A novel level shifter for practical IoT applications

Abstract

This paper proposed a 0.5 V–1.32 V input to 3.3 V output voltage level shifter (LS) that meets both requirements for current IoT applications, namely a minimal 0.7 V input voltage and 500 MHz speed at nominal 1.2 V. Simulations of this LS using a commercial 55-nm process design kit demonstrated a minimal input voltage in the near-threshold region (500 mV) and speeds in the GHz range when running at 1.2 V nominally. This was achieved using an isolation control signal to time the half-latch that switches input and output voltage, and a NAND gate as an inverting buffer for data transferring in active state or a pull high logic in isolation state. Besides, the proposed LS exhibits average static power of less than 70 pW and a small area consumption which is suitable for IoT applications.