JFET level 1 (Shichman-Hodges)

Instance line: Jname …
Model line: .model mname njf | pjf, LEVEL=1
Terminals: Drain, Gate, Source
Described in: Junction field-effect transistors
Source: src/lib/dev/jfet/jfet.c

A JFET model without a LEVEL is level 1.

Instance parameters (26)

Input and output (6)

name	type	description	notes
`off`	flag	Device initially off	listed by show only when all parameters are asked for
`ic`	real vector	Initial VDS,VGS vector	ac; listed by show only when all parameters are asked for
`area`	real	Area factor	listed by show only when all parameters are asked for
`ic-vds`	real	Initial D-S voltage	ac; listed by show only when all parameters are asked for
`ic-vgs`	real	Initial G-S volrage	ac; listed by show only when all parameters are asked for
`temp`	real	Instance temperature	listed by show only when all parameters are asked for

Output only (20)

name	type	description	notes
`drain-node`	integer	Number of drain node	listed by show only when all parameters are asked for
`gate-node`	integer	Number of gate node	listed by show only when all parameters are asked for
`source-node`	integer	Number of source node	listed by show only when all parameters are asked for
`drain-prime-node`	integer	Internal drain node	listed by show only when all parameters are asked for
`source-prime-node`	integer	Internal source node	listed by show only when all parameters are asked for
`vgs`	real	Voltage G-S
`vgd`	real	Voltage G-D
`ig`	real	Current at gate node
`id`	real	Current at drain node
`is`	real	Source current
`igd`	real	Current G-D
`gm`	real	Transconductance
`gds`	real	Conductance D-S
`ggs`	real	Conductance G-S
`ggd`	real	Conductance G-D
`qgs`	real	Charge storage G-S junction	listed by show only when all parameters are asked for
`qgd`	real	Charge storage G-D junction	listed by show only when all parameters are asked for
`cqgs`	real	Capacitance due to charge storage G-S junction	listed by show only when all parameters are asked for
`cqgd`	real	Capacitance due to charge storage G-D junction	listed by show only when all parameters are asked for
`p`	real	Power dissipated by the JFET	listed by show only when all parameters are asked for

Model parameters (19)

Input and output (16)

name	type	description	notes
`njf`	flag	N type JFET model
`pjf`	flag	P type JFET model
`vt0` (also `vto`)	real	Threshold voltage
`beta`	real	Transconductance parameter
`lambda`	real	Channel length modulation param.
`rd`	real	Drain ohmic resistance
`rs`	real	Source ohmic resistance
`cgs`	real	G-S junction capactance	ac
`cgd`	real	G-D junction cap	ac
`pb`	real	Gate junction potential
`is`	real	Gate junction saturation current
`fc`	real	Forward bias junction fit parm.
`b`	real	Doping tail parameter
`tnom`	real	parameter measurement temperature	listed by show only when all parameters are asked for
`kf`	real	Flicker Noise Coefficient
`af`	real	Flicker Noise Exponent

Output only (3)

name	type	description	notes
`type`	string	N-type or P-type JFET model
`gd`	real	Drain conductance	listed by show only when all parameters are asked for
`gs`	real	Source conductance	listed by show only when all parameters are asked for

Parameters are set on the instance or .model line as keyword=value, and read back with @name[keyword] or the show and showmod commands. See the device reference.