SUBCKT Declarations in LTspice?

Question

Sent also directly to Helmut Sennewald...I have a whole chip design, relatively simple, simulates in 75 secondsin PSpice, that my customer would like made into a subcircuit forLTspice.Needless to say, this contains lots of CMOS, poly resistors andcapacitors, and PNP's; from X-FAB process XC-06.Will LTspice accept .MODEL statements within .SUBCKT declarations?If so, it should be a relatively simple netlist manipulation.Thanks!		                                        ...Jim Thompson-- | James E.Thompson, CTO                            |    mens     || Analog Innovations, Inc.                         |     et      || Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    || Phoenix, Arizona  85048    Skype: Contacts Only  |             || Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  || E-mail Icon at  |    1962     |             I love to cook with wine.     Sometimes I even put it in the food.

Joerg · Accepted Answer

Absolutamente will it. I do this all the time. Many RF transistor sims are done that way. You use a subcircuit to describe all the parasitic stuff of the package and then inside this subcircuit is the .MODEL for da trainsistah itself.

Jim Thompson · Answer

Great!  The customer will be happy, and I won't have to spend too much"support" time for a past project ;-)		                                        ...Jim Thompson-- | James E.Thompson, CTO                            |    mens     || Analog Innovations, Inc.                         |     et      || Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    || Phoenix, Arizona  85048    Skype: Contacts Only  |             || Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  || E-mail Icon at  |    1962     |               I can see November from my house :-)

Joerg · Answer

We are doing an IC for an X-Fab process right now. The client engineer said he ran a few chip things on LTSpice and to his surprise it crunched it without signs of indigestion.

Probably doesn't make Cadence too happy, because LTSpice is surprisingly compatible. Mathcad, different story, those guys seem to hang on to proprietary methods so one has to fork over big bux. I am going to have to now. Hurumph! ... grumble ...

Jim Thompson · Answer

Mike made LTspice pretty much PSpice conversant.If the GUI (particularly post-processing) was better I'd switch, butit's pretty lousy/unfriendly right now.		                                        ...Jim Thompson-- | James E.Thompson, CTO                            |    mens     || Analog Innovations, Inc.                         |     et      || Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    || Phoenix, Arizona  85048    Skype: Contacts Only  |             || Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  || E-mail Icon at  |    1962     |               I can see November from my house :-)

Fred Abse · Answer

Yes.LTSpice will usually digest PSpice lib files no problem.-- "For a successful technology, reality must take precedence over public relations, for nature cannot be fooled."                                       (Richard Feynman)

SUBCKT Declarations in LTspice?

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