A DFT technique for low frequency delay fault testing in high performance digital circuits

This paper presents a DFT (design-for-testability) technique for delay fault testing of high performance, dynamic CMOS circuits. A high performance, delay fault testable, 16 bit adder is designed in 0.18 μm CMOS technology. Simulations for the adder demonstrate that this technique can detect delay faults greater than 35 ps and improves delay fault detection capability. It also allows at least 10× reduction in test mode clock frequency. Furthermore, the proposed method is capable of providing delay fault diagnostics. However, the proposed DFT technique increases delay by 8.6% with minimal power penalty.