As the electronic component supply chain grows more complex due to globalization, with parts coming from a diverse set of suppliers, counterfeit electronics have become a major challenge that calls for immediate solutions. The need for protection of chip technologies becomes greater and greater as chip designs become more valuable, and as tools for the simple extraction of the circuit from its physical instantiation become more sophisticated. Analog and mixed signal layouts are among the most complex and time-consuming designs to produce, and thus are some of the most valuable designs. Previous IC protection techniques have focused on protecting Digital IP from the overproduction, counterfeiting, and trojan insertion. However, not enough research has yet addresses the protection of Analog IP.

Addressing the above issues, Researchers at Drexel have now developed a novel key-based encryption technique to protect analog IP from reverse engineering and counterfeiting. Setting the correct biasing points in an analog circuit is critical to establishing proper operating conditions, as circuit functionality and performance are directly dependent on the set bias voltages and currents. Drexel’s key based encryption technique obfuscates the physical dimensions of the transistors used to set these optimal biasing conditions and, based on an applied key sequence, provides a range of potential biasing points. Only when the correct key sequence is applied and certain transistor(s) are active, are the correct biasing conditions set at the target node. The technique is applicable to various biasing parameters including setting the voltage or current at a node or modifying the gain of the circuit. By implementing the proposed technique on multiple analog components in the integrated circuit, the key space is increased and the overall security is further improved. The analog obfuscation technique complements existing digital logic encryption to further protect modern ICs.