12-bit ultra-low power low voltage analog to digital converter design for an infrared imaging system

Abstract

This Final Year Project is to design a 12-bit ultra-low power analog-to-digital converter (ADC). This ADC design is used as part of an on-going NTU research project--development of a Multispectral Infrared Detector Arrays on Read-Out Integrated Circuit (MIDAS-on-ROIC).

The main concern for this ADC design is power consumption due to several system reasons. First of all, the MIDAS-on-ROIC system requires low-power operation for its high sensitivity. Secondly, the ADC can dissipate large amount of power in infrared systems. Based on Successive Approximation Register (SAR) approach, the original designed ADC achieves 12-bit resolution at sampling rate of 20 ksps and dissipates 16.6μW with 3.3 V power supply. The designed ADC is expected to operate in -40 0C or lower temperature environment. After adopting corresponding design techniques as well as special power saving techniques, the ADC design is free from accuracy, resolution problems without sacrificing conversion speed. The power consumption, at the mean time, is also significantly reduced compared to traditional ADC design.