Reconfigurable PETPG for External Testing of Digital Circuits

Abstract

In this paper, the application of the board-level external testing using the pseudo-exhaustive testing (PET) was explored. The new design approach to reconfigure the hardware of the pseudo-exhaustive test pattern generator (PETPG), based on the permutated convolved linear feedback shift register/shift register (LFSR/SR), is developed. The permutated convolved LFSR/SR is considered a superset of all previously published output-specific PETPGs in the PET with low test application time (TAT). The PET segments digital circuit-under-test (CUT) into several output cones. The proposed test system can stimulate all combinational hard faults in each output cone using the reconfigured PETPG without the need of the fault simulator, and to compact test responses of digital circuits for signature generation. The simulation results using some digital circuits, compared to previously published works, illustrate the effectiveness of the presented test approach to detect target faults with reduction of TAT.