Breaking Analog Biasing Locking Techniques via Re-Synthesis

Abstract

We demonstrate an attack to break all analog circuit locking techniques that act upon the biasing of the circuit. The attack is based on re-synthesizing the biasing circuits and requires only the use of an optimization algorithm. It is generally applicable to any analog circuit class. For the attacker the method requires no in-depth understanding or analysis of the circuit. The attack is demonstrated on a bias-locked Low-Dropout (LDO) regulator. As the underlying optimization algorithm we employ a Genetic Algorithm (GA).