Expediting analog design retargeting by design knowledge re-use and circuit synthesis: a practical example on a Delta-Sigma modulator

ABSTRACT

In the past decade or two, due to constant and rapid technology changes, analog design re-use or design retargeting to newer technologies has been brought to the table in order to expedite the design process and improve time-to-market. If properly conducted, analog design retargeting could significantly cut down design cycle compared to designs starting from the scratch. In this article, we present an empirical and general method for efficient analog design retargeting by design knowledge re-use and circuit synthesis (CS). The method first identifies circuit blocks that compose the source system and extracts the performance parameter specifications of each circuit block. Then, for each circuit block, it scales the values of design variables (DV) from the source design to derive an initial design in the target technology. Depending on the performance of this initial target design, a design space is defined for synthesis. Subsequently, each circuit block is automatically synthesised using state-of-art analog synthesis tools based on a combination of global and local optimisation techniques to achieve comparable performance specifications to those extracted from the source system. Finally, the overall system is composed of those synthesised circuit blocks in the target technology. We illustrate the method using a practical example of a complex Delta-Sigma modulator (DSM) circuit.

KEYWORDS:

• Analog and mixed-signal design
• technology retargeting
• analog design re-use
• analog design knowledge
• analog circuit synthesis
• continuous time Delta-Sigma modulators

Acknowledgement

The author would very much like to thank the reviewers for their very valuable comments and suggestions, which not only helped to improve the content and presentation of the article, but also helped the authors’ more complete analysis of the proposed method in terms of advantages, challenges and limitations.

Disclosure statement

No potential conflict of interest was reported by the authors.