hi  
i want to design the 1GHz 6bit ADC in TSMC 180nm RF PDK. using the HSPICE simulator.  
my question=> if i use TSMC 180nm RF hspice.and if i include this file into my HSPICE simulator and start the design of that ADC '> can i design this way correctly.???  
because i am having the HSPICE simulator which is not the rf simulator.  
so by adding the RF model file would i be able to design the circuit correctly.  
if the answer is no then my assumption is that in the 1Ghz adc i dont need to run the s parameter analysis or pss or pxf analysis.  
so i can do the design by usign the Hspice .  
plz revert back..  
regards

Hi manisms,
                  you probably know this by now, but I contribute it for the benefit of others reading this "after the fact":

The PDK should contain a file or group of files with the extension .l or .lib (maybe .txt) - open them with wordpad or notepad and yhou will see that they are in fact Hspice library files - Hspice will use them directly (so will spectre, eldo, winspice, pspice and quite a few others).

I have done ASIC RF design to 5GHz using both Hspice and Spectre.  My comment would be: You do not need the "RF" versions; it is simply a matter of understanding the models, their parasitics and their coverage, correctly.  That said, if you do not understand (or feel that you dont understand) the models correctly, or do not have the mathematical skills and knowledge to apply the available models to "RF" problems, then it may be a good idea to pursuade your boss to spend the money on those "RF" tools to build confidence with the results of your simulations and of your design.  They are basically encapsulations of expertise, which you can apply.   In themselves they do not guarantee success, you still need to be able to critically decide if they are telling you the truth.

To help you decide if you can do your design in a common or garden variety of spice, or if you need a "bundled" solution, take a look at one of the resistor models in your PDK - do you know sufficient to be able to generate the schematics, bind the libraries then run the simulations in spectre, or write the scripts for Hspice to run a "Resistance vs Temp" simulation, or an input impedance plot to 10GHz or a CV curve for one of these resistors?

If so, then the answer is yes you can do RF simulation in either tool.

Just as an anecdote: I know of at least one person who has used Excel not only to do the circuit simulation, but a parameterised layout as well.  So the answer is probably that all of these tools simply solve the matrix you pose them.  The real skill is in how you pose the question in the first place.

Cheers,
           SimonH.