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Steven M Brown writes:

 > While kicking around the pseudo-layers, I did spot an inaccurate or
 > inconsistant pseudo-fet extraction (I have attached the file which
 > generated the inconsistancy). You will notice that the two resistive poly
 > lines are of the same width and length (or nearly so, depending on the
 > extraction of the poly contact). The pseudo-fet that was generated for
 > the ext_in poly line was of equal length, but wider than the feedback poly
 > line. Since the line was very long, this generates a large difference
 > between the two resistors. Hopefully, this is not an issue in 7.2.
 > 

hi Steve, you need to achive the same area/perimeter of the 'rpoly'
part of each resistor, if you want them to extract the same value,
since magic ultimately determines L/W by solving an equation using the
total area/perimeter it stores per node, so results vary from the
small area/perimeter differences of the 'rpoly' areas that you drew.

if you draw the same area, you get the same "L/W" values:

m1001 ext_in a_19_24 int_in Gnd polyResistor w=2 l=136
+ ad=0 pd=0 as=0 ps=0 
m1002 feedback a_19_13 int_in Gnd polyResistor w=2 l=136
+ ad=0 pd=0 as=0 ps=0 

this is less kludgey when you use 'silicide_block' layer to define the
resistor (which when available changes ohm/sq from like 5 to like
125), which has to be drawn explicitely 'distinct' due to spacing
rules anyway.

/jeff

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