An Ultra-Low Voltage Digitally Controlled Low-Dropout Regulator with Digital Background Calibration

Yongtae Kim and Peng Li
Texas A&M University


In this paper, we describe a novel ultra-low voltage digitally controlled low-dropout (LDO) voltage regulator offering digitally controllable dynamic voltage scaling (DVS) for near/sub-threshold applications. We eliminate the reference voltage in conventional LDOs and adopt the reference clock that enables the proposed LDO to be controlled digitally. The analog components are replaced by digital counterparts which are able to operate at near/sub-threshold regime. Additionally, a digital background calibration scheme is proposed to minimize the regulated voltage errors due to process, voltage, and temperature (PVT) variations.