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###

Voltage-Controlled Voltage Sources

This is a special case of the general source specification included
for backward compatibility.

- General Form:

`e`*name n*+ *n*- *nc*+ *nc*- [*expr*]
*srcargs*

e*name n*+ *n*- function | vol [`=`] *expr*
*srcargs*

e*name n*+ *n*- poly *poly_spec*
*srcargs*

where` `*srcargs* = [`ac table`(*name*)]

- Examples:

`e1 2 3 14 1 2.0
`

e2 2 3 14 1 x+.015*x*x

e3 2 3 function v(14,1)+.015*v(14,1)*v(14,1)

The *n*`+` is the positive node, and *n*`-` is the
negative node. *nc*`+` and *nc*`-` are the
positive and negative controlling nodes, respectively.

In the first form, if the *expr* is a constant, it represents the
linear voltage gain. If no expression is given, a unit constant
value is assumed. Otherwise, the *expr* computes the source
voltage, where the variable ```x`'' if used in the *expr* is
taken to be the controlling voltage (v(*nc*`+`,*nc*`-`)). In this case only, the `pwl` construct if used
in the *expr* takes as its input variable the value of ```x`'' rather than time, thus a piecewise linear transfer function can
be implemented using a `pwl` statement. The second form is
similar, but ```x`'' is not defined. The keywords ```function`'' and ```vol`'' are equivalent. The third form allows
use of the SPICE2 `poly` construct.

More information of the function specification can be found in
2.15, and the `poly` specification is described in
2.15.2.

If the `ac` parameter is given and the `table` keyword
follows, then the named table is taken to contain complex *transfer* coefficient data, which will be used in ac analysis (and
possibly elsewhere, see below). For each frequency, the source output
will be the interpolated transfer coefficient from the table
multiplied by the input. The table must be specified with a `.table` line, and must have the `ac` keyword given.

If an ac table is specified, and no dc/transient transfer function or
coefficient is given, then in transient analysis, the source transfer
will be obtained through Fourier analysis of the table data. This is
somewhat experimental, and may be prone to numerical errors.

In ac analysis, the transfer coefficient can be real or complex. If
complex, the imaginary value follows the real value. Only constants
or constant expressions are valid in this case. If the source
function is specified in this way, the real component is used in dc
and transient analysis. This will also override a table, if given.

** Next:** Current-Controlled Current Sources
** Up:** Dependent Sources
** Previous:** Voltage-Controlled Current Sources
** Contents**
** Index**
Stephen R. Whiteley
2017-03-28