Abstract: In terms of the regularity and peculiar feature of a PLA's circuit structure,the paper proposes a converse testable design scheme,where outputs of the PLA's circuit are converted into inputs, and OR array into AND array by an available method,and at column the test results are observed.The results through evaluating the scheme show that under the condition of ensuring high fault coverage,the scheme not only decreases the number of the test vectors by applying an universal test set,but substantially thrifts the extra hardware overhead.