“…1, an SoC system contains a wide variety of analog, digital, and mixed-signal circuits. In addition, many of these circuits have been proposed with an ultralow supply voltage of 0.5 V, such as filters [3], analog-to-digital converters (ADCs) [4], digital-toanalog converters (DACs) [5], phase-locked loops (PLLs) [6], static random-access memory (SRAM) [7,8] and up-/down-conversion mixers [9]. LDOs are especially preferred in these low-power applications because of low-noise characteristics, a smaller size, and less complexity when compared with switching converters.…”