A 0.9-mu A Quiescent Current Output-Capacitorless LDO Regulator With Adaptive Power Transistors in 65-nm CMOS

作者：Chong Sau Siong^*; Chan Pak Kwong

来源：IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-REGULAR PAPERS, 2013, 60(4): 1072-1081.

DOI：10.1109/TCSI.2012.2215392

• LDO regulator
• output-capacitorless LDO regulator
• OCL-LDO regulator
• ultra-low quiescent LDO
• multi gain stage LDO

An ultra-low quiescent current output-capacitorless low-dropout (OCL-LDO) regulator with adaptive power transistors technique is presented in this paper. The proposed technique permits the regulator to transform itself between 2-stage and 3-stage cascaded topologies with respective power transistor, depending on the load current condition. As such, it enables the OCL-LDO regulator to achieve ultra-low power consumption, high stability and good transient response without the need of off-chip capacitor at the output. The proposed LDO regulator has been implemented and fabricated in a UMC 65-nm CMOS process. It occupies an active area of 0.017 mm(2). The measured results have shown that the proposed circuit consumes a quiescent current of 0.9 mu A at no load, regulating the output at 1 V from a voltage supply of 1.2 V. It achieves full range stability from 0 to 100 mA load current at a maximum 100 pF parasitic capacitance load. The measured transient output voltage is 68.8 mV when load current is stepped from 0 to 100 mA in 300 ns with C-L = 100 pF. The recovery time is about 6 mu s. Compared to previously reported counterparts, the proposed OCL-LDO regulator shows a significant improvement in term of OCL-LDO transient figure-of-merit (FOM) as well as balanced performance parameters in terms of PSR, line regulation and load regulation.

• 出版日期2013-4