SPICE G Element

HSPICE
Voltage dependent current source - G Element
Source: Synopsys HSPICE Simulation and Analysis User Guide V. W-2005.03, Mar. 2005

This section explains G Element syntax statements, and their parameters.
• Level=0 is a Voltage-Controlled Current Source (VCCS).
• Level=1 is a Voltage-Controlled Resistor (VCR).
• Level=2 is a Voltage-Controlled Capacitor (VCCAP), Negative Piece-Wise
Linear (NPWL).
• Level=3 is a VCCAP, Positive Piece-Wise Linear (PPWL).
See also “Using G and E Elements” in the HSPICE Applications Manual.

Voltage-Controlled Current Source (VCCS)
The Level=0 syntax is:
Linear
Gxxx n+ n- <VCCS> in+ in- transconductance <MAX=val>
+ <MIN=val> <SCALE=val> <M=val> <TC1=val> <TC2=val>
+ <ABS=1> <IC=val>
Polynomial (POLY)
Gxxx n+ n- <VCCS> POLY(NDIM) in1+ in1- ... <inndim+ inndim->
+ <MAX=val> <MIN=val> <SCALE=val> <M=val> <TC1=val>
+ <TC2=val> <ABS=1> P0<P1…> <IC=vals>
Piecewise Linear (PWL)
Gxxx n+ n- <VCCS> PWL(1) in+ in- <DELTA=val>
+ <SCALE=val> <M=val> <TC1=val> <TC2=val>
+ x1,y1 x2,y2 ... x100,y100 <IC=val> <SMOOTH=val>
Gxxx n+ n- <VCCS> NPWL(1) in+ in- <DELTA=val>
+ <SCALE=val> <M=val> <TC1=val><TC2=val>
+ x1,y1 x2,y2 ... x100,y100 <IC=val> <SMOOTH=val>
Gxxx n+ n- <VCCS> PPWL(1) in+ in- <DELTA=val>
+ <SCALE=val> <M=val> <TC1=val> <TC2=val>
+ x1,y1 x2,y2 ... x100,y100 <IC=val> <SMOOTH=val>
Multi-Input Gate
Gxxx n+ n- <VCCS> gatetype(k) in1+ in1- ...
+ ink+ ink- <DELTA=val> <TC1=val> <TC2=val> <SCALE=val>
+ <M=val> x1,y1 ... x100,y100<IC=val>
In this syntax, gatetype(k) can be AND, NAND, OR, or NOR gates.
Delay Element
Gxxx n+ n- <VCCS> DELAY in+ in- TD=val <SCALE=val>
+ <TC1=val> <TC2=val> NPDELAY=val


Laplace Transform
Syntax:
Transconductance H(s):
Gxxx n+ n- LAPLACE in+ in- k0, k1, ..., kn / d0,
+ d1, ..., dm
<SCALE=val> <TC1=val> <TC2=val> <M=val>
Voltage Gain H(s):
Exxx n+ n- LAPLACE in+ in- k0, k1, ..., kn / d0,
+ d1, ..., dm
<SCALE=val> <TC1=val> <TC2=val>
H(s) is a rational function, in the following form:
H(s)= (k0 + k1s + …+ knsn)/(d0 + d1s + … + dmsm)

You can use parameters to define the values of all coefficients (k0, k1, ..., d0,
d1, ...).


Example:
Glowpass 0 out LAPLACE in 0 1.0 / 1.0 2.0 2.0 1.0
Ehipass out 0 LAPLACE in 0 0.0,0.0,0.0,1.0 / 1.0,2.0,2.0,1.0
The Glowpass element statement describes a third-order low-pass filter, with
the transfer function:
H(s) = 1 / (1 + 2s + 2s2 + s3)

The Ehipass element statement describes a third-order high-pass filter, with
the transfer function:
H(s) = s3 / (1 + 2s + 2s2 + s3)