A Discussion on Test Pattern Generation for FPGA—Implemented Circuits

The objective of this paper is to generate a Application-Oriented Test Procedure to be used by a FPGA user in a given application. General definitions concerning the specific problem of testing RAM-based FPGAs are first given such as the important concept of 'AC-non-redundant fault.' Using a set of circuits implemented on a XILINX 4000E, it is shown that a classical test pattern generation performed on the circuit netlist gives a low AC-non-redundant fault coverage and it is pointed out that test pattern generation performed on a FPGA representation is required. It is then demonstrated that test pattern generation performed on the FPGA representation can be significantly accelerated by removing most of the AC-redundant faults. Finally, a technique is proposed to even more accelerate the test pattern generation process by using a reduced FPGA description.