一种单环5阶高精度音频Δ-Σ A/D转换器

A Single-Loop 5^(th)-Order High Precision Stereo Δ-Σ A/D Converter

采用英飞凌0.11μm CMOS工艺,实现了一种用于音频范围的高精度Δ-ΣA/D转换器。调制器采用1位量化的5阶单环前馈结构,ADC过采样率为256。A/D转换器模拟调制器工作于5V电压,数字滤波器工作于1.2V电压,整体功耗为20.52mW,版图面积3.1mm2。仿真结果显示,设计的A/D转换器在20kHz信号带宽内达到108.9dB的信噪失真比,有效位数为18位。

Based on Infineon＇s 0.11 μm CMOS process,a high-precision stereo Δ-Σ A/D converter（ADC） was implemented.In this ADC,a single-bit quantized single-loop 5th-order feed forward structure was adopted for the modulator,and its over-sampling rate（OSR） reached 256.The analog modulator and digital filter operated at 5 V and 1.2 V,respectively.The ADC had a total power consumption of 20.52 mW,and the circuit occupied a die area of 3.1 mm2,including pad ring.Simulation results showed that the ADC achieved an ENOB of 18 bits and an SNDR of 108.9 dB over a signal bandwidth of 20 kHz