About Matt Clapp's mosisLib

Instead of using width, length specified in microns, you specify width, length in units of lambda. That way, you can copy your library that instances mosisLib, change the global library 'lambda' CDF parameter, and automatically your schematics reflect your new process lengths and widths.

For the whole scheme to work:

1. Untar the mosisLib library and add it to your 'cds.lib' file.
   • Use the command 'tar -vxzf mosisLib.tar.gz' in the directory where all of your cadence library directories are kept. This will create the directory 'mosisLib' which contains the mosisLib library.
   • Then, modify the file "cds.lib" to have a new entry. The new line should be 'DEFINE mosisLib {directory}/mosisLib', where {directory} is the path of the directory containing your mosisLib directory. Look at the other lines in cds.lib for examples. You may have to add the line 'UNDEFINE mosisLib' before this definition to undefine a previously-defined mosisLib library.
2. Create a CDF variable "lambda" for your library (not for mosisLib itself.)
   • In the CIW, go to Tools->CDF->Edit...
   • Select 'library' and type the name of your library.
   • Also select 'Base' for the type of variables you will be modifying.
   • Finally, add a variable called "lambda" and set it to your lambda size, in meters. (so for lambda=0.35um, you would set your lambda variable to 3.5e-7)
3. Don't change existing analogLib instances to mosisLib by simply changing their properties sheet 'Library' entry. This will cause property values that shouldn't be changed in the mosisLib cell to have your old analogLib property values, messing a lot of stuff up. Make a new mosisLib instance and write in the width, length, values by hand.

• For some reason, Cadence analog simulation doesn't seem to like netlisting a schematic with a mosisLib instance in the top level. It gets confused about the lambda parameter and tries to make it a simulator variable. For simulation, you need to instance your cell in another schematic that doesn't contain any mosisLib transistors in the top level.
• mosisLib displays width on top of length for MOS transistors. This is really how things should be, but if you're used to the stupid Cadence way of seeing length displayed on top of width, you'll have to mirror the transistor if you still want this broken behavior. mosisLib does put a "W" next to the width, and a "L" next to the length, so things aren't really that difficult to understand anyway.