Calculator Tab

A limited set of calculations is available with the calculator. Typically V/I for input resistance or V*I for power. For more complicated expressions, place a nonlinear function block on the schematic, and write a general equation, and then do a simulation. E.g.

B_a_source_name node_out1 node_out 2 v=V(net3, net4)*exp(net4)…

Group Delay

SuperSpice can calculate the group delay of a signal. This is Vg=d(phase)/dw

To plot group delay of a signal, set the calculator Function item to "GrpDel, d/dt" and enable the phase check box. Its a good idea to inhibit test points placed on the schematic or set them to phase only, to avoid a spurious magnitude signal being plotted as well on reruns.

It is also a good idea to run at least 100 points per decade in the AC sweep to obtain an accurate plot.

To have the calculation data automatically updated after each run, set the "Auto graph update calculation math data" check in the program options "PO" dialog. Disable this check when not examining group delay data in order to avoid extraneous graph windows.

Bugs

The is a bug in that sometimes the data axis shows deg instead of seconds. This can be ignored.

Zooming in can cause erroneous axis labels, e.g. all 0's. Ignore them and rely on the data readout

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