Systems and methods for providing reliable physically unclonable functions

A device configured to provide a physically unclonable function (PUF) value, comprising:

• a plurality of PUF cells, each configured to provide a PUF contribution to the PUF value, each of the PUF cells comprising:
• a first transistor having a gate controlled by a first control line, a first terminal connected to a first signal line, and a second terminal connected to a common node;
• and
• a second transistor having a gate controlled by a second control line, a first terminal connected to a second signal line, and a second terminal connected to the second terminal of the first transistor;
• a sense amplifier configured to determine a signal level difference between the first and second signal lines to determine a PUF cell value;
• and
• a control signal generator configured to provide signals to the first control line and the second control line in a synchronized manner to identify unusable cells based on PUF cell value changes.

A non-transitory computer-readable medium encoded with instructions for commanding one or more data processors to execute steps of a method of determining a reliability of a physically unclonable function (PUF) cell of a device, the steps comprising:

• providing a first signal to a first branch of a PUF cell and a second signal to a second branch of the PUF cell, the first and second signals being provided in synchronization;
• determining a base PUF cell value based on an output of the PUF cell produced by the first signal and the second signal;
• providing a third signal to the first branch and a fourth signal to the second branch, the third signal and fourth signal being provided in series;
• determining a stressed PUF cell value based on an output of the PUF cell produced by the third signal and the fourth signal;
• and
• determining that the PUF cell is unusable based on a difference between the base PUF cell value and the stressed PUF cell value.