The research of extracting and verifying equivalent function for logic unknow chip

The equivalent extraction of unknown logical chip is a new technology in the chip test and malfunction inspection. From the traditional design flow of logical chips, the expression form of logical chips in different design phases was abstracted, which thereby proves theoretically the feasibility of the transformation from work waveform to chip logical expression. With emphasis laid on the qualification and basic process of equivalent transformation of chip´s logical function and the detailed method of implementation and design flow presented, the paper designed and then used the EDA stimulation tool to verify the extracted equivalent logical function. By comparing the working waveform of target chips, the stimulation verification module can verify the consistence of logical function as well as check the existence of the function flaw in the target chip.