高精度数模转换器的线性度测试技术  

Linearity Testing Technology of High Precision Digital-to-Analog Converter

作　　者：陈宇轩 季伟伟 解维坤 张凯虹 寿开元 CHEN Yuxuan;JI Weiwei;XIE Weikun;ZHANG Kaihong;SHOU Kaiyuan(China Key System&Integrated Circuit Co.,Ltd.,Wuxi 214072,China;School of Automation Engineering,University of Electronic Science and Technology of China,Chengdu 611731,China)

机构地区：[1]中科芯集成电路有限公司,江苏无锡214072 [2]电子科技大学自动化工程学院,成都611731

出　　处：《电子与封装》2023年第5期7-12,共6页Electronics & Packaging

摘　　要：高精度数模转换器(DAC)测试一直是混合信号测试的难点。线性度是DAC静态误差的重要指标,包括积分非线性(INL)误差和微分非线性(DNL)误差2个参数。针对如何高效、准确地测试高精度DAC的线性度这一问题,使用最小二乘法转换曲线拟合算法进行线性度计算。同时基于电流型DAC的内部结构,提出了1种利用特征点测试DAC线性度的优化方法。使用V93000自动测试设备对16位DAC进行验证,优化前的INL测试结果为-1.88 LSB,DNL测试结果为1.202 LSB,优化后的INL测试结果为-1.24 LSB,DNL测试结果为0.594 LSB。结果表明,使用特征点结合最小二乘法拟合转换曲线算法能够有效提高线性度的测试结果,同时将测试时间由7 s缩减至1 s,避免了因长时间测试电阻产生温漂引起的误差,测试效率和测试精度均得到提升。The test of high precision digital-to-analog converter(DAC)is always the difficulty of mixed signal test.Linearity is an important indicator of DAC static error,including two parameters,integral nonlinear(INL)error and differential nonlinear(DNL)error.Aiming at the problem of how to test the linearity of high precision DAC efficiently and accurately,the least square method is used to convert the curve fitting algorithm to calculate the linearity.At the same time,based on the internal structure of current mode DAC,an optimization method using characteristic points to test the linearity of DAC is proposed.The V93000 automatic test equipment is used to verify the 16 bit DAC.The INL test result is-1.88 LSB,the DNL test result is 1.202 LSB before optimization,the INL test result is-1.24 LSB,and the DNL test result is 0.594 LSB after optimization.The results show that the test results of linearity can be effectively improved by using the characteristic points combined with the least square method to fit the conversion curve algorithm.At the same time,the test time is reduced from 7 s to 1 s.The test error caused by the temperature drift of the test resistance for a long time is avoided,and the test efficiency and precision are improved.

关 键 词：数模转换器 微分非线性 积分非线性 最小二乘法 特征点 

分 类 号：TN407[电子电信—微电子学与固体电子学] TN45