Pole Zero is a small-signal AC analysis which computes the poles and zeroes of a transfer function, where the inputs and the outputs are defined by the user.

A pole is any number that will cause the denominator in a transfer function equation to be zero. A zero is any number that will cause the numerator in a transfer function equation to be zero.

Both real and imaginary values are reported.

Sample files for use with analyses are installed at C:\Users\Public\Documents\National Instruments\Circuit Design Suite <version>\samples\Analyses\.

Analysis Parameters

The Analysis parameters tab contains the following:

  Parameter   Description
Analysis type Choose one of Gain analysis (output voltage/input voltage), Input impedance, Impedance analysis (output voltage/input current) or Output impedance.
Nodes

The input nodes are the positive and negative points in the circuit which are the transfer function inputs. Likewise, the output nodes are the positive and negative points in the circuit which are the transfer function outputs. You can use 0 (ground) for both positive nodes or both negative nodes.

Input (+)—Does not appear when Output impedance is selected.

Input (-)—Does not appear when Output impedance is selected.

Output (+)—Does not appear when Input impedance is selected.

Output (-)—Does not appear when Input impedance is selected.
Analyses performed

Pole-Zero Analysis—Reports all poles and zeros.

Pole Analysis—Reports all poles.

Zero Analysis—Reports all zeros.