A 240μW 17bit ENOB ΔΣ modulator using 2nd-order noise-shaped integrating quantizer

[摘要] This paper presents a discrete-time (DT) 4th-order ΔΣ modulator using a 2nd-order noise-shaped integrating quantizer (NSIQ). By adding a passive finite impulse response (FIR) filter to the 1st-order NSIQ, the proposed quantizer has obtained 2nd-order noise shaping ability, without extra power consumption. By incorporating the digital integrator, the linearity requirement of the quantizer is relaxed. The proposed modulator is fabricated in a 0.18μm CMOS process, and operates at 1MS/s achieves a peak signal-to-noise-and-distortion ratio (SNDR) of 106.9dB in a 10kHz bandwidth while consuming 240μW with 1.8V power supply.

[学科分类] 电子、光学、磁材料

[关键词] analog-to-digital conversion;ΔΣ modulator;noise enhancement circuit;noise-shaping quantizer