A single supply level shifter for multi-voltage systems

Abstract

This paper presents design and application of a level shifter circuit which works with a single power supply. Unlike the conventional level shifter circuits, the proposed level shifter can shift any voltage level signal to a desired higher level without any leakage current. Use of single supply level shifter greatly reduces the supply routing and layout congestion within the chip when level shifting is required between different voltage domains. It also reduces pin count if level shifting is required between two or more chips operating at different supply voltages in a multi-voltage system. The proposed circuit is generic in nature and the voltage range at which level shifting can be done is limited by the technology only. The circuits was designed in 90nm CMOS technology and simulated in SPICE. The simulation results show that the proposed level shifter circuit is able to shift the input signal from 1.2V to 2.5V at maximum frequency of 500MHz.