A salient feature of complex systems is their inherent robustness against poor and fluctuating characteristics of constituent elements, systematic offsets in parameter values, environmental changes, noise, and other such fluctuations. In spite of such unreliable, poorquality, and highly variable elements, complex systems generally exhibit high-quality behavior as a whole. In this paper, we exploit this inherent robustness of complex systems to create a compact and efficient realization of a hardware system for exponential chaotic tabu search. We start from a synchronous exponential chaotic tabu search algorithm and develop a novel partial-update exponential chaotic tabu search algorithm. The proposed algorithm is suitable for a large-scale analog/digital hybrid hardware implementation. In addition, a hardware system architecture suitable for the partial-update exponential chaotic tabu search is proposed, and a switched-current chaotic neuron integrated circuit dedicated to the proposed system architecture is also designed. We investigate the feasibility of implementing the digital part of the system with a field-programmable gate array.Key Words: complex systems, analog/digital hybrid hardware, quadratic assignment problems, chaotic tabu search, chaotic neuron, nonlinear analog integrated circuits Partial-update exponential chaotic tabu searchThe following summarizes the modified SECT-MA-woW/Eta discussed above, which we refer to as the "partial-update exponential chaotic tabu" (PUECT) search. PUECT:PU-1 We quasi-randomize matrices A and B by applying row and column substitution matrices to them several times. PU-2We use U = 5, and set AF R ≈ 10-15% by tuning the value of θ ζ . PU-3A group of 50 neurons is updated simultaneously. PU-4We select the first 5 fired neurons in ascending order of neuron index. PU-5The current permutation p current is updated with the selected 5 neurons resulting in 5 different permutations: p 1 , p 2 , . . . , p 5 . PU-6We select the permutation p M from the resulting 5 permutations that gives the largest value of ΔF p M (t). If ΔF p M (t) > 0, then p current is replaced with p M . Otherwise, we keep p current .