Syntax Problem cir file

Q4 N007 N011 DGND 0 NP .2

Can I know the meaning of 0 NP .2 in the above syntax as NP indicates npn transistor what are the other two 0 and .2 indicates?

When all else fails, go to the originator. From “SPICE Circuit Components” at
(Part of " The SPICE User’s Guide ")

General form:
Q23 10 24 13 QMOD IC=0.6, 5.0
Q50A 11 26 4 20 MOD1
NC, NB, and NE are the collector, base, and emitter nodes, respectively. NS is the (optional) substrate node. If unspecified, ground is used. MNAME is the model name, AREA is the area factor, and OFF indicates an (optional) initial condition on the device for the dc analysis. If the area factor is omitted, a value of 1.0 is assumed. The (optional) initial condition specification using IC=VBE, VCE is intended for use with the UIC option on the .TRAN control line, when a transient analysis is desired starting from other than the quiescent operating point. See the .IC control line description for a better way to set transient initial conditions. The (optional) TEMP value is the temperature at which this device is to operate, and overrides the temperature specification on the .OPTION control line.

So it looks like this line refers to a transistor with a model name of " NP ", and a normalized area factor of " 0.2 ". The extra " 0 " before the model name is the nodename of the device’s substrate connection. In this case, the substrate is connected to the global " ground " node. The " 0 " and " .2 " parameters are used for specifying the transistors on an IC die, and don’t mean much when you are designing board-level circuits.


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