A third-order complementary metal-oxide-semiconductor sigma-delta modulator operating between 4.2K and 300 K KU Leuven
This paper presents a third-order switched-capacitor sigma-delta modulator implemented in a standard 0.35-μm CMOS process. It operates from 300 K down to 4.2 K, achieving 70.8 dB signal-to-noise-plus-distortion ratio (SNDR) in a signal bandwidth of 5 kHz with a sampling frequency of 500 kHz at 300 K. The modulator utilizes an operational transconductance amplifier in its loop filter, whose architecture has been optimized in order to eliminate ...