This paper presents an innovative general structure for a single-loop Sigma-Delta ($\mathrm{\Sigma }\mathrm{\Delta }$) modulator that combines low-distortion and noise-coupled techniques to achieve high-resolution for low-power applications. The low-distortion technique adjusts the signal transfer function of the proposed structure to unity, while the noise-coupled technique enhances the order of quantization noise-shaping at the modulator output. These techniques were incorporated into the design to increase the modulator order without requiring additional operational amplifiers during its circuit implementation, resulting in a low-power modulator compared to similar structures. To reduce the number of required amplifiers, a second-order infinite impulse response (IIR) filter was used in the modulator loop filter, in place of two integrators. To assess the proposed structure’s performance, a third-order modulator sample was implemented and simulated for speech recognition applications, specifically, digital hearing aids, using 180$$nm complementary metal oxide semiconductor (CMOS) technology. The results indicate that for a third structure with a sampling rate of 64, an input sine signal of −6$$dBFS and a sampling frequency of 2.56$$MHz, the signal to noise plus distortion (SNDR) was 81.9$$dB, and the dynamic range (DR) was 88$$dB for a 20$$KHz bandwidth. The modulator’s power consumption was 126.9$$$\mu$W. Circuit and system-level simulations demonstrate the effectiveness of the proposed method.

本文提出了一种单环 Sigma-Delta 的创新通用结构（$\mathrm{\Sigma }\mathrm{\Delta }$）调制器，结合了低失真和噪声耦合技术，可为低功耗应用实现高分辨率。低失真技术将所提出的结构的信号传递函数调整为统一，而噪声耦合技术增强了调制器输出处的量化噪声整形的阶数。这些技术被纳入设计中，以增加调制器阶数，而在电路实现过程中不需要额外的运算放大器，从而与类似结构相比，调制器的功耗较低。为了减少所需放大器的数量，在调制器环路滤波器中使用二阶无限脉冲响应 (IIR) 滤波器来代替两个积分器。为了评估所提出的结构的性能，针对语音识别应用（特别是数字助听器）实现并模拟了三阶调制器样本，使用 180$$纳米互补金属氧化物半导体（CMOS）技术。结果表明，对于采样率为 64 的第三种结构，输入正弦信号为 -6$$dBFS 和采样频率 2.56$$MHz，信噪加失真 (SNDR) 为 81.9$$dB，动态范围（DR）为88$$20分贝$$KHz 带宽。调制器的功耗为126.9$$$\mu$W.电路和系统级仿真证明了所提出方法的有效性。