projects.si2.org/openeda.si2.org Group Long Description:

NanGate FreePDK45 Generic Open Cell Library


2011-09-09 Preview the Upcoming Press Release
Read the press release from March 3, 2008.
Library Overview

The Nangate Open Cell Library is a generic open-source, standard-cell library provided for the purposes of research, testing, and exploring EDA flows. This library is purposely non-manufacturable.

Nangate has developed and donated this library to Si2 for open use. The library is intended to aid university research programs and organizations such as Si2 in developing flows, developing circuits and exercising new algorithms. In its first release the Open Cell Library contains 38 different functions ranging from buffers to scan flip-flops with set and reset. All the different cell functions come in multiple drive strength variants end up with more than 100 different cells in the library.

The library was generated using Nangate's Library Creator™ and the 45nm FreePDK Base Kit from North Carolina State University (NCSU) and characterization was done using the Predictive Technology Model (PTM) from Arizona State University (ASU). The FreePDK Base Kit is supported by Professors Rhett Davis and Paul Franzon and their research teams and is also available for download.

Because the library was generated using a non-optimized Open PDK, it was not created to be an optimized library for any real-life applications.

Benchmarking of this library against any other library makes no sense and any use for comparisons are hereby prohibited. The use of this library for commercial tool benchmarking is also prohibited.

The library will be enhanced over time based on user suggestions and requests. If you have suggestions for development of the library then please submit them to the project New Feature Request tracker. Report bugs in our Library Bug tracker and join the Library Discussion Forum to solicit help and suggestions from other library users.

Library Contents

NEW: The PDKv1.3_2010_12 release (released August 2011) of the Open Cell Library contains the following updates:
  • Improved sizing of all cells
  • Included VITAL (VHDL Initiative Towards ASIC Libraries) views
  • Included Cadence Virtuoso database
  • Added a set of low power cells
  • New IP release directory structure

The PDKv1.3_2009_07 release of the Open Cell Library contains the following updates:
  • Updated to support FreePDK v1.3 package from NCSU released March 4, 2009
  • Changed manufacturing grid size from 2.5nm to 5nm as the previous size is not supported in some P&R tools
  • Changed via definitions in Calibre rule files in order to have more realistic values out of extraction
  • Added capacitance tables (PTF and CapTbl) for wire load extraction
  • Added two corners covering temperature inversion effects (low temperature and worst low temperature)
  • Added schematic views in EDIF format
  • Added wire load tables in Liberty views
  • Added conditional rules in LEF views

The PDKv1.2_v2008_10 SP1 release of the Open Cell Library contains the following updates:
  • Updated LEF views to solve problems of vias not being created for metal 3 wires

The PDKv1.2_v2008_10 release of the Open Cell Library contains the following updates:
  • Added clock gates with and without test as new functions to the library
  • Added tabs to all filler cells
  • Updated OpenAccess views to support Cadence SoC Encounter 6.2 platform
  • Updated layouts (GDS) to ensure all ports were on grid
  • Updated LEF views to avoid issues seen with various Place & Route flows

The PDKv1.2_v2008_05 release of the Open Cell Library contains the following views:
  • Liberty (.lib) formatted libraries with CCS Timing, ECSM Timing and NLDM/NLPM data (fast, slow and typical corners)
  • Geometric library in Library Exchange Format (LEF)
  • Simulation libraries in Verilog and Spice (pre and post parasitic extracted netlists)
  • Cell layouts in GDSII
  • Schematics
  • Library databook in HTML/XML format
  • OpenAccess database containing layouts and netlists

The v1.0 20080225 release Open Cell Library contains the following views:
  • Liberty (.lib) with NLDM/NLPM
  • LEF View
  • Verilog
  • Spice netlists
  • GDSII
  • Schematics
  • Library databook in HTML/XML format