An All-Thin-Devices Level Shifter in Standard-Cell Format for Auto Place-and-Route Flow

Abstract

This paper proposes a standard-cell format all-thin-devices level shifter suited for commercial digital-flow tools. Despite the fact that it is possible to find commercial level-shifter cells in standard-cell format, those cells require a mixed of thick- and thin-devices. The use of only thin-oxide transistors allows placing level shifters within thin-device based digital cells, optimizing area and place-and-route process. Due to the maximum voltage ratings of thin transistors, we adopted a switching technique to prevent high voltage differences between their terminals, avoiding a possible device breakdown. The proposed level shifter occupies an area of 156µm2 in a 0.18µm CMOS node.