According to one aspect of the invention, a circuit for determining the location of a defect in an integrated circuit is described. The circuit comprises a conductor extending from a first node to a second node and a test signal driver coupled to the first node of the conductor. The test signal driver receives a test signal using a first clock signal, while a plurality of detector circuits coupled to the conductor between the first node and the second node to detect an output at the plurality of nodes using a second clock signal. According to other embodiments, circuits for determining the location of a defect in a programmable logic device are disclosed. Finally, various methods for determining the location of a defect in an integrated circuit are described.