A 3.68aFrms Resolution 183dB FoMs 4th-order Continuous-Time Bandpass ∆Σ Capacitance-to-Digital Converter in 0.18µm CMOS

Abstract

This paper presents an ultra-high-resolution energy-efficient 4th-order continuous-time (CT) bandpass (BP) ∆Σ capacitance-to-digital converter (CDC) where thermal noise folding is avoided by CT operation and power is saved by using a BP ∆Σ architecture. The proposed CDC achieves a resolution of 3.68 aFrms at room temperature while achieving a Schreier figure-of-merit (FoMS) of 183dB which is more than 2x improvement over the state-of-the-art CDCs.