Test adapter and test method for analog-to-digital converter nonlinear parameters

Abstract

The invention discloses a test adapter for analog-to-digital converter nonlinear parameters. The test adapter comprises a general test mother board and a special test sub board. The invention further discloses a test method for analog-to-digital converter nonlinear parameters. The test method includes the following steps: building a slope generating function; inputting slope analog voltage into an analog-to-digital converter to be tested; capturing digital output signals of the analog-to-digital converter to be tested; counting the number of total sampling points and all stages of codes in the digital output signals; calculating the average occurrence number of the codes; and calculating differential nonlinear parameters and integral nonlinear parameters. According to the test adapter and the test method for analog-to-digital converter nonlinear parameters, the differential nonlinear parameters and the integral nonlinear parameters of the high-speed and high-accuracy analog-to-digital converter are accurately measured through a linear slope histogram and the natural statistical property of the analog-to-digital converter. The test method is higher than the conventional method and easy to operate, and reduces inaccuracy degree of measurement error to a certain extent.

Description

technical field [0001] The invention relates to the technical field of integrated circuit testing, in particular to an adapter for testing non-linear parameters of an analog-to-digital converter and a testing method. Background technique [0002] At present, the non-linear parameter testing methods of high-speed and high-precision analog-to-digital converters (ADC) mainly include: step size search method, binary search method, servo method and sine histogram method. However, the method of using step size search and binary search to find the code edge of the ADC, thereby calculating the nonlinear parameters of the ADC, for low-speed, low-precision ADCs, this method It is acceptable; however, for high-speed and high-precision analog-to-digital converters, dozens or even hundreds of samples are required for each iteration to complete a code edge. Such a test time is too long to meet the needs of batch testing. Although the servo method improves the test speed through the hardw...

AI Technical Summary

Problems solved by technology

However, the method of using step size search and binary search to find the code edge of the ADC, thereby calculating the nonlinear parameters of the ADC, for low-speed, low-precision ADCs, this method It is acceptable; however, for high-speed and high-precision analog-to-digital converters, dozens or even hundreds of samples are required for each iteration to complete a code edge. Such a test time is too long to meet the needs of batch testing

Although the servo method has improved the test speed through the hardware circuit, it is still not fast enough, and it is not easy to implement in terms of method realization.

At the same time, these methods have high requirements on the accuracy of the reference DC power supply of the instrument and equipment, and are very unsuitable for testing high-speed and high-precision analog-to-digital converters.

The sine histogram method is mainly used to measure the dynamic performance parameters of analog-to-digital converters, and it has problems such as uneven distribution of output codes and complicated implementation, so it is not suitable for testing static nonlinear parameters.

Images