Direct Transistor-level Layout for Digital Blocks

Gopalakrishnan, Prakash; Rutenbar, Rob A.

ISBN 10: 1402076657 / ISBN 13: 9781402076657

Editore: Springer-Verlag New York Inc., 2004

Riguardo questo articolo

Proposes a direct transistor-level layout approach for small blocks of custom digital logic as an alternative that accommodates demands for device-level flexibility. Useful for CAD tool and circuit designers, this approach aims to capture essential shape-level optimizations and incorporates timing optimization during layout. Num Pages: 125 pages, biography. BIC Classification: TJFC. Category: (G) General (US: Trade); (P) Professional & Vocational; (U) Tertiary Education (US: College). Dimension: 232 x 156 x 9. Weight in Grams: 377. . 2004. Hardback. . . . .

Codice articolo V9781402076657

Dati bibliografici

• Titolo: Direct Transistor-level Layout for Digital Blocks
• Editore: Springer-Verlag New York Inc.
• Data di pubblicazione: 2004
• Lingua: Inglese
• ISBN 10: 1402076657
• ISBN 13: 9781402076657
• Rilegatura: Rilegato
• Condizione: New

Descrizione articolo

Riassunto

Cell-based design methodologies have dominated layout generation of digital circuits. Unfortunately, the growing demands for transparent process portability, increased performance, and low-level device sizing for timing/power are poorly handled in a fixed cell library.
Direct Transistor-Level Layout For Digital Blocks proposes a direct transistor-level layout approach for small blocks of custom digital logic as an alternative that better accommodates demands for device-level flexibility. This approach captures essential shape-level optimizations, yet scales easily to netlists with thousands of devices, and incorporates timing optimization during layout. The key idea is early identification of essential diffusion-merged MOS device groups, and their preservation in an uncommitted geometric form until the very end of detailed placement. Roughly speaking, essential groups are extracted early from the transistor-level netlist, placed globally, optimized locally, and then finally committed each to a specific shape-level form while concurrently optimizing for both density and routability.
The essential flaw in prior efforts is an over-reliance on geometric assumptions from large-scale cell-based layout algorithms. Individual transistors may seem simple, but they do not pack as gates do. Algorithms that ignore these shape-level issues suffer the consequences when thousands of devices are poorly packed. The approach described in this book can pack devices much more densely than a typical cell-based layout.
Direct Transistor-Level Layout For Digital Blocks is a comprehensive reference work on device-level layout optimization, which will be valuable to CAD tool and circuit designers.

Contenuti

Circuit Structure and Clustering.- Global Placement.- Detailed Placement and Layout Results.- Timing-Driven Placement.- Conclusion.