I have a question about PDK integrity

Hi!

How can the CDF file be linked to each symbol? In other words, if I
want to create a complete symbol, create some parameters on it, and
create the corresponding CDF file, how can this file be automatically
linked with the created schematic symbol?

I know that If I put the symbol in a library, then the CDF file is
loaded from CIW, it'll be linked, but we didn't do that when we were
installing the PDK we currently have, all what we did is to define the
path to PDK library in the ~/cds.lib!

Anybody can help?
Thanks,
Joe

 

Joe,

Well, CDF is actually stored in a cell property called cdfData (do
RMB->properties in the library manager over the cell, and you'll see it). This
is stored in the binary prop.xx file (in CDB) or data.dm (in OpenAccess).

The "CDF file" you are referring to is presumably the ASCII source file you're
using to create the CDF? I don't really know, because there's no such thing as a
"CDF file"... so you probably need to elaborate on your description.

Regards,

Andrew.

 

Joe,

The foundry who did provide the PDK have the 'ASCII' CDF source files.
These source files are not in the PDK though.
The ASCII CDF file header defines the libName/cellName of the target
cellView. So when this CDF file is loaded into Cadence, it would be
compiled as binary into the prop.xx of that particular libName/
cellName as explained by Andrew. If you want to fetch the original
ASCII CDF file, then you could dump it using the cdfDump skill
function. Search this function in the CDF doc or this forum to know
more about its syntax. Many people have already given examples about
it in previous posts.

Regards,
Riad.

 

Thanks a lot Andrew/Riad..

I was wondering about how to release a PDK-like format (i.e. package)
from library of components (symbol, schematic, verilog-a, ... and
other views) in addition to ASCII CDF files..

When I look at the PDK we've, I can't see ASCII CDF files as Riad
mentioned.

In other words, how can to package PDK from library+ASCII CDF file?

Is there other files must be packaged/compiled together with them in
the PDK? (e.g. callbacks file, SKILL PCELLs, ...??)

BR, Joe

 

So you don't need to ship ASCII CDF files, as these are part of the
prop.xx/data.dm database files, as said earlier.

If you use (the dreaded) CDF callbacks (see various posts before talking about
the "dangers of CDF callbacks", as well as my sourcelink solution on this), then
the code for these would need to be in the PDK and loaded (typically from the
library's libInit.il file). Often the code is compiled into a context file or an
encrypted SKILL file to reduce the chance of tampering.

For pcells, the code can be entirely stored within the layout cellView database
of the pcell, if it's just a single definition which is calling no user-defined
functions. The code for any user-defined functions would also need to be
included in the PDK (and loaded from the libInit.il in the pcell library).

Regards,

Andrew.

 

Thanks again!

What does libInit file contains? Which syntax?

Is it the one responsible for compiling source files to PDK package
like the make file?

Can you give me example for libInit file?

BR, Joe

 

It's a SKILL file (libInit.il) which lives inside a library. The first time a
library is accessed, the file is loaded. Consequently you can use it to load any
other SKILL code, or define any settings (such as envSetVal() calls) which are
specific to that library.

For example, even analogLib in the Cadence IC installation has a libInit.il :


<ICinstDir>/tools/dfII/etc/cdslib/artist/analogLib/libInit.il

Regards,

Andrew.