BIST of delay faults in the logic architecture of symmetrical FPGAs

In this paper, we propose a BIST scheme for exhaustive testing all delay faults in the logic architecture of symmetrical FPGAs. This scheme is applicable in a Manufacturing-Oriented Test (MOT) context. Our technique enables the detection of delay faults in the logic architecture and consists in chaining the logic cells in a specific way. The test of all the delay faults can be done with a reduced test sequence and does not require expensive ATE. To illustrate its feasibility, this BIST approach has been implemented in a VIRTEX FPGA from XILINX Inc.