DVM: Managed Sources and Loads

DVM - Design Verification Module

Managed Sources and Loads

As described in Introduction to DVM, managed-source and managed-load symbols can represent any number of different electrical definitions, depending on the test objective of a particular simulation. While the source and load symbols do not visibly change, the electrical definition of the subcircuit called by the symbol does change.

For example, DVM can change the subcircuit used by a managed load symbol to do the following:

Represent a simple load resistor
Exhibit special transient behavior, such as change a pulsed load to simulate a load transient
Include an injected AC source and the Bode plot probe required for measurement in an AC Bode plot analysis

Likewise, a managed source subcircuit can do these things:

Represent a constant DC voltage source
Represent a start-up ramp or a pulsed line voltage source
Perform input impedance measurements by including components that inject an AC small signal perturbation into the circuit and measure the resulting input impedance

Configuring DVM Sources and Loads

You define which sources and loads are managed using the context menu Configure DVM Sources and Loads... on the DVM control symbol:

After selecting the sources and loads to manage, the reference designators (V2, I1 in this example) are saved to the DVM control symbol. You then need to edit the default specifications for the managed sources and loads. For more information, see the DVM Tutorial 3.1 Editing the Schematic topic.

Custom subcircuits can be designed as schematic components and then converted to ASCII models to be used with DVM.

Changing a Source or Load Subcircuit Definition

You change a source or load subcircuit definition using the Source and Load testplan entries.