An integrated circuit (IC) measures uncertainties in a first signal. The IC comprises a programmable delay circuit to introduce a programmable delay to the first signal to generate a first delayed signal. The IC further comprises a digital delay line (DDL) comprising a first delay chain of delay elements having input to receive the first delayed signal. The DDL further comprises a set of storage elements, each storage element having an input coupled to an output of a corresponding delay element of the first delay chain, and an output to provide a corresponding bit of a digital reading. The DDL additionally comprises a decoder to generate a digital signature from the digital reading and a controller to iteratively adjust the programmed delay of the programmable delay circuit to search for a failure in a resulting digital signature.