Soft Connect Terminal Functions

A softConnect terminal is a terminal that does not draw or carry any current.

A typical four terminal device has terminals for gate, drain, source, and the bulk node. The bulk node terminal is often not shown in a schematic representation. If the bulk node is shown, it is shown as connected to either power or ground. Similarly in a layout representation, the bulk node terminal is connected to either power or ground, but electrically it does not draw any current. Hence, it can be designated as a softConnect terminal.

Terminals are either explicit or implicit. Explicit terminals are explicitly created and managed by the user, whereas, implicit terminals are created and managed automatically by the database. An example of an implicit terminal would be one of the bit terminals associated with an explicit, multi-bit terminal.

Only explicit, single-bit terminals can be designated as softConnect terminals.

You can use the dbSetTermSoftConnect function to designate a terminal as a softConnect terminal.

After you designate a terminal as softConnect, you have the option to specify the following two attributes on the terminal:

pinlessTerminalLayer: when the softConnect terminal is not implemented by a shape, this layer is used to identify the area of the bulk node for the softConnect terminal.
connectToLayer: when the softConnect terminal is not implemented by a shape, this identifies the top level layer to which the corresponding instTerm will connect.

These attributes can be set independent of one another. When the softConnect terminal has an associated physical shape, the pinlessTerminalLayer and connectToLayer attributes are not needed.

It is an error to try to set either of these two attributes on a terminal that is not designated as softConnect.

This topic provides a list of Cadence® SKILL functions associated with soft connect terminals.

Only the functions listed here are supported for public use. All other functions, regardless of their name or prefix, and undocumented aspects of the functions described below, are private and are subject to change at anytime.

Virtuoso Studio Design Environment SKILL Reference
Product Version IC23.1, November 2023