A 1.2-V 2.7-mW 160MHz continuous-time delta-sigma modulator with input-feedforward structure

Abstract

A power and area efficient continuous-time input-feedforward delta-sigma modulator (DSM) structure is proposed. The coefficients are optimized to increase the input range and reduce the power. The feedforward paths and the summer are embedded into the quantizer, hence the circuit is simplified, and the power consumption and area are reduced. The prototype chip, fabricated in a 0.13-μm CMOS technology, achieves a 68-dB DR (Dynamic Range) and 66.1-dB SNDR (signal-to-noise-and-distortion ratio) over a 1.25-MHz signal bandwidth with a 160MHz clock. The power consumption of the modulator is 2.7 mW under a 1.2-V supply, and the chip core area is 0.082mm2. © 2009 IEEE.