Abstract: A behavioral simulation method is proposed for both system level and behavioral level design of Sigma-Delta ADCs (analog to digital converters).Compared with traditional behavioral simulation methods，the proposed method has a higher simulating speed and is more efficient in the behavioral design.With this simulation method，the imperfections of the analog cells as integrators，comparator，and the Op-Amps are analyzed in detail，which guides the design towards high performance. As a proof for the effectiveness of this method，a second-order Sigma-Delta modulator was designed and fabricated using a 0.13 μm mixed signal CMOS technology.The test results show that the modulator can achieve a peak SNR of 77.2 dB，which equals to a 12.5 bit resolution，and a power dissipation of 5.9 mW (6.2 mW with decimator) was occupied.

Key words: behavioral simulation, circuit imperfections, Sigma-Delta ADC

摘要： 提出了一种行为级仿真方法，可以用于Sigma-Delta模数转换器系统级和行为级设计。与传统的行为级设计方法相比，该方法拥有更高的速度，更加易于使用，并且对于行为级设计来说有更高的效率。采用这种仿真方法，能详细分析模拟电路单元的非理想特性如积分器、比较器、运算放大器等，有助于实现高性能设计。为了验证该设计方法的有效性，设计了一个二阶Sigma-Delta模数转换器，并采用0.13μm混合信号CMOS工艺进行了流片。测试结果显示，调制器可以实现77.2dB的最高信噪比，相当于12.5位量化精度，而功耗仅为5.9mW(包括抽取滤波器为6.2mW)。

关键词: 电路非理想特性, Sigma-Delta模数转换器, 行为级仿真