Voltage-current diagram
What Is a Voltage-Current Diagram?
A voltage-current diagram, also known as a V-I diagram, plots electrical voltage and current in a common coordinate system. It shows how the two quantities relate to each other and which operating range a component, source, or test system covers.
This representation is particularly important for four-quadrant systems. Positive and negative values of voltage and current form four quadrants. In two quadrants, the system delivers electrical power and operates as a source; in the other two, it absorbs power and operates as a sink. Such operating ranges are relevant, for example, to products in the Source Measure Units (SMUs) category and products in the Bidirectional Power Supplies category.
A voltage-current diagram therefore shows which combinations of voltage, current, and power flow a device supports. However, it is not necessarily the same as an I-V characteristic. An I-V characteristic describes the functional relationship between current and voltage of a component or source.
A V-I diagram can also represent the permissible operating ranges of a measurement or test system.