|vlsitechnology.org /open source cells /vtvt libraries|
Virginia Tech University has produced two standard cell libraries in 0.25µm and 0.18µm TSMC technologies. The libraries are quite recent: December 21, 2006 for the 0.25µm and November 1, 2007 for the 0.18µm. There is a home page for the libraries, but they are not freely downloadable, and have to be requested thru a web form. The licence for the libraries is quite restrictive.
Both libraries have 83 cells including 3 drive strengths for many functions.
The 0.25µm library has been drawn with the MOSIS SCN5M-DEEP rules and lambda=0.12µm. The routing pitch is 1.08µm which is 9λ and the cell height is 126λ (15.12µm) or 14 routing tracks, which makes it one of the largest libraries I know.
There are multiple drive strengths, with an X2 drive having P transistors 28λ wide and N transistors 14λ. This is the same as the wsclib, which though has a cell height of 80λ.
The basic 2-NAND gate on the right is 5 tracks wide and uses small transistors … probably 14λ for the P and 7λ for the N.
There is no information on the 0.18µm library. Probably it has been drawn with the MOSIS SCN6M_DEEP rules by modifying if necessary the 0.25µm layout. This uses lambda=0.09µm and would give a cell height of 11.34µm (126λ).
Basic 2-NAND gate in the VTVT 0.25µm standard cell library
D flip-flop in the VTVT 0.25µm standard cell library