On Monday 25 November 2002 20:21, wolfgang buesser wrote: > 'Model=NMOS W=3.2um L=0.8um AD=6E-12 AS=6E-12' as > value > attribute. > Is there no posibility to enter this into separate > attributes with the chance to have default values?
And even better: Having calculated attributes. In IC design, specially analog, there are loads of transistors that may have different W/L relation. Many high-end simulators (like spectre) are pretty sensitive to some of the less obvious parameters like drain and source geometries. These numbers must either be calculated by hand and entered, or there are standard "shoot from the hip" values. After layout, there are backannotated transistor geometries available. It is for me more interesting to change the W and the L of a transistor, and have gnetlist calculate the rest so that my simulation is more accurate. Sometimes there is a lot of WL changement, and each time recalculate the other stuff is a hassle. Of course, IC design is a lot different than PCB design and there are other needs, but there is no reason why it should not be possible to replace cadence virtuoso composer for schematic capture. (It is stone age tech in a motif wrapping) -- Svenn Bjerkem
