中圖分類號(hào)： TN432
文獻(xiàn)標(biāo)識(shí)碼： A
DOI：10.16157/j.issn.0258-7998.211398
中文引用格式： 劉銘揚(yáng)，王小松，劉昱. 一種帶有DAC失配整形的高精度Sigma-Delta調(diào)制器[J].電子技術(shù)應(yīng)用，2021，47(9)：25-29，38.
英文引用格式： Liu Mingyang，Wang Xiaosong，Liu Yu. A high precision multi-bit sigma-delta modulator with mismatch-shaping DACs[J]. Application of Electronic Technique，2021，47(9)：25-29，38.

A high precision multi-bit sigma-delta modulator with mismatch-shaping DACs

Abstract： In order to reduce the difficulty of designing the amplifier of the instrument in the application of physiological signal acquisition, a higher-precision analog-to-digital conversion unit is required. This paper implements a high-precision sigma-delta modulator with feedforward structure, which does not require complex OTA structure and high oversampling rate, and has low power consumption, and a second-order noise shaping dynamic component matching scheme used in DAC to avoid nonlinear harmonic distortion caused by multi-bit quantization. The sigma-delta modulator adopts SMIC 0.18 μm CMOS standard technology. At a sampling frequency of 1 MHz and a signal bandwidth of 1 kHz, the peak SNDR can reach 111 dB, the operating power supply voltage is 1.8 V, and the overall power consumption is 0.87 mW.

Key words : sigma-delta modulator；multi-bit quantizer；2nd-order dynamic element matching；successive approximation；feed-forward