A Fully Differential Comparator-Based Switched-Capacitor Delta Sigma Modulator

作者：Huang Mu Chen^*; Liu Shen Iuan

来源：IEEE Transactions on Circuits and Systems II-Express Briefs, 2009, 56(5): 369-373.

DOI：10.1109/TCSII.2009.2019166

• Common-mode feedback (CMFB)
• comparator-based switched-capacitor (CBSC) circuits
• delta-sigma (Delta Sigma) modulator
• fully differential

In this brief, a fully differential comparator-based switched-capacitor (CBSC) second-order delta-sigma (Delta Sigma) modulator is presented. To ensure differential operation, the CBSC Delta Sigma modulator utilizes a common-mode feedback circuit to balance the pull-up current and the pull-down current in the ramp generator. This modulator has been fabricated in a standard 0.18-mu m CMOS process. The active area is 0.21 mm(2), and the power consumption, excluding output buffers, is 0.42 mW from a 1.8-V supply. This modulator achieves 65.3-dB signal-to-noise-plus-distortion ratio and an input dynamic range of 71 dB when sampled at 2.56 MS/s (OSR = 64).

• 出版日期2009-5
• 单位中国科学院电工研究所