Mxxxxxxx nd ng ns nb mname {args}
Mxxxxxxx nd ng ns nb mname
{width/length} {args}
.mosfet label nd ng ns nb mname {args}
.mosfet label nd ng ns nb mname
{width/length} {args}
.model mname NMOS {args} .model mname PMOS {args}
MOSFET.
Nd, ng, ns, and nb are the drain, gate, source, and bulk (substrate) nodes, respectively. Mname is the model name.
Length and width are the drawn channel length and width, in microns. Note that the notation W/L has units of microns, but the same parameters, in the argument list (W and L) have units of meters. All other dimensions are in meters.
The option (.options command) rstray determines whether or not series resistances are included. rstray (on) is the default. Experience has shown that the effect of series resistance is often not significant, it can significantly degrade the simulation time, and it often increases roundoff errors. rstray is the default for Spice compatibility, and because it usually is significant for the BJT model. Norstray (off) is the equivalent of setting the model parameters rd, rs, and rsh all to zero.
Entering a parameter value of 0 is not the same as not specifying it. This behavior is not compatible with SPICE. In SPICE, a value of 0 is often interpreted as not specified, with the result being to calculate it some other way. If you want it to be calculated, don’t specify it.
Another subtle difference from SPICE is that Gnucap may omit some unnecessary parts of the model, which may affect some reported values. It should not affect any voltages or currents. For example, if the gate and drain are tied, Cgs will be omitted from the model, so the printed value for Cgdovl and Cgd will be 0, which will disagree with SPICE. It doesn’t matter because a shorted capacitor can store no charge.
Levels 1, 2, 3, 4, 5, 6, 7, 8, 49 are implemented.
Gnucap supports “binning”. You can specify any number of models as a family. These models must have the selection parameters WMAX, WMIN, LMAX, and LMIN.
To use “binning”, define a set of models with the same name, except for a numeric extension, beginning at 1. The models must be numbered consecutively. For example, you might have a set of models: NM3U.1, NM3U.2, NM3U.3, NM3U.4, NM3U.5, NM3U.6. For the device, you would specify the model NM3U. The first model meeting the requirements that root
Gnucap behavioral modeling conditionals are an extension of the “AC” and “DC” Spice source parameters.
The extensions ...
The following are available:
A value or function with no conditional keyword is equivalent to ALL. For SPICE compatibility, use only DC, AC, or nothing.
They are interpreted like a “switch” statement. In case of a conflict, the last one applies. A set of precedence rules applies when some keys are missing. It is SPICE compatible to the extent the features overlap.
The following table describes the precedence rules:
width {IN=value} {OUT=value}
Set input and output width.
The ‘width’ command is the same as the ‘options’ command. It is provided for SPICE compatibility. SPICE uses width to set two parameters: in and out, which we set with the options command.
./usr/share/doc/gnucap/html/gnucap-man036.html 0000644 0000000 0000000 00000005131 11340024671 017755 0 ustar root rootmark
Remember circuit voltages and currents.
After the mark command, the transient and fourier analysis will continue from the values that were kept by the mark command, instead of progressing every time.
This allows reruns from the same starting point, which may be at any time, not necessarily 0.
./usr/share/doc/gnucap/html/gnucap-man075.html 0000644 0000000 0000000 00000074365 11340024671 017777 0 ustar root root
Mxxxxxxx nd ng ns nb mname {args}
Mxxxxxxx nd ng ns nb mname
{width/length} {args}
.mosfet label nd ng ns nb mname {args}
.mosfet label nd ng ns nb mname
{width/length} {args}
.model mname NMOS {args} .model mname PMOS {args}
MOSFET.
Nd, ng, ns, and nb are the drain, gate, source, and bulk (substrate) nodes, respectively. Mname is the model name.
Length and width are the drawn channel length and width, in microns. Note that the notation W/L has units of microns, but the same parameters, in the argument list (W and L) have units of meters. All other dimensions are in meters.
The option (.options command) rstray determines whether or not series resistances are included. rstray (on) is the default. Experience has shown that the effect of series resistance is often not significant, it can significantly degrade the simulation time, and it often increases roundoff errors. rstray is the default for Spice compatibility, and because it usually is significant for the BJT model. Norstray (off) is the equivalent of setting the model parameters rd, rs, and rsh all to zero.
Entering a parameter value of 0 is not the same as not specifying it. This behavior is not compatible with SPICE. In SPICE, a value of 0 is often interpreted as not specified, with the result being to calculate it some other way. If you want it to be calculated, don’t specify it.
Another subtle difference from SPICE is that Gnucap may omit some unnecessary parts of the model, which may affect some reported values. It should not affect any voltages or currents. For example, if the gate and drain are tied, Cgs will be omitted from the model, so the printed value for Cgdovl and Cgd will be 0, which will disagree with SPICE. It doesn’t matter because a shorted capacitor can store no charge.
Levels 1, 2, 3, 4, 5, 6, 7, 8, 49 are implemented.
Gnucap supports “binning”. You can specify any number of models as a family. These models must have the selection parameters WMAX, WMIN, LMAX, and LMIN.
To use “binning”, define a set of models with the same name, except for a numeric extension, beginning at 1. The models must be numbered consecutively. For example, you might have a set of models: NM3U.1, NM3U.2, NM3U.3, NM3U.4, NM3U.5, NM3U.6. For the device, you would specify the model NM3U. The first model meeting the requirements that root
Gnucap behavioral modeling conditionals are an extension of the “AC” and “DC” Spice source parameters.
The extensions ...
The following are available:
A value or function with no conditional keyword is equivalent to ALL. For SPICE compatibility, use only DC, AC, or nothing.
They are interpreted like a “switch” statement. In case of a conflict, the last one applies. A set of precedence rules applies when some keys are missing. It is SPICE compatible to the extent the features overlap.
The following table describes the precedence rules:
width {IN=value} {OUT=value}
Set input and output width.
The ‘width’ command is the same as the ‘options’ command. It is provided for SPICE compatibility. SPICE uses width to set two parameters: in and out, which we set with the options command.
./usr/share/doc/gnucap/html/gnucap-man036.html 0000644 0000000 0000000 00000005131 11340024671 017755 0 ustar root rootmark
Remember circuit voltages and currents.
After the mark command, the transient and fourier analysis will continue from the values that were kept by the mark command, instead of progressing every time.
This allows reruns from the same starting point, which may be at any time, not necessarily 0.