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Bipolar Junction Transistors (BJTs)

General Form:
qname nc nb ne [ns] modname [parameters ...]

Parameter Name Description
off Device is initially nonconducting, for circuit convergence assistance.
area=val Scale factor that multiplies all currents and other values, effectively modifying the BJT area.
ic=vbe,vce The initial voltages (initial condition) for transient analysis.
icvbe=vbe The initial vbe (initial condition) for transient analysis.
icvce=vce The initial vce (initial condition) for transient analysis.
temp=val Device operating temperature, degrees celsius.

Examples:
q23 10 24 13 qmod ic=0.6,5.0
q50a 11 26 4 20 mod1

The nc, nb, and ne are the collector, base, and emitter nodes, respectively, and ns is the (optional) substrate node. If unspecified, ground is used. The modname is the model name, area specifies the area factor, temp specifies the operating temperature, and off indicates an initial condition of the device for the dc analysis. If the area factor is omitted, a value of 1.0 is assumed. The initial conditions specified using ic or alternatively icvbe and icvce are intended for use with the uic option in transient analysis, when a transient analysis is desired starting from other than the quiescent operating point. The .ic line provides another way to set transient initial conditions.


next up previous contents index
Next: BJT Models (both NPN Up: Semiconductor Devices Previous: Diode Model   Contents   Index
Stephen R. Whiteley 2022-09-18