An inner ESR-fungible compensation technique for ultra low power low dropout regulators

摘要

An inner ESR-fungible compensation technique was proposed in this paper to replace the conventional ESR compensation for low dropout regulator (LDO). This technique has been adopted in an ultra low power LDO, the quiescent current of which is only 0.9 μA and the static power consumption is less than 3 μW in typical condition. The proposed LDO can be stable enough with a small 1-μF ceramic capacitor by using this compensation technique, so it is very suitable for portable design due to the low cost and small PCB area. It has been fabricated based on a standard 0.5-μm CMOS technology, and the validity and feasibility of the proposed compensation method has been proved by the measurement results.