Design of Flash analog-to-digital converter based on MoS2 FET

Abstract

In this paper, we leverage the advantages of MoS2 FETs to design a 4-bit Flash ADC that achieves a reduced active area and dynamic power. The proposed ADC employs a threshold inverter quantization (TIQ) technique to eliminate static power dissipation. A SPICE-compatible charge-based model for MoS2 FETs is used to simulate the proposed ADC. The high ON/OFF current ratio and nanoscale size of MoS2 FETs contribute to a smaller ADC active area and lower dynamic power compared to other technologies. Simulation results indicate a differential nonlinearity (DNL) of [−0.18, 0.12]LSB and an integral nonlinearity (INL) of [−0.32, 0.24]LSB meeting the requirements for 4-bit resolution at a 2 V operating voltage. While the FFT spectrum analysis reveals a signal-to-noise ratio (SNR) of 29.37 dB, the effective resolution bandwidth (ERBW) of 2.2 GHz is obtained, highlighting the ADC’s performance in high-speed applications. Additionally, the low ADC active area of 3000 μm2 makes it suitable for very large-scale integration (VLSI) circuits. The proposed method is sensitive to variations in process, temperature, and power supply voltage, and their effects on ADC performance are also examined.