A Wide-Range Level Shifter Using a Modified Wilson Current Mirror Hybrid Buffer

• Published in: IEEE transactions on circuits and systems. I, Regular papers Vol. 61; no. 6; pp. 1656 - 1665
• Main Authors: Luo, Shien-Chun, Huang, Ching-Ji, Chu, Yuan-Hua
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.06.2014; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Circuits; Current mirror; Current mirrors; Delays; Design engineering; dynamic voltage scaling; Dynamical systems; Dynamics; Electric potential; level shifter; Logic; Logic gates; Mirrors; MOS devices; Power demand; process variation; standard cell library; subthreshold circuit; Transistors; Voltage
• ISSN: 1549-8328; 1558-0806
• DOI: 10.1109/TCSI.2013.2295015

Wide-range level shifters play critical roles in ultra- low-voltage circuits and systems. Although state-of-the-art level shifters can convert a subthreshold voltage to the standard supply voltage, they may have limited operating ranges, which restrict the flexibility of dynamic voltage scaling. Therefore, this paper presents a novel level shifter, of which the operating range is from a deep subthreshold voltage to the standard supply voltage and includes upward and downward level conversion. The proposed level shifter is a hybrid structure comprising a modified Wilson current mirror and generic CMOS logic gates. The simulation and measurement results were verified using a 65-nm technology. The minimal operating voltage of the proposed level shifter was less than 200 mV based on the measurement results. In addition to the operating range, the delay, power consumption, and duty cycle of the proposed level shifter were designed for practical applications.