How to Make a Million with LTspice

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Recently, an experienced (old) engineer (circuit designer) who does consulting jobs for a living told me, "Cadence would like you to believe that you can't design ICs without their expensive tools, but you can." Pspice is enough apparently. If you can architect and farm out blocks, that's really all you need. Of course, the user experience is crappy.. compared to Virtuoso.

XFAB supports Cadence and (maybe) Mentor/Tanner. But, what if you want to do the design (schematic) without investing in tools? Is there a way?

Sure - following the architect and farm model - you just need a way to import the LTspice databases into Cadence so you can do you full-chip LVS (layout vs schematic ver) in Cadence. Yes, you're still spending - but you might be able to get a Cadence license for a just a week and knock this out..

So, what do you need - one perl script that can take XFAB's hspice model deck and generate the design kit you can use with LTSpice. You need to push a button and out comes the symbols, subcircuit definitions and model files (minor syntax edits on the input model files) and a component-browser schematic that you can use as your palette and your in business. You will have to do some editing on the symbols to make them visually different - you do want a drain-extended MOS to look different from a regular MOS, etc.. So it's not totally automatic - but you can always get there if you want - just more work upfront.

And of course, you need some skill code that can generate the Cadence schematic database taking the LTspice db as input - if you look at LTspice - it's cool - just text files. Would be nice if they had a command interpreter log and a way to do custom bindkeys for macros - that would devastate Cadence..