Stability-enhanced physically unclonable function circuitry

摘要

A Physically Unclonable Function circuit may include precharge circuitry that precharges an output. The precharge circuitry may include transistors of a first type such as N-type or P-type. Circuitry having only transistors of a second, different type may be coupled to the output. The circuitry may produce a signal at the output based on variations between the transistors of the second type. The circuitry may include first and second circuits such as first and second transistors of the second type that are cross-coupled. While the circuitry is producing the signal at the output, the precharge circuitry or any transistors not of the second type may be disabled or electrically disconnected from the output. In this way, the stability over time of the Physically Unclonable Function circuit may be improved, because only variations associated with transistors of the second type may be used in producing the signal.

主权项

1. Circuitry including a plurality of different circuit element types, the circuitry comprising:
an output; and first and second circuit elements of a given circuit element type that are coupled to the output, wherein the circuitry measures variations between the first and second circuit elements based only on respective currents drawn by the first and second circuits of the given type, and wherein the circuitry produces an output signal at the output having a value that is based on the respective current drawn by one of the first and second circuit elements.