Testing data compression and decompression method based on ortho-position exclusive or operation

Abstract

The invention aims to deal with overlarge testing data number to provide a testing data compression and decompression method based on ortho-position exclusive-or operation, and the testing data compression and decompression method can reduce the partition number and increase the shortest run length by using a ortho-position exclusive-or method to combine consecutive 01 or 10 sequences into a codeword, wherein the consecutive 01 or 10 sequences are respectively sued as one codeword of one run; and experimental results show that the compression ratio is further improved. Through the decoding analysis, additional hardware overhead of a decoding structure of the method is less, and the method is independent of a circuit being tested, so that the method has excellent ratio of compression rate to hardware overhead.

Description

technical field [0001] The invention relates to an airport circuit test method, in particular to a test data compression and decompression method. Background technique [0002] Accompanied by the vigorous development of integrated circuit technology, the amount of SoC test data increases sharply. The sharp increase of test data will cause the storage capacity and transmission bandwidth of ATE to become the bottleneck of the test. The test data compression technology reduces the amount of data that needs to be stored and transmitted by compressing the original test set, so it is a very effective method to solve this problem. [0003] The run-length-based encoding method is a very cost-effective type of test data compression technology. It uses relatively small hardware overhead in exchange for a relatively high compression rate. Golomb encoding, FDR encoding, and AFR encoding are all based on run-length encoding. Domestic Liang Huaguo The alternating and continuous length co...

AI Technical Summary

Problems solved by technology

Among them, the Golomb code and the FDR code only encode the 0-run, and do not encode the continuous 1, so the compression rate of the undifferentiated test vector is not high; the AFR code encodes the 0-run and 1-run at the same time, so its compression rate is lower than Golomb codes and FDR codes have been improved; alternate and continuous length codes encode alternating sequences and continuous sequences alternately, and insert separators between them if alternate sequences or continuous sequences appear at the same time, so the encoding method is not flexible enough; mixed constant change The length of the long code code prefix is ​​determined by the parameter k. Once k is determined, the length of the prefix of all groups is determined. In order to obtain a better compression rate, the value of k must be determined repeatedly.

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