A Built-In Self-Test (BIST) system with non-intrusive TPG and ORA for FPGA test and diagnosis

This paper presents a BIST system with non-intrusive test pattern generator (TPG) and output response analyzer (ORA) for field-programmable gate array (FPGA) test and diagnosis. The proposed BIST system physically consists of software and hardware parts with two communication channels in between. The TPG and ORA of the BIST circuitry are in the software part while a circuit under test (CUT) is in the hardware part, respectively. One more FPGA is incorporated in the hardware part to act as an interface between the TPG, ORA and the CUT. Algorithms for FPGA test and diagnosis are also presented. Compared with embedded BIST technique, configuration numbers can be reduced without exchanging the TPG, ORA for the CUT when the proposed BIST system is applied to test an FPGA. Also, the proposed BIST system can provide good observability and controllability for the FPGA-under-test due to the proposed algorithms developed for test and diagnosis. No matter what type and array size of an FPGA-under-test is, the CUT can be tested by the proposed BIST system. The BIST system is evaluated by testing several Xilinx series FPGAs, and experimental results are provided.