This paper revisits histogram method for ADC linearity test. Here two methods are proposed for low cost test of histogram method. The first proposal is two-tone sine wave input for code selective histogram method for SAR ADC. In SAR ADC, the DNL of the codes corresponding to the internal DAC output voltages of the MSB bits can be large when the DAC employs a binary-weighted configuration. Therefore, in the proposed method, frequency of appearance of the codes is increased to make the length of the bins relatively long with two-tone sine wave input. It realizes low cost test and high-quality linearity test. The 2nd proposal is decision method of the ratio of the input and sampling frequencies with classical number theory. The proposed method decides the ratio based on metallic ratio or theory of prime numbers. This guarantees random data sampling to get accurate calibration result with relatively small number of histogram data.

本文重新审视了 ADC 线性度测试的直方图方法。这里提出了两种方法用于直方图方法的低成本测试。第一个建议是用于 SAR ADC 的代码选择直方图方法的双音正弦波输入。在 SAR ADC 中，当 DAC 采用二进制加权配置时，对应于内部 DAC 输出电压的 MSB 位的代码的 DNL 可能会很大。因此，在所提出的方法中，增加了代码的出现频率，以使带有双音正弦波输入的 bin 的长度相对较长。它实现了低成本的测试和高质量的线性测试。第二个建议是使用经典数论的输入频率与采样频率之比的决策方法。所提出的方法根据金属比率或素数理论来确定比率。