Study On The Testing Technologies Of The Analog-to-Digital Converters

IC design is developing toward ultra-large-scale integration, high-speed, high stability, low power consumption with the rapid development of electronic science and technology. It is necessary to improve the performance of the integrated circuits, reduce production costs for meeting a variety of applications. IC testing is an essential part of the IC design. Not only is it paid the attention by people, but also the growing share of the all cost according to the current situation. The testing session do not give the product increased functionality, but from the view of the entire IC design, the product is unlikely to enter to the market, and certainly will not be accepted by the market that have not been tested. Currently, the testing aspects of the integrated circuits have accounted for30%of the cost of the chips. And this trend is still expanding. Now more and more designers are required to consider the chip testable early in the integrated circuit design. We can see the importance of the testing. To be specific, the testing of the analog-to-digital conversions is also important. The ADCs only have passed the testing that can determine the performance parameters of the analog-to-digital conversions and the working environment. Therefore, exploration and research of the integrated circuit testing methods is very necessary. This article focuses on testing technologies of the analog-to-digital conversions.First, that has been analyzed what are the existing analog-to-digital conversion testing techniques. Several frequently used methods have been introduced, such as code density histogram test method, fast Fourier transform method. Especially, this article has made the detailed comparison of their algorithms, discussed the advantages and disadvantages of them, and analyzed the mainstream testing algorithms from the theoretical. Then, the article selected fast Fourier transform algorithm by comparison for actual testing validation. Not only facilitating the operation, but also the article has considered that which can better reflect the performance of the chip. This selection of the test chip is ADC0804. ADC0804conversion rate is low, but its application is a wide range. It is still very representative to choose to test ADC0804. The actual test is divided into three parts. First, ADC0804Data Sheet was viewed. The article set up the simulation circuit for being familiar with the chip performance with proteus software. Then, the article designed schematic with the Altium Designer software. After verifying it correct, the article designed PCB layout and made PCB testing board. Finally, the article built a testing environment with the laboratory equipments. This article tested the ADC0804and entered the testing data into a computer. The article processed the chip testing data with matlab software, and finally got the expected testing result.