, on the other hand, have traditionally been used in low-power (<;10 mW) and low conversion ratio (<;4:1) applications where neither regulation nor efficiency is critical. This study encompasses the complete successful design, fabrication, and test of a CMOS-based SC dc-dc converter, addressing the ubiquitous 12-1.5 V boardmounted point-of-load application. In particular, the circuit developed in this study attains higher efficiency (92% peak, and >80% over a load range of 5 mA to 1 A) than surveyed competitive buck converters, while requiring less board area and less costly passive components. The topology and controller enable a wide input range of 7.5-13.5 V. Controls based on feedback and feedforward provide tight regulation under worst case line and load step conditions. This study shows that the SC converter can outperform the buck converter, and thus, the scope of SC converter application can and should be expanded.
Keywords :
CMOS integrated circuits; DC-DC power convertors; low-power electronics; network topology; switched capacitor networks; CMOS-based SC DC-DC converter; current 5 mA to 1 A; high-efficiency wide-input-voltage range switched capacitor point-of-load DC-DC converter; inductor-based buck converter; switched-mode voltage regulators; voltage 12 V to 1.5 V; Capacitors; Clocks; Switches; Switching frequency; Voltage control; Voltage measurement; DC-DC power converters; switched capacitor circuits; switched-mode power supply;
Journal_Title :
Power Electronics, IEEE Transactions on
DOI :
10.1109/TPEL.2012.2224887