Simulation of Analog and Mixed-Signal Circuits

The end of the twentieth century saw a considerable evolution in integrated circuit manufacturing technologies, mainly due to market pressure for electronic communication circuits. The beginning of the 21st century is witnessing the same trend, with the emergence of connected objects, mobility-related applications, embedded systems (particularly in the automotive sector), mass data processing and medical devices. For circuit designers, this means reducing time-to-market, while at the same time satisfying demands for increased performance (reduced consumption, weight, size and cost). Added to these end-user constraints are problems of safety (aviation, automotive), connectivity and adaptation to a growing number of standards (WLAN (Wireless Local Area Network), Bluetooth, Wi-Fi (Wireless Fidelity)...). The result is an explosion in the complexity and size (in terms of number of transistors) of integrated circuits. To cope with these constraints, microprocessors, memories, analog and digital signal processing, interface circuits, operating systems, radio frequency components, etc. are integrated on the same SoC (System on Chip) chip or in the same SiP (System in Package) package.

Since time-to-market is a crucial success factor, these highly complex systems have to be designed, tested and validated in a reliable way. As manufacturing costs are very high, multiple attempts cannot be tolerated.

Players in the EDA (Electronic Design Automation) market provide integrated circuit manufacturers with design and verification flows that combine methodologies, software and hardware to meet the above-mentioned requirements.

One of the key elements of these two streams is the electrical simulator with mixed abstraction levels, mixed signals and RF (radio frequency). We'll call it simply: AMS/RF simulator for Analog Mixed Signal/RF. It will need to be able to support higher and higher levels of abstraction (with technology choices postponed as long as possible), and to take into account ever finer electrical details (power supply connections, for example) in order to respond to new technologies. At the same time as the scale of abstraction is stretching in both directions, other fields, other than electrical and thermal, also need to be taken into account: mechanics, optics, biology...

The aim of this article is to present the circuit simulator market and show how it meets the challenges described above, and to provide the reader with a basic understanding of how they work and how to use them.

A glossary of terms is provided at the end of the article.