Title :
A small ripple regulated charge pump with automatic pumping control schemes
Author :
Kim, Sung-Eun ; Song, Seong-Jun ; Kim, Jin Kyung ; Kim, Sunyoung ; Lee, Jae-Youl ; Hoi-Jun Yoo
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Korea Adv. Inst. of Sci. & Technol., Daejeon, South Korea
Abstract :
Two schemes for a charge pump are presented, to reduce output ripple voltage, with high load current drivability. The first is an automatic pumping current control scheme which automatically adjusts the size of the pumping driver to reduce the ripple voltage. The second is an automatic pumping frequency control scheme, which changes the pumping period by controlling a VCO. The prototype chip provides 30-mA load current and delivers a regulated 4.5-V output with a flying capacitor of 330-nF and a clock frequency which automatically varies from 400-kHz to 600-kHz at a 3.3-V supply. The area is 0.25 mm2 in a 3.3-V 0.13-μm CMOS technology, and measured output ripple voltage is less than 33.8-mV with 2-μF load capacitor. Power efficiency is higher than 70%.
Keywords :
CMOS integrated circuits; DC-DC power convertors; driver circuits; switching convertors; voltage regulators; voltage-controlled oscillators; 0.13 micron; 2 muF; 3.3 V; 30 mA; 33.8 mV; 330 nF; 4.5 V; 400 to 600 kHz; 70 percent; CMOS; VCO; automatic charge pumping control; flying capacitor; high load current drive; low ripple regulated charge pump; output ripple voltage reduction; power efficiency; pumping current control; pumping driver; pumping frequency control; Automatic control; CMOS technology; Capacitors; Charge pumps; Clocks; Current control; Frequency control; Prototypes; Voltage; Voltage-controlled oscillators;
Conference_Titel :
Solid-State Circuits Conference, 2004. ESSCIRC 2004. Proceeding of the 30th European
Print_ISBN :
0-7803-8480-6
DOI :
10.1109/ESSCIR.2004.1356698