250 mV Supply Voltage Digital Low‐Dropout Regulator Using Fast Current Tracking Scheme. Issue 5 (1st October 2015)

• Record Type: Journal Article
• Authors: Oh, Jae‐Mun; Yang, Byung‐Do; Kang, Hyeong‐Ju; Kim, Yeong‐Seuk; Choi, Ho‐Yong; Jung, Woo‐Sung
• Is Part Of: ETRI journal. Volume 37:Issue 5(2015)
• Page Start: 961
• Page End: 971
• Publication Date: 2015-10-01
• Subjects: Digital regulator -- fast current tracking -- low‐dropout regulator -- LDO -- low voltage -- subthreshold; Telecommunication -- Periodicals; Electronics -- Periodicals; Electronics; Telecommunication; Periodicals; Periodicals; 621.38205
• DOI: 10.4218/etrij.15.0114.0985
• Languages: English
• ISSNs: 1225-6463

Abstract

Abstract : This paper proposes a 250 mV supply voltage digital low‐dropout (LDO) regulator. The proposed LDO regulator reduces the supply voltage to 250 mV by implementing with all digital circuits in a 0.11 μm CMOS process. The fast current tracking scheme achieves the fast settling time of the output voltage by eliminating the ringing problem. The over‐voltage and under‐voltage detection circuits decrease the overshoot and undershoot voltages by changing the switch array current rapidly. The switch bias circuit reduces the size of the current switch array to 1/3, which applies a forward body bias voltage at low supply voltage. The fabricated LDO regulator worked at 0.25 V to 1.2 V supply voltage. It achieved 250 mV supply voltage and 220 mV output voltage with 99.5% current efficiency and 8 mV ripple voltage at 20 μA to 200 μA load current.