## 7 Conclusions  
In this paper, we introduced a holistic evaluation platform for an analog-based Physical Unclonable Function (PUF), covering the full software and hardware implementations. We fabricated 30 PUF cores and evaluated their PUF responses under different operating conditions, such as changing ambient temperatures and varying supply voltages. Due to the additional measurement capabilities of our evaluation platform, we could trace PUF response bit flips that occurred on the digital level back to the analog voltage level. Furthermore, we evaluated the bit errors that appear over time for each single PUF core. The experimental results of the fabricated PUF core instances show superior security metrics, such as an average reliability of 99.20%, a uniqueness value of 48.84%, a uniformity of 45.60%, and low bit error rates. In addition, our PUF platform offers the unique benefits of accessibility and bitwise understanding on analog and digital signal levels. These features make the proposed design highly suitable as an analog PUF test platform for hardware-centric security. In general, analog PUF designs as proposed in this work are promising candidates for the use in application fields where devices underlie strict design or performance constraints, such as in the IoT. Conceptualization, all; methodology, A.S. ([PERSON]) and L.Z. ; software, L.Z. ; validation, A.S. ([PERSON]) and L.Z. ; formal analysis, A.S. ([PERSON]) and L.Z. ; investigation, A.S. ([PERSON]) and L.Z. ; resources, all; data curation, A.S. ([PERSON]) and L.Z. ; writing--original draft preparation, A.S. ([PERSON]) and L.Z. ; writing--review and editing, all; visualization, A.S. ([PERSON]) and L.Z. ; supervision, A.S. ([PERSON]), M.B.T., and J.-A.-H.; project administration, A.S. ([PERSON]), M.B.T., and J.-A.-H.; funding acquisition, [PERSON] ([PERSON]), M.B.T., and J.-A.-H. All authors have read and agreed to the published version of the manuscript. This research was funded by the Ministry of Science, Research, and Arts of the state of Baden Wuerttemberg, Germany. This work was supported in part by the Ministry of Science, Research, and Arts of the State of Baden Wuerttemberg, Germany through the Modellierung, Entwurf, Realisierung und Automatisierung von gedruckter Elektronik und ihren Materialien (MERAGEM) Doctoral Program and in part by the Institute of Reliable Embedded Systems and Communication Electronics (ivESK), University of Applied Sciences Offenburg, Germany. The article processing charge was funded by the Ministry of Science, Research, and Arts of the State of Baden Wuerttemberg, and the Offenburg University of Applied Sciences in the funding program Open Access Publishing. The authors declare no conflict of interest. The following abbreviations are used in this manuscript: \begin{tabular}{l l} ADC & Analog-to-digital converter \\ BA & Buffer amplifier \\ CMOS & Complementary metal-oxide-semiconductor \\ CRP & Challenge-response pair \\ DAC & Digital-to-analog converter \\ DC & Direct current \\ DEMUX & Demultiplexer \\ HD & Hamming distance \\ IC & Integrated circuit \\ ID & Identifier \\ IoT & Internet of things \\ MUX & Multiplexer \\ NMOS & Negative channel metal-oxide-semiconductor \\ PCB & Printed circuit board \\ PUF & Physical unclonable function \\ RO & Ring oscillator \\ \end{tabular}   
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