Accumulator-Based Testing Scheme for DSP Data Path

Based on accumulator, a general testing approach for DSP data path and algorithms suitable for the scheme to supply test patterns efficiently are proposed. For the scheme, DSP data path is classed into orders according to structural similarity, and then the building modules with identical connections in one order are partitioned into one layer. Finally, testing of the data path is performed under test-per-scan and in order and layer. The results of IIR filters data paths test based on the scheme show that the scheme has high coverage of multiple stuck-at faults and can detect all single stuck-at faults in DSP data path. The scheme is good in generality and can be performed at-speed with little additional hardware overhead due to reuses of part registers and adders in original circuit. It needs short test time. It needs only 447 clock periods to test the data paths of 8 order IIR filters which adopts array multipliers and adders/subtractors with 4-bit contiguous subspace if the word widths are 8 bits.