MOJITO: Structural Synthesis

MOJITO is a tool for analog circuit topology selection / topology design (synthesis). It reconciles automatic creative design with manual expertise.

  • Inputs: a hierarchical library of analog building blocks (pre-specified), having >100K possible topologies
  • Action: Searches ("synthesizes") possible topologies and sizings, with SPICE in the loop. Multi-objective, device operating constraints. Operating-point driven approach to sizing.
  • Returns: a set of sized topologies that approximate a performance tradeoff curve. 

Once just one MOJITO run is done at a process node, the results are stored as a db for future queries by other designers. Therefore MOJITO supports a "specs-in sized-topology-out" workflow with immediate turnaround.

The original MOJITO project work was 2005-2008, as part of my PhD at KU Leuven. Since then, I keep finding myself coming back to it in the context of hierarchical design. E.g. 2020 blog post on Wright brothers, 2018 blog post. 

Open-source code:

1. Basic version, simplest, most stable: https://github.com/trentmc/mojito

2. Faster, variation-aware, bigger library: https://github.com/trentmc/mojito_r_tapas

Representative papers:

T. McConaghy, P. Palmers, G.G.E. Gielen, and M. Steyaert, Variation-aware structural synthesis of analog circuits via hierarchical building blocks and structural homotopy, IEEE Transactions on Computer-Aided Design 28(9), Sept. 2009, pp. 1281–1294. [PDF]

P. Palmers, T. McConaghy, M. Steyaert, and G.G.E. Gielen, Massively multi-topology sizing of analog integrated circuits, in Proc. Design Automation and Test in Europe (DATE), March 2009. [PDF]

T. McConaghy, P. Palmers, G.G.E. Gielen, and M. Steyaert, Automated extraction of expert knowledge in analog topology selection and sizing, in Proc. Intern. Conference on Computer-Aided Design (ICCAD), San Jose, November 2008. [PDF]

Book:

T. McConaghy, P. Palmers, P. Gao, M. Steyaert, and G.G.E. Gielen.  Variation-Aware Analog Structural Synthesis: A Computational Intelligence Approach.  Springer, 2009, ISBN 978-9048129058.[Springer] [Amazon]