Dither技术结合过采样技术提高ADC采集精度的研究

Research on Improving ADC Acquisition Accuracy by Combining Dither Technology with Oversampling Technology

摘要: Dither技术和过采样技术可以改善模数转换器(ADC)的采集精度。本文研究了Dither技术结合过采样技术的方法，ADC的差分端引入Dither信号，并在ADC后端去除，而后采用过采样技术对信号滤波抽取，将ADC的信噪比(Signal to Noise Ratio, SNR)、信纳比(Signal to Noise and Distortion Ratio, SINAD)和无散杂动态范围(Spurious Free Dynamic Range, SFDR)，分别提升了6.59 dB、6.89 dB和19.05 dB，使得ADC有效位数提升了1位。

Abstract: Dither technology and oversampling technology can improve the acquisition accuracy of analog-to-digital converter (ADC). This paper studies the method of combining the Dither technique with the oversampling technique. The Dither signal is introduced into the differential end of the ADC and removed at the back end of the ADC. Then, the oversampling technique is used to filter and decimate the signal. The signal to noise ratio (SNR), signal to noise and distortion ratio (SINAD) and spurious free dynamic range (SFDR) of the ADC are increased by 6.59 dB, 6.89 dB and 19.05 dB respectively, so that the ADC significant bit is increased by 1 bit.