New algorithms for placement and routing of custom analog cells in ACACIA

KOAN and ANAGRAM II, novel analog placement and routing tools in the CMU ACACIA system are presented. Together, these tools support a more general model of analog layout than conventional analog macrocell systems. KOAN dynamically merges devices, supports complex symmetry constraints, and automatically generates well and bulk contacts. ANAGRAM II routes arbitrary-width wires, and supports over-the-device and symmetric differential wiring. Both tools have more support for interactive use than their predecessor, the original ANAGRAM system. Preliminary results are encouraging.<<ETX>>

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