Ideal Switch (switch)

Ideal switch is a single-pole multiple-throw switch with infinite off resistance and zero on resistance. The switch is provided to allow you to reconfigure your circuit between analyses. You can only change the switch state between analyses (using the alter statement), not during an analysis.

When the switch is set to position 0 it is open. In other words, no terminal is connected to any other. When the switch is set to position 1, terminal 1 is connected to terminal 0, and all others are unconnected. When the position is set to 2, terminal 2 is connected to terminal 0, etc.

An offset voltage is supported. It is placed in series with the common terminal. The negative side of the source is connected to the common terminal.

The switch can change its position based on which analysis type is being performed using the xxx_position parameters. This feature should be used carefully. Careless use can generate discontinuities that result in convergence problems. Once an analysis specific position has been specified using xxx_position, it will always dominate over a position given with the position parameter. To disable an analysis specific position, alter it to its default value of unspecified.

This device is not supported within altergroup.

Sample Instance Statement

sw1 (t1 t2 t3) switch dc_position=0 ac_position=1 tran_position=2

Instance Syntax

Name  t0  t1 ... switch parameter=value ...

Instance Parameters

position=0	Switch position (0, 1, 2, ...).
dc_position	Position to which switch is set at start of DC analysis.
ac_position	Position to which switch is set at start of AC analysis.
tran_position	Position to which switch is set at start of transient analysis.
ic_position	Position to which switch is set at start of IC analysis (precedes transient analysis).
offset=0	Offset voltage in series with common terminal.
m=1.0	Multiplicity factor.

Output Parameters

present_position

Current switch position.

Related Topics

Ratiometric Fourier Analyzer (fourier)

IBIS I/O buffer (ibis_buffer)

Circuit Components

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