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Alliance sxlib Cell Library
The sxlib was first released in 1999. The library is supplied in a proprietary format (.ap files), but the software needed to view and edit the files is supplied free from the same source, along with a utility to convert to CIF and GDS. The .ap files are ascii which is always convenient.
The cells are 100λ tall with 40λ available for P transistors and 33λ for N ones. The metal-1 pitch is 8λ and the metal-2 pitch and above is 10λ. The cells are designed for horizontal metal-2 routing, although they can be used less efficiently with vertical metal-2.
For a 0.13µm technology, lambda=0.055µm, so the metal-2 pitch is 5.5µm which is quite large (pitch values between 0.4µm and 0.45µm are achievable in 0.13µm technology).
There are 91 cells with 2 drive strengths or more for all functions. Library timing is 0.35µm, but unfortunately the Spice parameters are not available. This web site has 0.13µm timing for 62 of the cells using publicly available Spice parameters.
Most cells make use of these available transistor sizes, so the efficiency of the library is quite good. In some cases though the parasitic capacitances are not minimised, and some transistor sizing is approximative for true high performance. But overall the library is large and fast. None of the cells uses metal-2 for crossovers.
The basic 2-XOR gate is 90λ wide compared to 64λ for the vsclib.