A novel on-chip linear and switching mixed regulation against power analysis attacks

On-chip voltage converters such as low drop-out (LDO) regulators are capable of generating fast and scaled voltage levels against power analysis attacks (PAAs) due to the high bandwidths of feedback loops. Unfortunately, LDO regulators suffer from much power loss when they are utilized for outputting scaled voltage levels. In contrast, buck converters may achieve high power conversion efficiencies but are unable to generate output voltage with fast scaling patterns. In this paper, a novel hybrid voltage regulator that is consist of an LDO regulator and a buck converter connected in parallel is proposed to address the issues related with security against PAAs and power loss. The LDO regulator offers fast scaled voltage levels while the buck converter provides major load current. The result shows that the measurement-to-disclosure (MTD) value of a cryptographic circuit (CC) with the proposed hybrid voltage regulator maintains over 2 million with a 4.3% power loss.