Research On Calibration Method Of High-precision Digital-to-analog Converter Based On Electronic Measuremen

With the rapid development of modern communication,high-precision Digital-to-analog Converter（DAC）is widely used in industry,national defense,scientific research and other fields.In metrology,DACs with good static properties play a very important role in the transmission of DC voltage reference.Now,the National Institute of Standards and Technology（NIST）and the National Institute of Metrology（NIM）have established measuring standard devices of the static properties of DAC,but the devices are large and costly.Therefore,it is important to develop a fast,small,and low-cost system for static property calibration of high-precision DACs.A differential calibration method based on internal standard is proposed to solve the problem that existing high-precision static characteristic calibration systems are large,expensive and unable to adapt to high pressure voltage environment.Firstly,the measurement method of the system is analyzed in this thesis,and the differential measurement method is used to greatly reduce reference source error,the requirement of linearity and common-mode rejection ratio of voltmeter is greatly reduced.Then,a high-precision DC voltage ratio self-calibration system is designed in this thesis as a standard,based on the built-in standard measuring scheme commonly used in the world.The binary resistive divider proposed by Cutkosky and a commercial DAC are combined to increase the resolution of the system.At the same time,a new combination-buffer structure and combination-adder structure are proposed,which can theoretically reduce the loop gain error and common mode error to 10^-10 orders of magnitude.The DAC calibration method designed in this thesis has the following advantages:（1）This thesis proposes a new 10:1 proportional self-calibration structure,which realizes 1000:1 high-precision voltage proportional output by cascading method,thus theoretically realizing the static characteristic calibration up to 1000 V DAC,so that the system can play a role in the transmission of high voltage value reference.（2）Compared with the international advanced DAC static characteristic calibration method,this thesis realizes the miniaturization and portability of the calibration equipment,and the whole system is placed in the standard 4U chassis.At the same time,the low cost of calibration equipment is realized.The cost of the high-precision DC voltage proportional self-calibration system proposed as the standard in this thesis is less than 20,000 yuan.In addition,the systematic errors are analyzed in detail and verified by practical tests.The results show that the system has a resolution of 27 bits,21 bits effectively,offset error（OE）better than 0.3 LSB,gain error（GE）better than 1 ppm FSR,and integral nonlinearity（INL）better than 0.5 LSB.It plays a very important role in the transmission of DC voltage reference.