First Author: Z. Chen

Correspondence Author: G. Yu*

Co-author: Y. Shi, A. Hu, J. Xu, and Chao Wang

Journal: IEEE International Conference on Integrated Circuits, Technologies and Applications (ICTA 2022)

Included Journals: EI

Discipline: Engineering

First-Level Discipline: Electronic Science And Technology

Document Type: C

Date of Publication: 2022-10-03

Abstract: This paper presents a novel fold-back current limiting protection circuit used in sub-threshold low dropout regulator (LDO) for wireless sensor applications. By utilizing negative feedback to sense the output current, converting the sampled current to voltage accurately and comparing with a reference voltage, the proposed protection circuit can control the gate voltage of the power transistor to limit the output current and reduce power consumption, thus achieving real-time monitoring of LDO in wireless sensor nodes. The maximum output current and short current of the sub-threshold LDO can be limited to 330 mA and 90 mA, respectively. This can save up to 71.9% of power consumption in the case of an output short-circuit condition compared with traditional constant current limiting protection methods. In a 0.35-μm CMOS technology, the sub-threshold LDO can provide a 3.3 V output voltage stably under the 5 V input voltage when the load current changes from 1 μA to 200 mA, and the load regulation rate is only 0.019 mV/mA.