9 Digital Circuit Design for Biological and Silicon Computers Matthias Függer, Manish Kushwaha, and Thomas Nowak Abstract Modern electronic computing devices profit from two far-reaching design choices: the digital abstraction of a continuous signal domain into a binary domain to tolerate noise, and the use of the complementary metal-oxide- semiconductor (CMOS) technique in gates to reduce noise and power consumption. Biological circuit design in the last two decades has been greatly inspired by the digital abstraction of electronic circuits, while still using a relatively analog machinery. With the constantly growing techniques and components available in synthetic biology, the question arises if chip design choices and other lessons learned from silicon computers can be transferred to biological designs. In this context, we discuss here the similarities and differences between the two fields concerning representation of circuits, solutions to computational problems, their implementations, and challenges. All authors contributed equally. M. Függer CNRS, LSV, ENS Paris-Saclay, Université Paris-Saclay, Inria, Saint-Aubin, France e-mail: mfuegger@lsv.fr M. Kushwaha () Micalis Institute, INRA, AgroParisTech, Université Paris-Saclay, Jouy-en-Josas, France e-mail: manish.kushwaha@inra.fr T. Nowak Université Paris-Sud, CNRS, Orsay, France e-mail: thomas.nowak@lri.fr © Springer Nature Singapore Pte Ltd. 2020 V. Singh (ed.), Advances in Synthetic Biology, https://doi.org/10.1007/978-981-15-0081-7_9 153