PROGRESS: Completed Project	PROJECT REF: PA115
PROJECT TITLE: Switched-Opamp Technique for Low-Voltage Switched-Capacitor Circuits
PROJECT DESCRIPTION: A new switched-opamp technique is proposed to operate switched-capacitor circuits at supply voltages as low as 1-V without on-chip voltage multiplier or low-Vt devices. The main idea of the new switched-opamp technique is to implement an additional switchable operational amplifier (opamp) in parallel but in an alternate clock phase compared to the original switched opamp. As such, for every clock phase, there exists an opamp that is fully functional in the switched-capacitor system. The two switchable opamps are further combined to realize a single two-switchable-output-pair opamp to save power and area and to minimize the mismatch. Unlike existing ones, the proposed switched-opamp technique can be directly applied to implement most of the existing classical switched-capacitor circuits and is highly compatible with their synthesizing techniques. By using the new technique, switched-capacitor circuits can be designed to operate at high frequencies with only a single 1-V supply in a standard CMOS process. Potential Applications: - All existing switched-capacitor circuits, in particular filters and analog-to-digital converters - Low-voltage high-frequency applications, including wireless and telecommunications Advantages over Present Technologies: In the proposed switched-opamp technique, the opamps allow multi-phase operation, making it fully functional at any time, and consequently can be combined with other switched-capacitor techniques to achieve higher performance in terms of speed, supply voltage, and power consumption. As such, it can be applied to implement high-performance switched-capacitor filters and analog-to-digital converters for wireless and telecommunication applications.
FOCUS AREA(S): Integrated Circuit Design, Consumer Electronics
KEYWORDS: switched-capacitor circuits, converter, digital converter, analog-to-digital converter, low voltage,
MODE OF COLLABORATION: Technology Licensing, Further R&D Collaboration
STATUS PATENT: Granted	PATENT NO: US6344767, Chinese PCT pending, European PCT pendi
ORGANIZATION: Hong Kong University of Science and Technology R and D Corporation Limited
CONTACT PERSON: Shirley Woo	EMAIL: cawoosw@ust.hk
TEL: (852)-23587918	FAX: (852)-23582751
WEBSITE: http://rdc.ust.hk/	DATE: 29/12/2004