A 23 mW, 73 dB Dynamic Range, 80 MHz BW Continuous-Time Delta-Sigma Modulator in 20 nm CMOS

Abstract

This paper presents a continuous-time ΔΣ modulator targeted at optimizing power efficiency for input bandwidth exceeding 50 MHz. Delay in the feedback path is carefully minimized and traditional techniques for DAC mismatch correction and excess loop delay compensation are both replaced with digital schemes. Power is also minimized by relaxing loop filter BW requirements and using a power efficient opamp topology. The modulator achieves 73 dB dynamic range (DR) in 80 MHz BW while consuming 23 mW. The peak SNR is 70 dB and the peak SNDR is 67.5 dB, resulting in FOMs of 168 dB and 163 dB based on DR and SNDR, respectively.