Low_Power/README

Nangate 45nm Low Power Open Cell Library
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The Nangate Open Cell Library is an open-source, standard-cell library provided for the purposes of testing and exploring EDA flows.

Nangate has developed and donated this library to Si2.org 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 
Low Power Open Cell Library contains always-on cells, isolation cells, level shifters and power-switches. All 
the different cell functions come in multiple drive strength variants. 

The Low Power Open Cell library contains the following cells types:

    * Always-on cell 
      A special cell located in a switched-off domain, and whose power supply is continuous even when the power supply for the 
      remaining logic in the power domain is off.

    * Isolation cell
      Logic used to isolate signals between two power domains where one is switched on and one is switched off. The most common 
      usage of such cell is to isolate signals originating in a power domain that is being switched off, from the power domain 
      that receives these signals and that remains switched on.

    * Level-shifter cell
      Logic to pass data signals between power domains operating at different voltages.

    * Power-switch (header) cell
      Logic used to connect and disconnect the power supply from the gates in a power domain.


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 library will be enhanced over time based on user suggestions and requests. If you have suggestions for development of 
the library then please fill out the request form you can find at www.opencelllibrary.org with your suggestions.

The Low Power Open Cell Library contains the following views:

    * Liberty (.lib) with NLDM/NLPM, CCS Timing and ECSM Timing data
    * LEF View
    * Verilog(R)
    * VITAL (VHDL Initiative Towards ASIC Libraries)
    * Spice netlists (pre and post extraction)
    * GDSII
    * Schematics
    * Library databook in HTML/XML format
    * OpenAccess library databases with layouts and netlists

See the LICENSE file for information on license terms.

Revision History:
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Version v2010_12 (released August 2011)
- Initial release of the Low Power Open Cell Library