Electronic physical unclonable functions
View Patent ↗An electronic asymmetric unclonable function applied to an electronic system being evaluated includes an electronic system and an AUF array electronically associated with the electronic system. The AUF array includes a plurality of non-identical cells. Each of the non-identical cells includes a test element representing a characteristic of the electronic system being evaluated and a measurement device evaluating the test element. A comparison unit processes an output of the measurement device to provide a multi-bit output value representing a magnitude of differences.
1. An electronic asymmetric unclonable function applied to an electronic system being evaluated, comprising:
the electronic system comprising an integrated circuit;
an asymmetric unclonable function array electronically associated with the electronic system, the asymmetric unclonable function array including a plurality of non-identical cells of different constructions including different delay or different structural elements, each of the non-identical cells including a test element comprising an oscillator representing a characteristic of the electronic system being evaluated and a measurement device comprising a binary counter evaluating the test element to provide an output value, the test element of each of the non-identical cells being composed of delay elements and routing structures, wherein each test element of the plurality of non-identical cells incorporate different arrangements of delay elements and routing structures, and wherein a time interval over which the measurement device evaluates operation of the test element is adjusted based on temperature, voltage or age; and
a comparison unit processing output values of the measurement device of each of the plurality of non-identical cells to provide a multi-bit output value for each test that represents a magnitude of differences between the plurality of non-identical cells such that the multi-bit output value is applied in comparing integrated circuits to identify differences in the integrated circuits for identification of counterfeit or modified electronics.
2. The electronic asymmetric unclonable function according to claim 1 , wherein the measurement device is the binary counter.
3. The electronic asymmetric unclonable function according to claim 1 , wherein the test element of each of the non-identical cells is the oscillator.
4. The electronic asymmetric unclonable function according to claim 3 , wherein the binary counter of the non-identical cells shares an enable signal allowing the binary counter of each of the non-identical cells to evaluate the operation of the respective oscillators over a specific period of time.
5. The electronic asymmetric unclonable function according to claim 3 , wherein the oscillator is a ring oscillator.
6. The electronic asymmetric unclonable function according to claim 1 , wherein the time interval over which the measurement device evaluates operation of the test element is adjusted based on environmental compensation.
7. The electronic asymmetric unclonable function according to claim 6 , wherein the non-identical cells include at least one reference cell and a plurality of evaluation cells.
8. The electronic asymmetric unclonable function according to claim 7 , wherein the at least one reference cell determines the time interval.
9. The electronic asymmetric unclonable function according to claim 8 , wherein the reference cell includes a comparator and a signal generating device.
10. The electronic asymmetric unclonable function according to claim 9 , wherein only the reference cell includes a comparator and a signal generating device.
11. The electronic asymmetric unclonable function according to claim 1 , wherein the time interval over which the measurement device evaluates operation of the test element is adjusted based on scaling such that one evaluation output values is subtracted from another evaluation output value to scale data.
12. The electronic asymmetric unclonable function according to claim 1 , wherein the test element of the non-identical cells includes an arithmetic function.
13. The electronic asymmetric unclonable function according to claim 1 , wherein the test element of the non-identical cells includes a memory device.
14. The electronic asymmetric unclonable function according to claim 1 , wherein the test element of the non-identical cells includes a diode.
15. The electronic asymmetric unclonable function according to claim 1 , wherein the test element of the non-identical cells includes a separate integrated circuit.
16. The electronic asymmetric unclonable function according to claim 1 , wherein the test element of the non-identical cells includes an amplifier.
17. The electronic asymmetric unclonable function according to claim 1 , wherein the test element of tile non-identical cells includes optical or physical devices.
18. The electronic asymmetric unclonable function according to claim 1 , wherein the measurement device includes a volt meter or voltage measuring device.
19. The electronic asymmetric unclonable function according to claim 1 , wherein the measurement device includes a current measuring meter or device.
20. The electronic asymmetric unclonable function according to claim 1 , wherein the asymmetric unclonable function array is implemented as a programmable logic device.