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36 2. Tutorial
The Netlist command returns a raw netlist object which prints its content in short notation, i.e.
only the number of elements is shown. To get a more detailed view of the netlist content use the
command DisplayForm:
In[3]:= DisplayForm[voltageDivider]
Out[3]//DisplayForm= Netlist Raw, 3 Entries:
V0, 1, 0, 10
R1, 1, 2, R1
R2, 2, 0, R2
The netlist entry format (see Section 3.1.3) bears some remote similarity to that of the well-known and
widely used numerical circuit simulator SPICE in that circuit elements are specified by an individual
name, a list of nodes, and a value. In Analog Insydes, netlist entries must be lists of three fields
which are called the reference designator, the connectivity list, and the value field:
{reference designator, {connectivity list}, value field}
This global scheme describes the only valid syntax for netlist entries – there is no exception to this
format.
Reference Designators
The reference designator is a unique name by which a particular circuit element can be distinguished
from all other elements in the same netlist. Typically, the leading one, two, or three characters of a
reference designator implicitly determine the type of the corresponding element. Hence, V0 denotes
a voltage source (type tag V), R1 and R2 denote resistors (type tag R), and VCCS a voltage-controlled
current source (type tag VC).
There are mechanisms to override automatic type detection from reference designators explicitly but this and
other related advanced topics will be discussed later.
Unlike Mathematica variables, type tags are not case sensitive. Therefore, two circuit elements with
reference designators R1 and r1 are both recognized as resistors. However, the symbols R1 and r1
represent two entirely different elements.
Connectivity Lists and Node Identifiers
The connectivity list specifies the nodes of the circuit to which the terminals of an element are
connected. For that purpose, every node in a circuit must be given a unique name, a node identifier,
by which it can be referenced. While some circuit simulators require the nodes to be enumerated
by consecutive nonnegative integers, Analog Insydes lets you choose node identifiers quite freely.
You do not have to number your nodes consecutively, nor do you need to use numbers as node
identifiers at all. In addition to nonnegative integers, you may also use symbols or strings as node
labels. The only requirement is that the circuit’s ground node must be identified by the label 0
(zero). Internally all node identifiers are converted to strings. Thus, the node identifiers OUT and
"OUT" refer to the same node. Moreover, node identifiers are case sensitive. Thus, OUT and Out refer
to different nodes.