Trends in Analogic Design: Highly Reconfigurable Filters, Performance Optimization and IP Protection

Abstract

The continuous technology scaling and rapid growth of applications involving a vast and diverse network of interconnected devices increase analog integrated circuit (IC) design complexity. This work addresses three main trends of analog IC design: highly reconfigurable power-efficient analog circuits, automatic IC design for performance optimization, and analog IP protection against security threats.

The first part of this dissertation discusses the synthesis and design methodology of high-order and frequency-tunable low-pass active-R filter architectures for multi-standard wireless applications. Active-R filters use the inherent integrator-like behavior of amplifiers to realize their frequency response. The main advantages of this type of filter are high-frequency performance and a low integrated area since the only capacitor they require is the Miller capacitor used in internally compensated amplifiers. In this work, amplifiers with configurable unity-gain frequencies enable the continuous tuning of active-R filters. Three different filter architectures realize a fifth-order Butterworth prototype tunable in the 1--50~MHz frequency range.

The second part of this dissertation discusses the development of a computationally low-cost surrogate model for multi-objective optimization-based automated analog IC design. The surrogate has three main components: a set of Gaussian process regression models of the technology's parameters, a physics-based model of the MOSFET device, and a set of equations of the performance metrics of the circuit under design. The surrogate model is inserted into two different state-of-the-art optimization algorithms to prove its flexibility. The efficacy of our surrogate is demonstrated through simulation validation across process corners in three different CMOS technologies, using three representative circuit building-blocks that are commonly encountered in mainstream analog/RF ICs.

Finally, this dissertation presents an overview of analog IP security, including the threat models, protection techniques, and reported attacks. A novel Schmitt-trigger based key provisioning technique is proposed for increasing the security level of existing IP protection techniques. This approach has a very small area overhead that remains constant and independent of the key size. Moreover, it consumes power only at power-up.